bump gRPC to v1.3.0, add genproto, update protobuf

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

vendor.conf

@@ -18,7 +18,7 @@ github.com/docker/notary v0.4.2
 github.com/docker/swarmkit 79381d0840be27f8b3f5c667b348a4467d866eeb
 github.com/flynn-archive/go-shlex 3f9db97f856818214da2e1057f8ad84803971cff
 github.com/gogo/protobuf 7efa791bd276fd4db00867cbd982b552627c24cb
-github.com/golang/protobuf 8ee79997227bf9b34611aee7946ae64735e6fd93
+github.com/golang/protobuf 7a211bcf3bce0e3f1d74f9894916e6f116ae83b4
 github.com/gorilla/context v1.1
 github.com/gorilla/mux v1.1
 github.com/inconshreveable/mousetrap 76626ae9c91c4f2a10f34cad8ce83ea42c93bb75
@@ -44,7 +44,8 @@ golang.org/x/net c427ad74c6d7a814201695e9ffde0c5d400a7674
 golang.org/x/sys 8f0908ab3b2457e2e15403d3697c9ef5cb4b57a9
 golang.org/x/text f72d8390a633d5dfb0cc84043294db9f6c935756
 golang.org/x/time a4bde12657593d5e90d0533a3e4fd95e635124cb
-google.golang.org/grpc v1.0.4
+google.golang.org/genproto d80a6e20e776b0b17a324d0ba1ab50a39c8e8944
+google.golang.org/grpc v1.3.0
 gopkg.in/yaml.v2 4c78c975fe7c825c6d1466c42be594d1d6f3aba6
 github.com/tonistiigi/fsutil 0ac4c11b053b9c5c7c47558f81f96c7100ce50fb
 github.com/stevvooe/continuity cd7a8e21e2b6f84799f5dd4b65faf49c8d3ee02d

vendor/github.com/golang/protobuf/README.md

@@ -22,7 +22,7 @@ To use this software, you must:
   for details or, if you are using gccgo, follow the instructions at
 	https://golang.org/doc/install/gccgo
 - Grab the code from the repository and install the proto package.
-  The simplest way is to run `go get -u github.com/golang/protobuf/{proto,protoc-gen-go}`.
+  The simplest way is to run `go get -u github.com/golang/protobuf/protoc-gen-go`.
   The compiler plugin, protoc-gen-go, will be installed in $GOBIN,
   defaulting to $GOPATH/bin.  It must be in your $PATH for the protocol
   compiler, protoc, to find it.

vendor/github.com/golang/protobuf/ptypes/any/any.pb.go

@@ -0,0 +1,168 @@
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// source: github.com/golang/protobuf/ptypes/any/any.proto
+
+/*
+Package any is a generated protocol buffer package.
+
+It is generated from these files:
+	github.com/golang/protobuf/ptypes/any/any.proto
+
+It has these top-level messages:
+	Any
+*/
+package any
+
+import proto "github.com/golang/protobuf/proto"
+import fmt "fmt"
+import math "math"
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = fmt.Errorf
+var _ = math.Inf
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the proto package it is being compiled against.
+// A compilation error at this line likely means your copy of the
+// proto package needs to be updated.
+const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package
+
+// `Any` contains an arbitrary serialized protocol buffer message along with a
+// URL that describes the type of the serialized message.
+//
+// Protobuf library provides support to pack/unpack Any values in the form
+// of utility functions or additional generated methods of the Any type.
+//
+// Example 1: Pack and unpack a message in C++.
+//
+//     Foo foo = ...;
+//     Any any;
+//     any.PackFrom(foo);
+//     ...
+//     if (any.UnpackTo(&foo)) {
+//       ...
+//     }
+//
+// Example 2: Pack and unpack a message in Java.
+//
+//     Foo foo = ...;
+//     Any any = Any.pack(foo);
+//     ...
+//     if (any.is(Foo.class)) {
+//       foo = any.unpack(Foo.class);
+//     }
+//
+//  Example 3: Pack and unpack a message in Python.
+//
+//     foo = Foo(...)
+//     any = Any()
+//     any.Pack(foo)
+//     ...
+//     if any.Is(Foo.DESCRIPTOR):
+//       any.Unpack(foo)
+//       ...
+//
+// The pack methods provided by protobuf library will by default use
+// 'type.googleapis.com/full.type.name' as the type URL and the unpack
+// methods only use the fully qualified type name after the last '/'
+// in the type URL, for example "foo.bar.com/x/y.z" will yield type
+// name "y.z".
+//
+//
+// JSON
+// ====
+// The JSON representation of an `Any` value uses the regular
+// representation of the deserialized, embedded message, with an
+// additional field `@type` which contains the type URL. Example:
+//
+//     package google.profile;
+//     message Person {
+//       string first_name = 1;
+//       string last_name = 2;
+//     }
+//
+//     {
+//       "@type": "type.googleapis.com/google.profile.Person",
+//       "firstName": <string>,
+//       "lastName": <string>
+//     }
+//
+// If the embedded message type is well-known and has a custom JSON
+// representation, that representation will be embedded adding a field
+// `value` which holds the custom JSON in addition to the `@type`
+// field. Example (for message [google.protobuf.Duration][]):
+//
+//     {
+//       "@type": "type.googleapis.com/google.protobuf.Duration",
+//       "value": "1.212s"
+//     }
+//
+type Any struct {
+	// A URL/resource name whose content describes the type of the
+	// serialized protocol buffer message.
+	//
+	// For URLs which use the scheme `http`, `https`, or no scheme, the
+	// following restrictions and interpretations apply:
+	//
+	// * If no scheme is provided, `https` is assumed.
+	// * The last segment of the URL's path must represent the fully
+	//   qualified name of the type (as in `path/google.protobuf.Duration`).
+	//   The name should be in a canonical form (e.g., leading "." is
+	//   not accepted).
+	// * An HTTP GET on the URL must yield a [google.protobuf.Type][]
+	//   value in binary format, or produce an error.
+	// * Applications are allowed to cache lookup results based on the
+	//   URL, or have them precompiled into a binary to avoid any
+	//   lookup. Therefore, binary compatibility needs to be preserved
+	//   on changes to types. (Use versioned type names to manage
+	//   breaking changes.)
+	//
+	// Schemes other than `http`, `https` (or the empty scheme) might be
+	// used with implementation specific semantics.
+	//
+	TypeUrl string `protobuf:"bytes,1,opt,name=type_url,json=typeUrl" json:"type_url,omitempty"`
+	// Must be a valid serialized protocol buffer of the above specified type.
+	Value []byte `protobuf:"bytes,2,opt,name=value,proto3" json:"value,omitempty"`
+}
+
+func (m *Any) Reset()                    { *m = Any{} }
+func (m *Any) String() string            { return proto.CompactTextString(m) }
+func (*Any) ProtoMessage()               {}
+func (*Any) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{0} }
+func (*Any) XXX_WellKnownType() string   { return "Any" }
+
+func (m *Any) GetTypeUrl() string {
+	if m != nil {
+		return m.TypeUrl
+	}
+	return ""
+}
+
+func (m *Any) GetValue() []byte {
+	if m != nil {
+		return m.Value
+	}
+	return nil
+}
+
+func init() {
+	proto.RegisterType((*Any)(nil), "google.protobuf.Any")
+}
+
+func init() { proto.RegisterFile("github.com/golang/protobuf/ptypes/any/any.proto", fileDescriptor0) }
+
+var fileDescriptor0 = []byte{
+	// 184 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xe2, 0xd2, 0x4f, 0xcf, 0x2c, 0xc9,
+	0x28, 0x4d, 0xd2, 0x4b, 0xce, 0xcf, 0xd5, 0x4f, 0xcf, 0xcf, 0x49, 0xcc, 0x4b, 0xd7, 0x2f, 0x28,
+	0xca, 0x2f, 0xc9, 0x4f, 0x2a, 0x4d, 0xd3, 0x2f, 0x28, 0xa9, 0x2c, 0x48, 0x2d, 0xd6, 0x4f, 0xcc,
+	0xab, 0x04, 0x61, 0x3d, 0xb0, 0xb8, 0x10, 0x7f, 0x7a, 0x7e, 0x7e, 0x7a, 0x4e, 0xaa, 0x1e, 0x4c,
+	0x95, 0x92, 0x19, 0x17, 0xb3, 0x63, 0x5e, 0xa5, 0x90, 0x24, 0x17, 0x07, 0x48, 0x79, 0x7c, 0x69,
+	0x51, 0x8e, 0x04, 0xa3, 0x02, 0xa3, 0x06, 0x67, 0x10, 0x3b, 0x88, 0x1f, 0x5a, 0x94, 0x23, 0x24,
+	0xc2, 0xc5, 0x5a, 0x96, 0x98, 0x53, 0x9a, 0x2a, 0xc1, 0xa4, 0xc0, 0xa8, 0xc1, 0x13, 0x04, 0xe1,
+	0x38, 0xe5, 0x73, 0x09, 0x27, 0xe7, 0xe7, 0xea, 0xa1, 0x19, 0xe7, 0xc4, 0xe1, 0x98, 0x57, 0x19,
+	0x00, 0xe2, 0x04, 0x30, 0x46, 0xa9, 0x12, 0xe5, 0xb8, 0x45, 0x4c, 0xcc, 0xee, 0x01, 0x4e, 0xab,
+	0x98, 0xe4, 0xdc, 0x21, 0x46, 0x05, 0x40, 0x95, 0xe8, 0x85, 0xa7, 0xe6, 0xe4, 0x78, 0xe7, 0xe5,
+	0x97, 0xe7, 0x85, 0x80, 0x94, 0x26, 0xb1, 0x81, 0xf5, 0x1a, 0x03, 0x02, 0x00, 0x00, 0xff, 0xff,
+	0x45, 0x1f, 0x1a, 0xf2, 0xf3, 0x00, 0x00, 0x00,
+}

vendor/github.com/golang/protobuf/ptypes/any/any.proto

@@ -0,0 +1,139 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+syntax = "proto3";
+
+package google.protobuf;
+
+option csharp_namespace = "Google.Protobuf.WellKnownTypes";
+option go_package = "github.com/golang/protobuf/ptypes/any";
+option java_package = "com.google.protobuf";
+option java_outer_classname = "AnyProto";
+option java_multiple_files = true;
+option objc_class_prefix = "GPB";
+
+// `Any` contains an arbitrary serialized protocol buffer message along with a
+// URL that describes the type of the serialized message.
+//
+// Protobuf library provides support to pack/unpack Any values in the form
+// of utility functions or additional generated methods of the Any type.
+//
+// Example 1: Pack and unpack a message in C++.
+//
+//     Foo foo = ...;
+//     Any any;
+//     any.PackFrom(foo);
+//     ...
+//     if (any.UnpackTo(&foo)) {
+//       ...
+//     }
+//
+// Example 2: Pack and unpack a message in Java.
+//
+//     Foo foo = ...;
+//     Any any = Any.pack(foo);
+//     ...
+//     if (any.is(Foo.class)) {
+//       foo = any.unpack(Foo.class);
+//     }
+//
+//  Example 3: Pack and unpack a message in Python.
+//
+//     foo = Foo(...)
+//     any = Any()
+//     any.Pack(foo)
+//     ...
+//     if any.Is(Foo.DESCRIPTOR):
+//       any.Unpack(foo)
+//       ...
+//
+// The pack methods provided by protobuf library will by default use
+// 'type.googleapis.com/full.type.name' as the type URL and the unpack
+// methods only use the fully qualified type name after the last '/'
+// in the type URL, for example "foo.bar.com/x/y.z" will yield type
+// name "y.z".
+//
+//
+// JSON
+// ====
+// The JSON representation of an `Any` value uses the regular
+// representation of the deserialized, embedded message, with an
+// additional field `@type` which contains the type URL. Example:
+//
+//     package google.profile;
+//     message Person {
+//       string first_name = 1;
+//       string last_name = 2;
+//     }
+//
+//     {
+//       "@type": "type.googleapis.com/google.profile.Person",
+//       "firstName": <string>,
+//       "lastName": <string>
+//     }
+//
+// If the embedded message type is well-known and has a custom JSON
+// representation, that representation will be embedded adding a field
+// `value` which holds the custom JSON in addition to the `@type`
+// field. Example (for message [google.protobuf.Duration][]):
+//
+//     {
+//       "@type": "type.googleapis.com/google.protobuf.Duration",
+//       "value": "1.212s"
+//     }
+//
+message Any {
+  // A URL/resource name whose content describes the type of the
+  // serialized protocol buffer message.
+  //
+  // For URLs which use the scheme `http`, `https`, or no scheme, the
+  // following restrictions and interpretations apply:
+  //
+  // * If no scheme is provided, `https` is assumed.
+  // * The last segment of the URL's path must represent the fully
+  //   qualified name of the type (as in `path/google.protobuf.Duration`).
+  //   The name should be in a canonical form (e.g., leading "." is
+  //   not accepted).
+  // * An HTTP GET on the URL must yield a [google.protobuf.Type][]
+  //   value in binary format, or produce an error.
+  // * Applications are allowed to cache lookup results based on the
+  //   URL, or have them precompiled into a binary to avoid any
+  //   lookup. Therefore, binary compatibility needs to be preserved
+  //   on changes to types. (Use versioned type names to manage
+  //   breaking changes.)
+  //
+  // Schemes other than `http`, `https` (or the empty scheme) might be
+  // used with implementation specific semantics.
+  //
+  string type_url = 1;
+
+  // Must be a valid serialized protocol buffer of the above specified type.
+  bytes value = 2;
+}

vendor/google.golang.org/genproto/LICENSE

@@ -0,0 +1,202 @@
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
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+
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vendor/google.golang.org/genproto/README.md

@@ -0,0 +1,28 @@
+Go generated proto packages
+===========================
+
+[![Build Status](https://travis-ci.org/google/go-genproto.svg?branch=master)](https://travis-ci.org/google/go-genproto)
+[![GoDoc](https://godoc.org/google.golang.org/genproto?status.svg)](https://godoc.org/google.golang.org/genproto)
+
+> **IMPORTANT** This repository is currently experimental. The structure
+> of the contained packages is subject to change. Please see the original
+> source repositories (listed below) to find out the status of the each
+> protocol buffer's associated service.
+
+This repository contains the generated Go packages for common protocol buffer
+types, and the generated [gRPC][1] code necessary for interacting with Google's gRPC
+APIs.
+
+There are two sources for the proto files used in this repository:
+
+1. [google/protobuf][2]: the code in the `protobuf` and `ptypes` subdirectories
+   is derived from this repo. The messages in `protobuf` are used to describe
+   protocol buffer messages themselves. The messages under `ptypes` define the
+   common well-known types.
+2. [googleapis/googleapis][3]: the code in the `googleapis` is derived from this
+   repo. The packages here contain types specifically for interacting with Google
+   APIs.
+
+[1]: http://grpc.io
+[2]: https://github.com/google/protobuf/
+[3]: https://github.com/googleapis/googleapis/

vendor/google.golang.org/genproto/googleapis/rpc/status/status.pb.go

@@ -0,0 +1,144 @@
+// Code generated by protoc-gen-go.
+// source: google/rpc/status.proto
+// DO NOT EDIT!
+
+/*
+Package status is a generated protocol buffer package.
+
+It is generated from these files:
+	google/rpc/status.proto
+
+It has these top-level messages:
+	Status
+*/
+package status
+
+import proto "github.com/golang/protobuf/proto"
+import fmt "fmt"
+import math "math"
+import google_protobuf "github.com/golang/protobuf/ptypes/any"
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = fmt.Errorf
+var _ = math.Inf
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the proto package it is being compiled against.
+// A compilation error at this line likely means your copy of the
+// proto package needs to be updated.
+const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package
+
+// The `Status` type defines a logical error model that is suitable for different
+// programming environments, including REST APIs and RPC APIs. It is used by
+// [gRPC](https://github.com/grpc). The error model is designed to be:
+//
+// - Simple to use and understand for most users
+// - Flexible enough to meet unexpected needs
+//
+// # Overview
+//
+// The `Status` message contains three pieces of data: error code, error message,
+// and error details. The error code should be an enum value of
+// [google.rpc.Code][google.rpc.Code], but it may accept additional error codes if needed.  The
+// error message should be a developer-facing English message that helps
+// developers *understand* and *resolve* the error. If a localized user-facing
+// error message is needed, put the localized message in the error details or
+// localize it in the client. The optional error details may contain arbitrary
+// information about the error. There is a predefined set of error detail types
+// in the package `google.rpc` which can be used for common error conditions.
+//
+// # Language mapping
+//
+// The `Status` message is the logical representation of the error model, but it
+// is not necessarily the actual wire format. When the `Status` message is
+// exposed in different client libraries and different wire protocols, it can be
+// mapped differently. For example, it will likely be mapped to some exceptions
+// in Java, but more likely mapped to some error codes in C.
+//
+// # Other uses
+//
+// The error model and the `Status` message can be used in a variety of
+// environments, either with or without APIs, to provide a
+// consistent developer experience across different environments.
+//
+// Example uses of this error model include:
+//
+// - Partial errors. If a service needs to return partial errors to the client,
+//     it may embed the `Status` in the normal response to indicate the partial
+//     errors.
+//
+// - Workflow errors. A typical workflow has multiple steps. Each step may
+//     have a `Status` message for error reporting purpose.
+//
+// - Batch operations. If a client uses batch request and batch response, the
+//     `Status` message should be used directly inside batch response, one for
+//     each error sub-response.
+//
+// - Asynchronous operations. If an API call embeds asynchronous operation
+//     results in its response, the status of those operations should be
+//     represented directly using the `Status` message.
+//
+// - Logging. If some API errors are stored in logs, the message `Status` could
+//     be used directly after any stripping needed for security/privacy reasons.
+type Status struct {
+	// The status code, which should be an enum value of [google.rpc.Code][google.rpc.Code].
+	Code int32 `protobuf:"varint,1,opt,name=code" json:"code,omitempty"`
+	// A developer-facing error message, which should be in English. Any
+	// user-facing error message should be localized and sent in the
+	// [google.rpc.Status.details][google.rpc.Status.details] field, or localized by the client.
+	Message string `protobuf:"bytes,2,opt,name=message" json:"message,omitempty"`
+	// A list of messages that carry the error details.  There will be a
+	// common set of message types for APIs to use.
+	Details []*google_protobuf.Any `protobuf:"bytes,3,rep,name=details" json:"details,omitempty"`
+}
+
+func (m *Status) Reset()                    { *m = Status{} }
+func (m *Status) String() string            { return proto.CompactTextString(m) }
+func (*Status) ProtoMessage()               {}
+func (*Status) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{0} }
+
+func (m *Status) GetCode() int32 {
+	if m != nil {
+		return m.Code
+	}
+	return 0
+}
+
+func (m *Status) GetMessage() string {
+	if m != nil {
+		return m.Message
+	}
+	return ""
+}
+
+func (m *Status) GetDetails() []*google_protobuf.Any {
+	if m != nil {
+		return m.Details
+	}
+	return nil
+}
+
+func init() {
+	proto.RegisterType((*Status)(nil), "google.rpc.Status")
+}
+
+func init() { proto.RegisterFile("google/rpc/status.proto", fileDescriptor0) }
+
+var fileDescriptor0 = []byte{
+	// 209 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xe2, 0x12, 0x4f, 0xcf, 0xcf, 0x4f,
+	0xcf, 0x49, 0xd5, 0x2f, 0x2a, 0x48, 0xd6, 0x2f, 0x2e, 0x49, 0x2c, 0x29, 0x2d, 0xd6, 0x2b, 0x28,
+	0xca, 0x2f, 0xc9, 0x17, 0xe2, 0x82, 0x48, 0xe8, 0x15, 0x15, 0x24, 0x4b, 0x49, 0x42, 0x15, 0x81,
+	0x65, 0x92, 0x4a, 0xd3, 0xf4, 0x13, 0xf3, 0x2a, 0x21, 0xca, 0x94, 0xd2, 0xb8, 0xd8, 0x82, 0xc1,
+	0xda, 0x84, 0x84, 0xb8, 0x58, 0x92, 0xf3, 0x53, 0x52, 0x25, 0x18, 0x15, 0x18, 0x35, 0x58, 0x83,
+	0xc0, 0x6c, 0x21, 0x09, 0x2e, 0xf6, 0xdc, 0xd4, 0xe2, 0xe2, 0xc4, 0xf4, 0x54, 0x09, 0x26, 0x05,
+	0x46, 0x0d, 0xce, 0x20, 0x18, 0x57, 0x48, 0x8f, 0x8b, 0x3d, 0x25, 0xb5, 0x24, 0x31, 0x33, 0xa7,
+	0x58, 0x82, 0x59, 0x81, 0x59, 0x83, 0xdb, 0x48, 0x44, 0x0f, 0x6a, 0x21, 0xcc, 0x12, 0x3d, 0xc7,
+	0xbc, 0xca, 0x20, 0x98, 0x22, 0xa7, 0x38, 0x2e, 0xbe, 0xe4, 0xfc, 0x5c, 0x3d, 0x84, 0xa3, 0x9c,
+	0xb8, 0x21, 0xf6, 0x06, 0x80, 0x94, 0x07, 0x30, 0x46, 0x99, 0x43, 0xa5, 0xd2, 0xf3, 0x73, 0x12,
+	0xf3, 0xd2, 0xf5, 0xf2, 0x8b, 0xd2, 0xf5, 0xd3, 0x53, 0xf3, 0xc0, 0x86, 0xe9, 0x43, 0xa4, 0x12,
+	0x0b, 0x32, 0x8b, 0x91, 0xfc, 0x69, 0x0d, 0xa1, 0x16, 0x31, 0x31, 0x07, 0x05, 0x38, 0x27, 0xb1,
+	0x81, 0x55, 0x1a, 0x03, 0x02, 0x00, 0x00, 0xff, 0xff, 0xa4, 0x53, 0xf0, 0x7c, 0x10, 0x01, 0x00,
+	0x00,
+}

vendor/google.golang.org/grpc/README.md

@@ -1,4 +1,4 @@
-#gRPC-Go
+# gRPC-Go
 
 [![Build Status](https://travis-ci.org/grpc/grpc-go.svg)](https://travis-ci.org/grpc/grpc-go) [![GoDoc](https://godoc.org/google.golang.org/grpc?status.svg)](https://godoc.org/google.golang.org/grpc)
 
@@ -16,7 +16,7 @@ $ go get google.golang.org/grpc
 Prerequisites
 -------------
 
-This requires Go 1.5 or later.
+This requires Go 1.6 or later.
 
 Constraints
 -----------
@@ -30,3 +30,12 @@ Status
 ------
 GA
 
+FAQ
+---
+
+#### Compiling error, undefined: grpc.SupportPackageIsVersion
+
+Please update proto package, gRPC package and rebuild the proto files:
+ - `go get -u github.com/golang/protobuf/{proto,protoc-gen-go}`
+ - `go get -u google.golang.org/grpc`
+ - `protoc --go_out=plugins=grpc:. *.proto`

vendor/google.golang.org/grpc/call.go

@@ -36,12 +36,14 @@ package grpc
 import (
 	"bytes"
 	"io"
-	"math"
 	"time"
 
 	"golang.org/x/net/context"
 	"golang.org/x/net/trace"
 	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/peer"
+	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
 	"google.golang.org/grpc/transport"
 )
 
@@ -49,7 +51,8 @@ import (
 // On error, it returns the error and indicates whether the call should be retried.
 //
 // TODO(zhaoq): Check whether the received message sequence is valid.
-func recvResponse(dopts dialOptions, t transport.ClientTransport, c *callInfo, stream *transport.Stream, reply interface{}) (err error) {
+// TODO ctx is used for stats collection and processing. It is the context passed from the application.
+func recvResponse(ctx context.Context, dopts dialOptions, t transport.ClientTransport, c *callInfo, stream *transport.Stream, reply interface{}) (err error) {
 	// Try to acquire header metadata from the server if there is any.
 	defer func() {
 		if err != nil {
@@ -63,24 +66,34 @@ func recvResponse(dopts dialOptions, t transport.ClientTransport, c *callInfo, s
 		return
 	}
 	p := &parser{r: stream}
+	var inPayload *stats.InPayload
+	if dopts.copts.StatsHandler != nil {
+		inPayload = &stats.InPayload{
+			Client: true,
+		}
+	}
 	for {
-		if err = recv(p, dopts.codec, stream, dopts.dc, reply, math.MaxInt32); err != nil {
+		if err = recv(p, dopts.codec, stream, dopts.dc, reply, dopts.maxMsgSize, inPayload); err != nil {
 			if err == io.EOF {
 				break
 			}
 			return
 		}
 	}
+	if inPayload != nil && err == io.EOF && stream.Status().Code() == codes.OK {
+		// TODO in the current implementation, inTrailer may be handled before inPayload in some cases.
+		// Fix the order if necessary.
+		dopts.copts.StatsHandler.HandleRPC(ctx, inPayload)
+	}
 	c.trailerMD = stream.Trailer()
+	if peer, ok := peer.FromContext(stream.Context()); ok {
+		c.peer = peer
+	}
 	return nil
 }
 
 // sendRequest writes out various information of an RPC such as Context and Message.
-func sendRequest(ctx context.Context, codec Codec, compressor Compressor, callHdr *transport.CallHdr, t transport.ClientTransport, args interface{}, opts *transport.Options) (_ *transport.Stream, err error) {
+func sendRequest(ctx context.Context, dopts dialOptions, compressor Compressor, callHdr *transport.CallHdr, stream *transport.Stream, t transport.ClientTransport, args interface{}, opts *transport.Options) (err error) {
-	stream, err := t.NewStream(ctx, callHdr)
-	if err != nil {
-		return nil, err
-	}
 	defer func() {
 		if err != nil {
 			// If err is connection error, t will be closed, no need to close stream here.
@@ -89,23 +102,35 @@ func sendRequest(ctx context.Context, codec Codec, compressor Compressor, callHd
 			}
 		}
 	}()
-	var cbuf *bytes.Buffer
+	var (
+		cbuf       *bytes.Buffer
+		outPayload *stats.OutPayload
+	)
 	if compressor != nil {
 		cbuf = new(bytes.Buffer)
 	}
-	outBuf, err := encode(codec, args, compressor, cbuf)
+	if dopts.copts.StatsHandler != nil {
+		outPayload = &stats.OutPayload{
+			Client: true,
+		}
+	}
+	outBuf, err := encode(dopts.codec, args, compressor, cbuf, outPayload)
 	if err != nil {
-		return nil, Errorf(codes.Internal, "grpc: %v", err)
+		return Errorf(codes.Internal, "grpc: %v", err)
 	}
 	err = t.Write(stream, outBuf, opts)
+	if err == nil && outPayload != nil {
+		outPayload.SentTime = time.Now()
+		dopts.copts.StatsHandler.HandleRPC(ctx, outPayload)
+	}
 	// t.NewStream(...) could lead to an early rejection of the RPC (e.g., the service/method
 	// does not exist.) so that t.Write could get io.EOF from wait(...). Leave the following
 	// recvResponse to get the final status.
 	if err != nil && err != io.EOF {
-		return nil, err
+		return err
 	}
 	// Sent successfully.
-	return stream, nil
+	return nil
 }
 
 // Invoke sends the RPC request on the wire and returns after response is received.
@@ -118,8 +143,16 @@ func Invoke(ctx context.Context, method string, args, reply interface{}, cc *Cli
 	return invoke(ctx, method, args, reply, cc, opts...)
 }
 
-func invoke(ctx context.Context, method string, args, reply interface{}, cc *ClientConn, opts ...CallOption) (err error) {
+func invoke(ctx context.Context, method string, args, reply interface{}, cc *ClientConn, opts ...CallOption) (e error) {
 	c := defaultCallInfo
+	if mc, ok := cc.getMethodConfig(method); ok {
+		c.failFast = !mc.WaitForReady
+		if mc.Timeout > 0 {
+			var cancel context.CancelFunc
+			ctx, cancel = context.WithTimeout(ctx, mc.Timeout)
+			defer cancel()
+		}
+	}
 	for _, o := range opts {
 		if err := o.before(&c); err != nil {
 			return toRPCErr(err)
@@ -140,12 +173,33 @@ func invoke(ctx context.Context, method string, args, reply interface{}, cc *Cli
 		c.traceInfo.tr.LazyLog(&c.traceInfo.firstLine, false)
 		// TODO(dsymonds): Arrange for c.traceInfo.firstLine.remoteAddr to be set.
 		defer func() {
-			if err != nil {
+			if e != nil {
-				c.traceInfo.tr.LazyLog(&fmtStringer{"%v", []interface{}{err}}, true)
+				c.traceInfo.tr.LazyLog(&fmtStringer{"%v", []interface{}{e}}, true)
 				c.traceInfo.tr.SetError()
 			}
 		}()
 	}
+	ctx = newContextWithRPCInfo(ctx)
+	sh := cc.dopts.copts.StatsHandler
+	if sh != nil {
+		ctx = sh.TagRPC(ctx, &stats.RPCTagInfo{FullMethodName: method})
+		begin := &stats.Begin{
+			Client:    true,
+			BeginTime: time.Now(),
+			FailFast:  c.failFast,
+		}
+		sh.HandleRPC(ctx, begin)
+	}
+	defer func() {
+		if sh != nil {
+			end := &stats.End{
+				Client:  true,
+				EndTime: time.Now(),
+				Error:   e,
+			}
+			sh.HandleRPC(ctx, end)
+		}
+	}()
 	topts := &transport.Options{
 		Last:  true,
 		Delay: false,
@@ -167,13 +221,14 @@ func invoke(ctx context.Context, method string, args, reply interface{}, cc *Cli
 		if cc.dopts.cp != nil {
 			callHdr.SendCompress = cc.dopts.cp.Type()
 		}
+
 		gopts := BalancerGetOptions{
 			BlockingWait: !c.failFast,
 		}
 		t, put, err = cc.getTransport(ctx, gopts)
 		if err != nil {
 			// TODO(zhaoq): Probably revisit the error handling.
-			if _, ok := err.(*rpcError); ok {
+			if _, ok := status.FromError(err); ok {
 				return err
 			}
 			if err == errConnClosing || err == errConnUnavailable {
@@ -188,33 +243,49 @@ func invoke(ctx context.Context, method string, args, reply interface{}, cc *Cli
 		if c.traceInfo.tr != nil {
 			c.traceInfo.tr.LazyLog(&payload{sent: true, msg: args}, true)
 		}
-		stream, err = sendRequest(ctx, cc.dopts.codec, cc.dopts.cp, callHdr, t, args, topts)
+		stream, err = t.NewStream(ctx, callHdr)
 		if err != nil {
 			if put != nil {
+				if _, ok := err.(transport.ConnectionError); ok {
+					// If error is connection error, transport was sending data on wire,
+					// and we are not sure if anything has been sent on wire.
+					// If error is not connection error, we are sure nothing has been sent.
+					updateRPCInfoInContext(ctx, rpcInfo{bytesSent: true, bytesReceived: false})
+				}
 				put()
-				put = nil
-			}
-			// Retry a non-failfast RPC when
-			// i) there is a connection error; or
-			// ii) the server started to drain before this RPC was initiated.
-			if _, ok := err.(transport.ConnectionError); ok || err == transport.ErrStreamDrain {
-				if c.failFast {
-					return toRPCErr(err)
 			}
+			if _, ok := err.(transport.ConnectionError); (ok || err == transport.ErrStreamDrain) && !c.failFast {
 				continue
 			}
 			return toRPCErr(err)
 		}
-		err = recvResponse(cc.dopts, t, &c, stream, reply)
+		err = sendRequest(ctx, cc.dopts, cc.dopts.cp, callHdr, stream, t, args, topts)
 		if err != nil {
 			if put != nil {
+				updateRPCInfoInContext(ctx, rpcInfo{
+					bytesSent:     stream.BytesSent(),
+					bytesReceived: stream.BytesReceived(),
+				})
 				put()
-				put = nil
 			}
-			if _, ok := err.(transport.ConnectionError); ok || err == transport.ErrStreamDrain {
+			// Retry a non-failfast RPC when
-				if c.failFast {
+			// i) there is a connection error; or
+			// ii) the server started to drain before this RPC was initiated.
+			if _, ok := err.(transport.ConnectionError); (ok || err == transport.ErrStreamDrain) && !c.failFast {
+				continue
+			}
 			return toRPCErr(err)
 		}
+		err = recvResponse(ctx, cc.dopts, t, &c, stream, reply)
+		if err != nil {
+			if put != nil {
+				updateRPCInfoInContext(ctx, rpcInfo{
+					bytesSent:     stream.BytesSent(),
+					bytesReceived: stream.BytesReceived(),
+				})
+				put()
+			}
+			if _, ok := err.(transport.ConnectionError); (ok || err == transport.ErrStreamDrain) && !c.failFast {
 				continue
 			}
 			return toRPCErr(err)
@@ -224,9 +295,12 @@ func invoke(ctx context.Context, method string, args, reply interface{}, cc *Cli
 		}
 		t.CloseStream(stream, nil)
 		if put != nil {
+			updateRPCInfoInContext(ctx, rpcInfo{
+				bytesSent:     stream.BytesSent(),
+				bytesReceived: stream.BytesReceived(),
+			})
 			put()
-			put = nil
 		}
-		return Errorf(stream.StatusCode(), "%s", stream.StatusDesc())
+		return stream.Status().Err()
 	}
 }

vendor/google.golang.org/grpc/clientconn.go

@@ -36,8 +36,8 @@ package grpc
 import (
 	"errors"
 	"fmt"
+	"math"
 	"net"
-	"strings"
 	"sync"
 	"time"
 
@@ -45,6 +45,8 @@ import (
 	"golang.org/x/net/trace"
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/keepalive"
+	"google.golang.org/grpc/stats"
 	"google.golang.org/grpc/transport"
 )
 
@@ -54,6 +56,8 @@ var (
 	ErrClientConnClosing = errors.New("grpc: the client connection is closing")
 	// ErrClientConnTimeout indicates that the ClientConn cannot establish the
 	// underlying connections within the specified timeout.
+	// DEPRECATED: Please use context.DeadlineExceeded instead. This error will be
+	// removed in Q1 2017.
 	ErrClientConnTimeout = errors.New("grpc: timed out when dialing")
 
 	// errNoTransportSecurity indicates that there is no transport security
@@ -75,7 +79,6 @@ var (
 	errConnClosing = errors.New("grpc: the connection is closing")
 	// errConnUnavailable indicates that the connection is unavailable.
 	errConnUnavailable = errors.New("grpc: the connection is unavailable")
-	errNoAddr          = errors.New("grpc: there is no address available to dial")
 	// minimum time to give a connection to complete
 	minConnectTimeout = 20 * time.Second
 )
@@ -93,12 +96,23 @@ type dialOptions struct {
 	block      bool
 	insecure   bool
 	timeout    time.Duration
+	scChan     <-chan ServiceConfig
 	copts      transport.ConnectOptions
+	maxMsgSize int
 }
 
+const defaultClientMaxMsgSize = math.MaxInt32
+
 // DialOption configures how we set up the connection.
 type DialOption func(*dialOptions)
 
+// WithMaxMsgSize returns a DialOption which sets the maximum message size the client can receive.
+func WithMaxMsgSize(s int) DialOption {
+	return func(o *dialOptions) {
+		o.maxMsgSize = s
+	}
+}
+
 // WithCodec returns a DialOption which sets a codec for message marshaling and unmarshaling.
 func WithCodec(c Codec) DialOption {
 	return func(o *dialOptions) {
@@ -129,6 +143,13 @@ func WithBalancer(b Balancer) DialOption {
 	}
 }
 
+// WithServiceConfig returns a DialOption which has a channel to read the service configuration.
+func WithServiceConfig(c <-chan ServiceConfig) DialOption {
+	return func(o *dialOptions) {
+		o.scChan = c
+	}
+}
+
 // WithBackoffMaxDelay configures the dialer to use the provided maximum delay
 // when backing off after failed connection attempts.
 func WithBackoffMaxDelay(md time.Duration) DialOption {
@@ -199,6 +220,8 @@ func WithTimeout(d time.Duration) DialOption {
 }
 
 // WithDialer returns a DialOption that specifies a function to use for dialing network addresses.
+// If FailOnNonTempDialError() is set to true, and an error is returned by f, gRPC checks the error's
+// Temporary() method to decide if it should try to reconnect to the network address.
 func WithDialer(f func(string, time.Duration) (net.Conn, error)) DialOption {
 	return func(o *dialOptions) {
 		o.copts.Dialer = func(ctx context.Context, addr string) (net.Conn, error) {
@@ -210,6 +233,25 @@ func WithDialer(f func(string, time.Duration) (net.Conn, error)) DialOption {
 	}
 }
 
+// WithStatsHandler returns a DialOption that specifies the stats handler
+// for all the RPCs and underlying network connections in this ClientConn.
+func WithStatsHandler(h stats.Handler) DialOption {
+	return func(o *dialOptions) {
+		o.copts.StatsHandler = h
+	}
+}
+
+// FailOnNonTempDialError returns a DialOption that specified if gRPC fails on non-temporary dial errors.
+// If f is true, and dialer returns a non-temporary error, gRPC will fail the connection to the network
+// address and won't try to reconnect.
+// The default value of FailOnNonTempDialError is false.
+// This is an EXPERIMENTAL API.
+func FailOnNonTempDialError(f bool) DialOption {
+	return func(o *dialOptions) {
+		o.copts.FailOnNonTempDialError = f
+	}
+}
+
 // WithUserAgent returns a DialOption that specifies a user agent string for all the RPCs.
 func WithUserAgent(s string) DialOption {
 	return func(o *dialOptions) {
@@ -217,6 +259,13 @@ func WithUserAgent(s string) DialOption {
 	}
 }
 
+// WithKeepaliveParams returns a DialOption that specifies keepalive paramaters for the client transport.
+func WithKeepaliveParams(kp keepalive.ClientParameters) DialOption {
+	return func(o *dialOptions) {
+		o.copts.KeepaliveParams = kp
+	}
+}
+
 // WithUnaryInterceptor returns a DialOption that specifies the interceptor for unary RPCs.
 func WithUnaryInterceptor(f UnaryClientInterceptor) DialOption {
 	return func(o *dialOptions) {
@@ -231,6 +280,15 @@ func WithStreamInterceptor(f StreamClientInterceptor) DialOption {
 	}
 }
 
+// WithAuthority returns a DialOption that specifies the value to be used as
+// the :authority pseudo-header. This value only works with WithInsecure and
+// has no effect if TransportCredentials are present.
+func WithAuthority(a string) DialOption {
+	return func(o *dialOptions) {
+		o.copts.Authority = a
+	}
+}
+
 // Dial creates a client connection to the given target.
 func Dial(target string, opts ...DialOption) (*ClientConn, error) {
 	return DialContext(context.Background(), target, opts...)
@@ -247,6 +305,32 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 		conns:  make(map[Address]*addrConn),
 	}
 	cc.ctx, cc.cancel = context.WithCancel(context.Background())
+	cc.dopts.maxMsgSize = defaultClientMaxMsgSize
+	for _, opt := range opts {
+		opt(&cc.dopts)
+	}
+	cc.mkp = cc.dopts.copts.KeepaliveParams
+
+	if cc.dopts.copts.Dialer == nil {
+		cc.dopts.copts.Dialer = newProxyDialer(
+			func(ctx context.Context, addr string) (net.Conn, error) {
+				return dialContext(ctx, "tcp", addr)
+			},
+		)
+	}
+
+	if cc.dopts.copts.UserAgent != "" {
+		cc.dopts.copts.UserAgent += " " + grpcUA
+	} else {
+		cc.dopts.copts.UserAgent = grpcUA
+	}
+
+	if cc.dopts.timeout > 0 {
+		var cancel context.CancelFunc
+		ctx, cancel = context.WithTimeout(ctx, cc.dopts.timeout)
+		defer cancel()
+	}
+
 	defer func() {
 		select {
 		case <-ctx.Done():
@@ -259,10 +343,17 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 		}
 	}()
 
-	for _, opt := range opts {
+	if cc.dopts.scChan != nil {
-		opt(&cc.dopts)
+		// Wait for the initial service config.
+		select {
+		case sc, ok := <-cc.dopts.scChan:
+			if ok {
+				cc.sc = sc
+			}
+		case <-ctx.Done():
+			return nil, ctx.Err()
+		}
 	}
-
 	// Set defaults.
 	if cc.dopts.codec == nil {
 		cc.dopts.codec = protoCodec{}
@@ -273,21 +364,18 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 	creds := cc.dopts.copts.TransportCredentials
 	if creds != nil && creds.Info().ServerName != "" {
 		cc.authority = creds.Info().ServerName
+	} else if cc.dopts.insecure && cc.dopts.copts.Authority != "" {
+		cc.authority = cc.dopts.copts.Authority
 	} else {
-		colonPos := strings.LastIndex(target, ":")
+		cc.authority = target
-		if colonPos == -1 {
-			colonPos = len(target)
 	}
-		cc.authority = target[:colonPos]
-	}
-	var ok bool
 	waitC := make(chan error, 1)
 	go func() {
-		var addrs []Address
+		defer close(waitC)
-		if cc.dopts.balancer == nil {
+		if cc.dopts.balancer == nil && cc.sc.LB != nil {
-			// Connect to target directly if balancer is nil.
+			cc.dopts.balancer = cc.sc.LB
-			addrs = append(addrs, Address{Addr: target})
+		}
-		} else {
+		if cc.dopts.balancer != nil {
 			var credsClone credentials.TransportCredentials
 			if creds != nil {
 				credsClone = creds.Clone()
@@ -300,29 +388,23 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 				return
 			}
 			ch := cc.dopts.balancer.Notify()
-			if ch == nil {
+			if ch != nil {
-				// There is no name resolver installed.
+				if cc.dopts.block {
-				addrs = append(addrs, Address{Addr: target})
+					doneChan := make(chan struct{})
+					go cc.lbWatcher(doneChan)
+					<-doneChan
 				} else {
-				addrs, ok = <-ch
+					go cc.lbWatcher(nil)
-				if !ok || len(addrs) == 0 {
+				}
-					waitC <- errNoAddr
 				return
 			}
 		}
-		}
+		// No balancer, or no resolver within the balancer.  Connect directly.
-		for _, a := range addrs {
+		if err := cc.resetAddrConn(Address{Addr: target}, cc.dopts.block, nil); err != nil {
-			if err := cc.resetAddrConn(a, false, nil); err != nil {
 			waitC <- err
 			return
 		}
-		}
-		close(waitC)
 	}()
-	var timeoutCh <-chan time.Time
-	if cc.dopts.timeout > 0 {
-		timeoutCh = time.After(cc.dopts.timeout)
-	}
 	select {
 	case <-ctx.Done():
 		return nil, ctx.Err()
@@ -330,14 +412,12 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 		if err != nil {
 			return nil, err
 		}
-	case <-timeoutCh:
-		return nil, ErrClientConnTimeout
 	}
-	// If balancer is nil or balancer.Notify() is nil, ok will be false here.
+
-	// The lbWatcher goroutine will not be created.
+	if cc.dopts.scChan != nil {
-	if ok {
+		go cc.scWatcher()
-		go cc.lbWatcher()
 	}
+
 	return cc, nil
 }
 
@@ -384,10 +464,16 @@ type ClientConn struct {
 	dopts     dialOptions
 
 	mu    sync.RWMutex
+	sc    ServiceConfig
 	conns map[Address]*addrConn
+	// Keepalive parameter can be udated if a GoAway is received.
+	mkp keepalive.ClientParameters
 }
 
-func (cc *ClientConn) lbWatcher() {
+// lbWatcher watches the Notify channel of the balancer in cc and manages
+// connections accordingly.  If doneChan is not nil, it is closed after the
+// first successfull connection is made.
+func (cc *ClientConn) lbWatcher(doneChan chan struct{}) {
 	for addrs := range cc.dopts.balancer.Notify() {
 		var (
 			add []Address   // Addresses need to setup connections.
@@ -414,7 +500,15 @@ func (cc *ClientConn) lbWatcher() {
 		}
 		cc.mu.Unlock()
 		for _, a := range add {
-			cc.resetAddrConn(a, true, nil)
+			if doneChan != nil {
+				err := cc.resetAddrConn(a, true, nil)
+				if err == nil {
+					close(doneChan)
+					doneChan = nil
+				}
+			} else {
+				cc.resetAddrConn(a, false, nil)
+			}
 		}
 		for _, c := range del {
 			c.tearDown(errConnDrain)
@@ -422,15 +516,36 @@ func (cc *ClientConn) lbWatcher() {
 	}
 }
 
+func (cc *ClientConn) scWatcher() {
+	for {
+		select {
+		case sc, ok := <-cc.dopts.scChan:
+			if !ok {
+				return
+			}
+			cc.mu.Lock()
+			// TODO: load balance policy runtime change is ignored.
+			// We may revist this decision in the future.
+			cc.sc = sc
+			cc.mu.Unlock()
+		case <-cc.ctx.Done():
+			return
+		}
+	}
+}
+
 // resetAddrConn creates an addrConn for addr and adds it to cc.conns.
 // If there is an old addrConn for addr, it will be torn down, using tearDownErr as the reason.
 // If tearDownErr is nil, errConnDrain will be used instead.
-func (cc *ClientConn) resetAddrConn(addr Address, skipWait bool, tearDownErr error) error {
+func (cc *ClientConn) resetAddrConn(addr Address, block bool, tearDownErr error) error {
 	ac := &addrConn{
 		cc:    cc,
 		addr:  addr,
 		dopts: cc.dopts,
 	}
+	cc.mu.RLock()
+	ac.dopts.copts.KeepaliveParams = cc.mkp
+	cc.mu.RUnlock()
 	ac.ctx, ac.cancel = context.WithCancel(cc.ctx)
 	ac.stateCV = sync.NewCond(&ac.mu)
 	if EnableTracing {
@@ -475,8 +590,7 @@ func (cc *ClientConn) resetAddrConn(addr Address, skipWait bool, tearDownErr err
 			stale.tearDown(tearDownErr)
 		}
 	}
-	// skipWait may overwrite the decision in ac.dopts.block.
+	if block {
-	if ac.dopts.block && !skipWait {
 		if err := ac.resetTransport(false); err != nil {
 			if err != errConnClosing {
 				// Tear down ac and delete it from cc.conns.
@@ -509,6 +623,14 @@ func (cc *ClientConn) resetAddrConn(addr Address, skipWait bool, tearDownErr err
 	return nil
 }
 
+// TODO: Avoid the locking here.
+func (cc *ClientConn) getMethodConfig(method string) (m MethodConfig, ok bool) {
+	cc.mu.RLock()
+	defer cc.mu.RUnlock()
+	m, ok = cc.sc.Methods[method]
+	return
+}
+
 func (cc *ClientConn) getTransport(ctx context.Context, opts BalancerGetOptions) (transport.ClientTransport, func(), error) {
 	var (
 		ac  *addrConn
@@ -547,6 +669,7 @@ func (cc *ClientConn) getTransport(ctx context.Context, opts BalancerGetOptions)
 	}
 	if !ok {
 		if put != nil {
+			updateRPCInfoInContext(ctx, rpcInfo{bytesSent: false, bytesReceived: false})
 			put()
 		}
 		return nil, nil, errConnClosing
@@ -554,6 +677,7 @@ func (cc *ClientConn) getTransport(ctx context.Context, opts BalancerGetOptions)
 	t, err := ac.wait(ctx, cc.dopts.balancer != nil, !opts.BlockingWait)
 	if err != nil {
 		if put != nil {
+			updateRPCInfoInContext(ctx, rpcInfo{bytesSent: false, bytesReceived: false})
 			put()
 		}
 		return nil, nil, err
@@ -605,6 +729,20 @@ type addrConn struct {
 	tearDownErr error
 }
 
+// adjustParams updates parameters used to create transports upon
+// receiving a GoAway.
+func (ac *addrConn) adjustParams(r transport.GoAwayReason) {
+	switch r {
+	case transport.TooManyPings:
+		v := 2 * ac.dopts.copts.KeepaliveParams.Time
+		ac.cc.mu.Lock()
+		if v > ac.cc.mkp.Time {
+			ac.cc.mkp.Time = v
+		}
+		ac.cc.mu.Unlock()
+	}
+}
+
 // printf records an event in ac's event log, unless ac has been closed.
 // REQUIRES ac.mu is held.
 func (ac *addrConn) printf(format string, a ...interface{}) {
@@ -689,6 +827,8 @@ func (ac *addrConn) resetTransport(closeTransport bool) error {
 			Metadata: ac.addr.Metadata,
 		}
 		newTransport, err := transport.NewClientTransport(ctx, sinfo, ac.dopts.copts)
+		// Don't call cancel in success path due to a race in Go 1.6:
+		// https://github.com/golang/go/issues/15078.
 		if err != nil {
 			cancel()
 
@@ -759,6 +899,7 @@ func (ac *addrConn) transportMonitor() {
 			}
 			return
 		case <-t.GoAway():
+			ac.adjustParams(t.GetGoAwayReason())
 			// If GoAway happens without any network I/O error, ac is closed without shutting down the
 			// underlying transport (the transport will be closed when all the pending RPCs finished or
 			// failed.).
@@ -767,9 +908,9 @@ func (ac *addrConn) transportMonitor() {
 			// In both cases, a new ac is created.
 			select {
 			case <-t.Error():
-				ac.cc.resetAddrConn(ac.addr, true, errNetworkIO)
+				ac.cc.resetAddrConn(ac.addr, false, errNetworkIO)
 			default:
-				ac.cc.resetAddrConn(ac.addr, true, errConnDrain)
+				ac.cc.resetAddrConn(ac.addr, false, errConnDrain)
 			}
 			return
 		case <-t.Error():
@@ -778,7 +919,8 @@ func (ac *addrConn) transportMonitor() {
 				t.Close()
 				return
 			case <-t.GoAway():
-				ac.cc.resetAddrConn(ac.addr, true, errNetworkIO)
+				ac.adjustParams(t.GetGoAwayReason())
+				ac.cc.resetAddrConn(ac.addr, false, errNetworkIO)
 				return
 			default:
 			}

vendor/google.golang.org/grpc/codec.go

@@ -0,0 +1,118 @@
+/*
+*
+ * Copyright 2014, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+*/
+
+package grpc
+
+import (
+	"math"
+	"sync"
+
+	"github.com/golang/protobuf/proto"
+)
+
+// Codec defines the interface gRPC uses to encode and decode messages.
+// Note that implementations of this interface must be thread safe;
+// a Codec's methods can be called from concurrent goroutines.
+type Codec interface {
+	// Marshal returns the wire format of v.
+	Marshal(v interface{}) ([]byte, error)
+	// Unmarshal parses the wire format into v.
+	Unmarshal(data []byte, v interface{}) error
+	// String returns the name of the Codec implementation. The returned
+	// string will be used as part of content type in transmission.
+	String() string
+}
+
+// protoCodec is a Codec implementation with protobuf. It is the default codec for gRPC.
+type protoCodec struct {
+}
+
+type cachedProtoBuffer struct {
+	lastMarshaledSize uint32
+	proto.Buffer
+}
+
+func capToMaxInt32(val int) uint32 {
+	if val > math.MaxInt32 {
+		return uint32(math.MaxInt32)
+	}
+	return uint32(val)
+}
+
+func (p protoCodec) marshal(v interface{}, cb *cachedProtoBuffer) ([]byte, error) {
+	protoMsg := v.(proto.Message)
+	newSlice := make([]byte, 0, cb.lastMarshaledSize)
+
+	cb.SetBuf(newSlice)
+	cb.Reset()
+	if err := cb.Marshal(protoMsg); err != nil {
+		return nil, err
+	}
+	out := cb.Bytes()
+	cb.lastMarshaledSize = capToMaxInt32(len(out))
+	return out, nil
+}
+
+func (p protoCodec) Marshal(v interface{}) ([]byte, error) {
+	cb := protoBufferPool.Get().(*cachedProtoBuffer)
+	out, err := p.marshal(v, cb)
+
+	// put back buffer and lose the ref to the slice
+	cb.SetBuf(nil)
+	protoBufferPool.Put(cb)
+	return out, err
+}
+
+func (p protoCodec) Unmarshal(data []byte, v interface{}) error {
+	cb := protoBufferPool.Get().(*cachedProtoBuffer)
+	cb.SetBuf(data)
+	err := cb.Unmarshal(v.(proto.Message))
+	cb.SetBuf(nil)
+	protoBufferPool.Put(cb)
+	return err
+}
+
+func (protoCodec) String() string {
+	return "proto"
+}
+
+var (
+	protoBufferPool = &sync.Pool{
+		New: func() interface{} {
+			return &cachedProtoBuffer{
+				Buffer:            proto.Buffer{},
+				lastMarshaledSize: 16,
+			}
+		},
+	}
+)

vendor/google.golang.org/grpc/credentials/credentials.go

@@ -102,6 +102,10 @@ type TransportCredentials interface {
 	// authentication protocol on rawConn for clients. It returns the authenticated
 	// connection and the corresponding auth information about the connection.
 	// Implementations must use the provided context to implement timely cancellation.
+	// gRPC will try to reconnect if the error returned is a temporary error
+	// (io.EOF, context.DeadlineExceeded or err.Temporary() == true).
+	// If the returned error is a wrapper error, implementations should make sure that
+	// the error implements Temporary() to have the correct retry behaviors.
 	ClientHandshake(context.Context, string, net.Conn) (net.Conn, AuthInfo, error)
 	// ServerHandshake does the authentication handshake for servers. It returns
 	// the authenticated connection and the corresponding auth information about
@@ -165,9 +169,7 @@ func (c *tlsCreds) ClientHandshake(ctx context.Context, addr string, rawConn net
 	case <-ctx.Done():
 		return nil, nil, ctx.Err()
 	}
-	// TODO(zhaoq): Omit the auth info for client now. It is more for
+	return conn, TLSInfo{conn.ConnectionState()}, nil
-	// information than anything else.
-	return conn, nil, nil
 }
 
 func (c *tlsCreds) ServerHandshake(rawConn net.Conn) (net.Conn, AuthInfo, error) {

vendor/google.golang.org/grpc/credentials/credentials_util_go17.go

@@ -1,4 +1,5 @@
 // +build go1.7
+// +build !go1.8
 
 /*
  *
@@ -44,8 +45,6 @@ import (
 // contains a mutex and must not be copied.
 //
 // If cfg is nil, a new zero tls.Config is returned.
-//
-// TODO replace this function with official clone function.
 func cloneTLSConfig(cfg *tls.Config) *tls.Config {
 	if cfg == nil {
 		return &tls.Config{}

vendor/google.golang.org/grpc/credentials/credentials_util_go18.go

@@ -0,0 +1,53 @@
+// +build go1.8
+
+/*
+ *
+ * Copyright 2017, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+package credentials
+
+import (
+	"crypto/tls"
+)
+
+// cloneTLSConfig returns a shallow clone of the exported
+// fields of cfg, ignoring the unexported sync.Once, which
+// contains a mutex and must not be copied.
+//
+// If cfg is nil, a new zero tls.Config is returned.
+func cloneTLSConfig(cfg *tls.Config) *tls.Config {
+	if cfg == nil {
+		return &tls.Config{}
+	}
+
+	return cfg.Clone()
+}

vendor/google.golang.org/grpc/credentials/credentials_util_pre_go17.go

@@ -44,8 +44,6 @@ import (
 // contains a mutex and must not be copied.
 //
 // If cfg is nil, a new zero tls.Config is returned.
-//
-// TODO replace this function with official clone function.
 func cloneTLSConfig(cfg *tls.Config) *tls.Config {
 	if cfg == nil {
 		return &tls.Config{}

vendor/google.golang.org/grpc/go16.go

@@ -0,0 +1,56 @@
+// +build go1.6,!go1.7
+
+/*
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+package grpc
+
+import (
+	"fmt"
+	"net"
+	"net/http"
+
+	"golang.org/x/net/context"
+)
+
+// dialContext connects to the address on the named network.
+func dialContext(ctx context.Context, network, address string) (net.Conn, error) {
+	return (&net.Dialer{Cancel: ctx.Done()}).Dial(network, address)
+}
+
+func sendHTTPRequest(ctx context.Context, req *http.Request, conn net.Conn) error {
+	req.Cancel = ctx.Done()
+	if err := req.Write(conn); err != nil {
+		return fmt.Errorf("failed to write the HTTP request: %v", err)
+	}
+	return nil
+}

vendor/google.golang.org/grpc/go17.go

@@ -1,4 +1,4 @@
-// +build !go1.6
+// +build go1.7
 
 /*
  * Copyright 2016, Google Inc.
@@ -32,20 +32,24 @@
  *
  */
 
-package transport
+package grpc
 
 import (
 	"net"
-	"time"
+	"net/http"
 
 	"golang.org/x/net/context"
 )
 
 // dialContext connects to the address on the named network.
 func dialContext(ctx context.Context, network, address string) (net.Conn, error) {
-	var dialer net.Dialer
+	return (&net.Dialer{}).DialContext(ctx, network, address)
-	if deadline, ok := ctx.Deadline(); ok {
+}
-		dialer.Timeout = deadline.Sub(time.Now())
+
-	}
+func sendHTTPRequest(ctx context.Context, req *http.Request, conn net.Conn) error {
-	return dialer.Dial(network, address)
+	req = req.WithContext(ctx)
+	if err := req.Write(conn); err != nil {
+		return err
+	}
+	return nil
 }

vendor/google.golang.org/grpc/grpclb.go

@@ -0,0 +1,749 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+package grpc
+
+import (
+	"errors"
+	"fmt"
+	"math/rand"
+	"net"
+	"sync"
+	"time"
+
+	"golang.org/x/net/context"
+	"google.golang.org/grpc/codes"
+	lbpb "google.golang.org/grpc/grpclb/grpc_lb_v1"
+	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/naming"
+)
+
+// Client API for LoadBalancer service.
+// Mostly copied from generated pb.go file.
+// To avoid circular dependency.
+type loadBalancerClient struct {
+	cc *ClientConn
+}
+
+func (c *loadBalancerClient) BalanceLoad(ctx context.Context, opts ...CallOption) (*balanceLoadClientStream, error) {
+	desc := &StreamDesc{
+		StreamName:    "BalanceLoad",
+		ServerStreams: true,
+		ClientStreams: true,
+	}
+	stream, err := NewClientStream(ctx, desc, c.cc, "/grpc.lb.v1.LoadBalancer/BalanceLoad", opts...)
+	if err != nil {
+		return nil, err
+	}
+	x := &balanceLoadClientStream{stream}
+	return x, nil
+}
+
+type balanceLoadClientStream struct {
+	ClientStream
+}
+
+func (x *balanceLoadClientStream) Send(m *lbpb.LoadBalanceRequest) error {
+	return x.ClientStream.SendMsg(m)
+}
+
+func (x *balanceLoadClientStream) Recv() (*lbpb.LoadBalanceResponse, error) {
+	m := new(lbpb.LoadBalanceResponse)
+	if err := x.ClientStream.RecvMsg(m); err != nil {
+		return nil, err
+	}
+	return m, nil
+}
+
+// AddressType indicates the address type returned by name resolution.
+type AddressType uint8
+
+const (
+	// Backend indicates the server is a backend server.
+	Backend AddressType = iota
+	// GRPCLB indicates the server is a grpclb load balancer.
+	GRPCLB
+)
+
+// AddrMetadataGRPCLB contains the information the name resolution for grpclb should provide. The
+// name resolver used by grpclb balancer is required to provide this type of metadata in
+// its address updates.
+type AddrMetadataGRPCLB struct {
+	// AddrType is the type of server (grpc load balancer or backend).
+	AddrType AddressType
+	// ServerName is the name of the grpc load balancer. Used for authentication.
+	ServerName string
+}
+
+// NewGRPCLBBalancer creates a grpclb load balancer.
+func NewGRPCLBBalancer(r naming.Resolver) Balancer {
+	return &balancer{
+		r: r,
+	}
+}
+
+type remoteBalancerInfo struct {
+	addr string
+	// the server name used for authentication with the remote LB server.
+	name string
+}
+
+// grpclbAddrInfo consists of the information of a backend server.
+type grpclbAddrInfo struct {
+	addr      Address
+	connected bool
+	// dropForRateLimiting indicates whether this particular request should be
+	// dropped by the client for rate limiting.
+	dropForRateLimiting bool
+	// dropForLoadBalancing indicates whether this particular request should be
+	// dropped by the client for load balancing.
+	dropForLoadBalancing bool
+}
+
+type balancer struct {
+	r        naming.Resolver
+	target   string
+	mu       sync.Mutex
+	seq      int // a sequence number to make sure addrCh does not get stale addresses.
+	w        naming.Watcher
+	addrCh   chan []Address
+	rbs      []remoteBalancerInfo
+	addrs    []*grpclbAddrInfo
+	next     int
+	waitCh   chan struct{}
+	done     bool
+	expTimer *time.Timer
+	rand     *rand.Rand
+
+	clientStats lbpb.ClientStats
+}
+
+func (b *balancer) watchAddrUpdates(w naming.Watcher, ch chan []remoteBalancerInfo) error {
+	updates, err := w.Next()
+	if err != nil {
+		return err
+	}
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	if b.done {
+		return ErrClientConnClosing
+	}
+	for _, update := range updates {
+		switch update.Op {
+		case naming.Add:
+			var exist bool
+			for _, v := range b.rbs {
+				// TODO: Is the same addr with different server name a different balancer?
+				if update.Addr == v.addr {
+					exist = true
+					break
+				}
+			}
+			if exist {
+				continue
+			}
+			md, ok := update.Metadata.(*AddrMetadataGRPCLB)
+			if !ok {
+				// TODO: Revisit the handling here and may introduce some fallback mechanism.
+				grpclog.Printf("The name resolution contains unexpected metadata %v", update.Metadata)
+				continue
+			}
+			switch md.AddrType {
+			case Backend:
+				// TODO: Revisit the handling here and may introduce some fallback mechanism.
+				grpclog.Printf("The name resolution does not give grpclb addresses")
+				continue
+			case GRPCLB:
+				b.rbs = append(b.rbs, remoteBalancerInfo{
+					addr: update.Addr,
+					name: md.ServerName,
+				})
+			default:
+				grpclog.Printf("Received unknow address type %d", md.AddrType)
+				continue
+			}
+		case naming.Delete:
+			for i, v := range b.rbs {
+				if update.Addr == v.addr {
+					copy(b.rbs[i:], b.rbs[i+1:])
+					b.rbs = b.rbs[:len(b.rbs)-1]
+					break
+				}
+			}
+		default:
+			grpclog.Println("Unknown update.Op ", update.Op)
+		}
+	}
+	// TODO: Fall back to the basic round-robin load balancing if the resulting address is
+	// not a load balancer.
+	select {
+	case <-ch:
+	default:
+	}
+	ch <- b.rbs
+	return nil
+}
+
+func (b *balancer) serverListExpire(seq int) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	// TODO: gRPC interanls do not clear the connections when the server list is stale.
+	// This means RPCs will keep using the existing server list until b receives new
+	// server list even though the list is expired. Revisit this behavior later.
+	if b.done || seq < b.seq {
+		return
+	}
+	b.next = 0
+	b.addrs = nil
+	// Ask grpc internals to close all the corresponding connections.
+	b.addrCh <- nil
+}
+
+func convertDuration(d *lbpb.Duration) time.Duration {
+	if d == nil {
+		return 0
+	}
+	return time.Duration(d.Seconds)*time.Second + time.Duration(d.Nanos)*time.Nanosecond
+}
+
+func (b *balancer) processServerList(l *lbpb.ServerList, seq int) {
+	if l == nil {
+		return
+	}
+	servers := l.GetServers()
+	expiration := convertDuration(l.GetExpirationInterval())
+	var (
+		sl    []*grpclbAddrInfo
+		addrs []Address
+	)
+	for _, s := range servers {
+		md := metadata.Pairs("lb-token", s.LoadBalanceToken)
+		addr := Address{
+			Addr:     fmt.Sprintf("%s:%d", net.IP(s.IpAddress), s.Port),
+			Metadata: &md,
+		}
+		sl = append(sl, &grpclbAddrInfo{
+			addr:                 addr,
+			dropForRateLimiting:  s.DropForRateLimiting,
+			dropForLoadBalancing: s.DropForLoadBalancing,
+		})
+		addrs = append(addrs, addr)
+	}
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	if b.done || seq < b.seq {
+		return
+	}
+	if len(sl) > 0 {
+		// reset b.next to 0 when replacing the server list.
+		b.next = 0
+		b.addrs = sl
+		b.addrCh <- addrs
+		if b.expTimer != nil {
+			b.expTimer.Stop()
+			b.expTimer = nil
+		}
+		if expiration > 0 {
+			b.expTimer = time.AfterFunc(expiration, func() {
+				b.serverListExpire(seq)
+			})
+		}
+	}
+	return
+}
+
+func (b *balancer) sendLoadReport(s *balanceLoadClientStream, interval time.Duration, done <-chan struct{}) {
+	ticker := time.NewTicker(interval)
+	defer ticker.Stop()
+	for {
+		select {
+		case <-ticker.C:
+		case <-done:
+			return
+		}
+		b.mu.Lock()
+		stats := b.clientStats
+		b.clientStats = lbpb.ClientStats{} // Clear the stats.
+		b.mu.Unlock()
+		t := time.Now()
+		stats.Timestamp = &lbpb.Timestamp{
+			Seconds: t.Unix(),
+			Nanos:   int32(t.Nanosecond()),
+		}
+		if err := s.Send(&lbpb.LoadBalanceRequest{
+			LoadBalanceRequestType: &lbpb.LoadBalanceRequest_ClientStats{
+				ClientStats: &stats,
+			},
+		}); err != nil {
+			return
+		}
+	}
+}
+
+func (b *balancer) callRemoteBalancer(lbc *loadBalancerClient, seq int) (retry bool) {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	stream, err := lbc.BalanceLoad(ctx)
+	if err != nil {
+		grpclog.Printf("Failed to perform RPC to the remote balancer %v", err)
+		return
+	}
+	b.mu.Lock()
+	if b.done {
+		b.mu.Unlock()
+		return
+	}
+	b.mu.Unlock()
+	initReq := &lbpb.LoadBalanceRequest{
+		LoadBalanceRequestType: &lbpb.LoadBalanceRequest_InitialRequest{
+			InitialRequest: &lbpb.InitialLoadBalanceRequest{
+				Name: b.target,
+			},
+		},
+	}
+	if err := stream.Send(initReq); err != nil {
+		// TODO: backoff on retry?
+		return true
+	}
+	reply, err := stream.Recv()
+	if err != nil {
+		// TODO: backoff on retry?
+		return true
+	}
+	initResp := reply.GetInitialResponse()
+	if initResp == nil {
+		grpclog.Println("Failed to receive the initial response from the remote balancer.")
+		return
+	}
+	// TODO: Support delegation.
+	if initResp.LoadBalancerDelegate != "" {
+		// delegation
+		grpclog.Println("TODO: Delegation is not supported yet.")
+		return
+	}
+	streamDone := make(chan struct{})
+	defer close(streamDone)
+	b.mu.Lock()
+	b.clientStats = lbpb.ClientStats{} // Clear client stats.
+	b.mu.Unlock()
+	if d := convertDuration(initResp.ClientStatsReportInterval); d > 0 {
+		go b.sendLoadReport(stream, d, streamDone)
+	}
+	// Retrieve the server list.
+	for {
+		reply, err := stream.Recv()
+		if err != nil {
+			break
+		}
+		b.mu.Lock()
+		if b.done || seq < b.seq {
+			b.mu.Unlock()
+			return
+		}
+		b.seq++ // tick when receiving a new list of servers.
+		seq = b.seq
+		b.mu.Unlock()
+		if serverList := reply.GetServerList(); serverList != nil {
+			b.processServerList(serverList, seq)
+		}
+	}
+	return true
+}
+
+func (b *balancer) Start(target string, config BalancerConfig) error {
+	b.rand = rand.New(rand.NewSource(time.Now().Unix()))
+	// TODO: Fall back to the basic direct connection if there is no name resolver.
+	if b.r == nil {
+		return errors.New("there is no name resolver installed")
+	}
+	b.target = target
+	b.mu.Lock()
+	if b.done {
+		b.mu.Unlock()
+		return ErrClientConnClosing
+	}
+	b.addrCh = make(chan []Address)
+	w, err := b.r.Resolve(target)
+	if err != nil {
+		b.mu.Unlock()
+		return err
+	}
+	b.w = w
+	b.mu.Unlock()
+	balancerAddrsCh := make(chan []remoteBalancerInfo, 1)
+	// Spawn a goroutine to monitor the name resolution of remote load balancer.
+	go func() {
+		for {
+			if err := b.watchAddrUpdates(w, balancerAddrsCh); err != nil {
+				grpclog.Printf("grpc: the naming watcher stops working due to %v.\n", err)
+				close(balancerAddrsCh)
+				return
+			}
+		}
+	}()
+	// Spawn a goroutine to talk to the remote load balancer.
+	go func() {
+		var (
+			cc *ClientConn
+			// ccError is closed when there is an error in the current cc.
+			// A new rb should be picked from rbs and connected.
+			ccError chan struct{}
+			rb      *remoteBalancerInfo
+			rbs     []remoteBalancerInfo
+			rbIdx   int
+		)
+
+		defer func() {
+			if ccError != nil {
+				select {
+				case <-ccError:
+				default:
+					close(ccError)
+				}
+			}
+			if cc != nil {
+				cc.Close()
+			}
+		}()
+
+		for {
+			var ok bool
+			select {
+			case rbs, ok = <-balancerAddrsCh:
+				if !ok {
+					return
+				}
+				foundIdx := -1
+				if rb != nil {
+					for i, trb := range rbs {
+						if trb == *rb {
+							foundIdx = i
+							break
+						}
+					}
+				}
+				if foundIdx >= 0 {
+					if foundIdx >= 1 {
+						// Move the address in use to the beginning of the list.
+						b.rbs[0], b.rbs[foundIdx] = b.rbs[foundIdx], b.rbs[0]
+						rbIdx = 0
+					}
+					continue // If found, don't dial new cc.
+				} else if len(rbs) > 0 {
+					// Pick a random one from the list, instead of always using the first one.
+					if l := len(rbs); l > 1 && rb != nil {
+						tmpIdx := b.rand.Intn(l - 1)
+						b.rbs[0], b.rbs[tmpIdx] = b.rbs[tmpIdx], b.rbs[0]
+					}
+					rbIdx = 0
+					rb = &rbs[0]
+				} else {
+					// foundIdx < 0 && len(rbs) <= 0.
+					rb = nil
+				}
+			case <-ccError:
+				ccError = nil
+				if rbIdx < len(rbs)-1 {
+					rbIdx++
+					rb = &rbs[rbIdx]
+				} else {
+					rb = nil
+				}
+			}
+
+			if rb == nil {
+				continue
+			}
+
+			if cc != nil {
+				cc.Close()
+			}
+			// Talk to the remote load balancer to get the server list.
+			var err error
+			creds := config.DialCreds
+			ccError = make(chan struct{})
+			if creds == nil {
+				cc, err = Dial(rb.addr, WithInsecure())
+			} else {
+				if rb.name != "" {
+					if err := creds.OverrideServerName(rb.name); err != nil {
+						grpclog.Printf("Failed to override the server name in the credentials: %v", err)
+						continue
+					}
+				}
+				cc, err = Dial(rb.addr, WithTransportCredentials(creds))
+			}
+			if err != nil {
+				grpclog.Printf("Failed to setup a connection to the remote balancer %v: %v", rb.addr, err)
+				close(ccError)
+				continue
+			}
+			b.mu.Lock()
+			b.seq++ // tick when getting a new balancer address
+			seq := b.seq
+			b.next = 0
+			b.mu.Unlock()
+			go func(cc *ClientConn, ccError chan struct{}) {
+				lbc := &loadBalancerClient{cc}
+				b.callRemoteBalancer(lbc, seq)
+				cc.Close()
+				select {
+				case <-ccError:
+				default:
+					close(ccError)
+				}
+			}(cc, ccError)
+		}
+	}()
+	return nil
+}
+
+func (b *balancer) down(addr Address, err error) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	for _, a := range b.addrs {
+		if addr == a.addr {
+			a.connected = false
+			break
+		}
+	}
+}
+
+func (b *balancer) Up(addr Address) func(error) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	if b.done {
+		return nil
+	}
+	var cnt int
+	for _, a := range b.addrs {
+		if a.addr == addr {
+			if a.connected {
+				return nil
+			}
+			a.connected = true
+		}
+		if a.connected && !a.dropForRateLimiting && !a.dropForLoadBalancing {
+			cnt++
+		}
+	}
+	// addr is the only one which is connected. Notify the Get() callers who are blocking.
+	if cnt == 1 && b.waitCh != nil {
+		close(b.waitCh)
+		b.waitCh = nil
+	}
+	return func(err error) {
+		b.down(addr, err)
+	}
+}
+
+func (b *balancer) Get(ctx context.Context, opts BalancerGetOptions) (addr Address, put func(), err error) {
+	var ch chan struct{}
+	b.mu.Lock()
+	if b.done {
+		b.mu.Unlock()
+		err = ErrClientConnClosing
+		return
+	}
+	seq := b.seq
+
+	defer func() {
+		if err != nil {
+			return
+		}
+		put = func() {
+			s, ok := rpcInfoFromContext(ctx)
+			if !ok {
+				return
+			}
+			b.mu.Lock()
+			defer b.mu.Unlock()
+			if b.done || seq < b.seq {
+				return
+			}
+			b.clientStats.NumCallsFinished++
+			if !s.bytesSent {
+				b.clientStats.NumCallsFinishedWithClientFailedToSend++
+			} else if s.bytesReceived {
+				b.clientStats.NumCallsFinishedKnownReceived++
+			}
+		}
+	}()
+
+	b.clientStats.NumCallsStarted++
+	if len(b.addrs) > 0 {
+		if b.next >= len(b.addrs) {
+			b.next = 0
+		}
+		next := b.next
+		for {
+			a := b.addrs[next]
+			next = (next + 1) % len(b.addrs)
+			if a.connected {
+				if !a.dropForRateLimiting && !a.dropForLoadBalancing {
+					addr = a.addr
+					b.next = next
+					b.mu.Unlock()
+					return
+				}
+				if !opts.BlockingWait {
+					b.next = next
+					if a.dropForLoadBalancing {
+						b.clientStats.NumCallsFinished++
+						b.clientStats.NumCallsFinishedWithDropForLoadBalancing++
+					} else if a.dropForRateLimiting {
+						b.clientStats.NumCallsFinished++
+						b.clientStats.NumCallsFinishedWithDropForRateLimiting++
+					}
+					b.mu.Unlock()
+					err = Errorf(codes.Unavailable, "%s drops requests", a.addr.Addr)
+					return
+				}
+			}
+			if next == b.next {
+				// Has iterated all the possible address but none is connected.
+				break
+			}
+		}
+	}
+	if !opts.BlockingWait {
+		if len(b.addrs) == 0 {
+			b.clientStats.NumCallsFinished++
+			b.clientStats.NumCallsFinishedWithClientFailedToSend++
+			b.mu.Unlock()
+			err = Errorf(codes.Unavailable, "there is no address available")
+			return
+		}
+		// Returns the next addr on b.addrs for a failfast RPC.
+		addr = b.addrs[b.next].addr
+		b.next++
+		b.mu.Unlock()
+		return
+	}
+	// Wait on b.waitCh for non-failfast RPCs.
+	if b.waitCh == nil {
+		ch = make(chan struct{})
+		b.waitCh = ch
+	} else {
+		ch = b.waitCh
+	}
+	b.mu.Unlock()
+	for {
+		select {
+		case <-ctx.Done():
+			b.mu.Lock()
+			b.clientStats.NumCallsFinished++
+			b.clientStats.NumCallsFinishedWithClientFailedToSend++
+			b.mu.Unlock()
+			err = ctx.Err()
+			return
+		case <-ch:
+			b.mu.Lock()
+			if b.done {
+				b.clientStats.NumCallsFinished++
+				b.clientStats.NumCallsFinishedWithClientFailedToSend++
+				b.mu.Unlock()
+				err = ErrClientConnClosing
+				return
+			}
+
+			if len(b.addrs) > 0 {
+				if b.next >= len(b.addrs) {
+					b.next = 0
+				}
+				next := b.next
+				for {
+					a := b.addrs[next]
+					next = (next + 1) % len(b.addrs)
+					if a.connected {
+						if !a.dropForRateLimiting && !a.dropForLoadBalancing {
+							addr = a.addr
+							b.next = next
+							b.mu.Unlock()
+							return
+						}
+						if !opts.BlockingWait {
+							b.next = next
+							if a.dropForLoadBalancing {
+								b.clientStats.NumCallsFinished++
+								b.clientStats.NumCallsFinishedWithDropForLoadBalancing++
+							} else if a.dropForRateLimiting {
+								b.clientStats.NumCallsFinished++
+								b.clientStats.NumCallsFinishedWithDropForRateLimiting++
+							}
+							b.mu.Unlock()
+							err = Errorf(codes.Unavailable, "drop requests for the addreess %s", a.addr.Addr)
+							return
+						}
+					}
+					if next == b.next {
+						// Has iterated all the possible address but none is connected.
+						break
+					}
+				}
+			}
+			// The newly added addr got removed by Down() again.
+			if b.waitCh == nil {
+				ch = make(chan struct{})
+				b.waitCh = ch
+			} else {
+				ch = b.waitCh
+			}
+			b.mu.Unlock()
+		}
+	}
+}
+
+func (b *balancer) Notify() <-chan []Address {
+	return b.addrCh
+}
+
+func (b *balancer) Close() error {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	b.done = true
+	if b.expTimer != nil {
+		b.expTimer.Stop()
+	}
+	if b.waitCh != nil {
+		close(b.waitCh)
+	}
+	if b.addrCh != nil {
+		close(b.addrCh)
+	}
+	if b.w != nil {
+		b.w.Close()
+	}
+	return nil
+}

vendor/google.golang.org/grpc/grpclb/grpc_lb_v1/grpclb.pb.go

@@ -0,0 +1,629 @@
+// Code generated by protoc-gen-go.
+// source: grpclb.proto
+// DO NOT EDIT!
+
+/*
+Package grpc_lb_v1 is a generated protocol buffer package.
+
+It is generated from these files:
+	grpclb.proto
+
+It has these top-level messages:
+	Duration
+	Timestamp
+	LoadBalanceRequest
+	InitialLoadBalanceRequest
+	ClientStats
+	LoadBalanceResponse
+	InitialLoadBalanceResponse
+	ServerList
+	Server
+*/
+package grpc_lb_v1
+
+import proto "github.com/golang/protobuf/proto"
+import fmt "fmt"
+import math "math"
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = fmt.Errorf
+var _ = math.Inf
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the proto package it is being compiled against.
+// A compilation error at this line likely means your copy of the
+// proto package needs to be updated.
+const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package
+
+type Duration struct {
+	// Signed seconds of the span of time. Must be from -315,576,000,000
+	// to +315,576,000,000 inclusive.
+	Seconds int64 `protobuf:"varint,1,opt,name=seconds" json:"seconds,omitempty"`
+	// Signed fractions of a second at nanosecond resolution of the span
+	// of time. Durations less than one second are represented with a 0
+	// `seconds` field and a positive or negative `nanos` field. For durations
+	// of one second or more, a non-zero value for the `nanos` field must be
+	// of the same sign as the `seconds` field. Must be from -999,999,999
+	// to +999,999,999 inclusive.
+	Nanos int32 `protobuf:"varint,2,opt,name=nanos" json:"nanos,omitempty"`
+}
+
+func (m *Duration) Reset()                    { *m = Duration{} }
+func (m *Duration) String() string            { return proto.CompactTextString(m) }
+func (*Duration) ProtoMessage()               {}
+func (*Duration) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{0} }
+
+func (m *Duration) GetSeconds() int64 {
+	if m != nil {
+		return m.Seconds
+	}
+	return 0
+}
+
+func (m *Duration) GetNanos() int32 {
+	if m != nil {
+		return m.Nanos
+	}
+	return 0
+}
+
+type Timestamp struct {
+	// Represents seconds of UTC time since Unix epoch
+	// 1970-01-01T00:00:00Z. Must be from 0001-01-01T00:00:00Z to
+	// 9999-12-31T23:59:59Z inclusive.
+	Seconds int64 `protobuf:"varint,1,opt,name=seconds" json:"seconds,omitempty"`
+	// Non-negative fractions of a second at nanosecond resolution. Negative
+	// second values with fractions must still have non-negative nanos values
+	// that count forward in time. Must be from 0 to 999,999,999
+	// inclusive.
+	Nanos int32 `protobuf:"varint,2,opt,name=nanos" json:"nanos,omitempty"`
+}
+
+func (m *Timestamp) Reset()                    { *m = Timestamp{} }
+func (m *Timestamp) String() string            { return proto.CompactTextString(m) }
+func (*Timestamp) ProtoMessage()               {}
+func (*Timestamp) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{1} }
+
+func (m *Timestamp) GetSeconds() int64 {
+	if m != nil {
+		return m.Seconds
+	}
+	return 0
+}
+
+func (m *Timestamp) GetNanos() int32 {
+	if m != nil {
+		return m.Nanos
+	}
+	return 0
+}
+
+type LoadBalanceRequest struct {
+	// Types that are valid to be assigned to LoadBalanceRequestType:
+	//	*LoadBalanceRequest_InitialRequest
+	//	*LoadBalanceRequest_ClientStats
+	LoadBalanceRequestType isLoadBalanceRequest_LoadBalanceRequestType `protobuf_oneof:"load_balance_request_type"`
+}
+
+func (m *LoadBalanceRequest) Reset()                    { *m = LoadBalanceRequest{} }
+func (m *LoadBalanceRequest) String() string            { return proto.CompactTextString(m) }
+func (*LoadBalanceRequest) ProtoMessage()               {}
+func (*LoadBalanceRequest) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{2} }
+
+type isLoadBalanceRequest_LoadBalanceRequestType interface {
+	isLoadBalanceRequest_LoadBalanceRequestType()
+}
+
+type LoadBalanceRequest_InitialRequest struct {
+	InitialRequest *InitialLoadBalanceRequest `protobuf:"bytes,1,opt,name=initial_request,json=initialRequest,oneof"`
+}
+type LoadBalanceRequest_ClientStats struct {
+	ClientStats *ClientStats `protobuf:"bytes,2,opt,name=client_stats,json=clientStats,oneof"`
+}
+
+func (*LoadBalanceRequest_InitialRequest) isLoadBalanceRequest_LoadBalanceRequestType() {}
+func (*LoadBalanceRequest_ClientStats) isLoadBalanceRequest_LoadBalanceRequestType()    {}
+
+func (m *LoadBalanceRequest) GetLoadBalanceRequestType() isLoadBalanceRequest_LoadBalanceRequestType {
+	if m != nil {
+		return m.LoadBalanceRequestType
+	}
+	return nil
+}
+
+func (m *LoadBalanceRequest) GetInitialRequest() *InitialLoadBalanceRequest {
+	if x, ok := m.GetLoadBalanceRequestType().(*LoadBalanceRequest_InitialRequest); ok {
+		return x.InitialRequest
+	}
+	return nil
+}
+
+func (m *LoadBalanceRequest) GetClientStats() *ClientStats {
+	if x, ok := m.GetLoadBalanceRequestType().(*LoadBalanceRequest_ClientStats); ok {
+		return x.ClientStats
+	}
+	return nil
+}
+
+// XXX_OneofFuncs is for the internal use of the proto package.
+func (*LoadBalanceRequest) XXX_OneofFuncs() (func(msg proto.Message, b *proto.Buffer) error, func(msg proto.Message, tag, wire int, b *proto.Buffer) (bool, error), func(msg proto.Message) (n int), []interface{}) {
+	return _LoadBalanceRequest_OneofMarshaler, _LoadBalanceRequest_OneofUnmarshaler, _LoadBalanceRequest_OneofSizer, []interface{}{
+		(*LoadBalanceRequest_InitialRequest)(nil),
+		(*LoadBalanceRequest_ClientStats)(nil),
+	}
+}
+
+func _LoadBalanceRequest_OneofMarshaler(msg proto.Message, b *proto.Buffer) error {
+	m := msg.(*LoadBalanceRequest)
+	// load_balance_request_type
+	switch x := m.LoadBalanceRequestType.(type) {
+	case *LoadBalanceRequest_InitialRequest:
+		b.EncodeVarint(1<<3 | proto.WireBytes)
+		if err := b.EncodeMessage(x.InitialRequest); err != nil {
+			return err
+		}
+	case *LoadBalanceRequest_ClientStats:
+		b.EncodeVarint(2<<3 | proto.WireBytes)
+		if err := b.EncodeMessage(x.ClientStats); err != nil {
+			return err
+		}
+	case nil:
+	default:
+		return fmt.Errorf("LoadBalanceRequest.LoadBalanceRequestType has unexpected type %T", x)
+	}
+	return nil
+}
+
+func _LoadBalanceRequest_OneofUnmarshaler(msg proto.Message, tag, wire int, b *proto.Buffer) (bool, error) {
+	m := msg.(*LoadBalanceRequest)
+	switch tag {
+	case 1: // load_balance_request_type.initial_request
+		if wire != proto.WireBytes {
+			return true, proto.ErrInternalBadWireType
+		}
+		msg := new(InitialLoadBalanceRequest)
+		err := b.DecodeMessage(msg)
+		m.LoadBalanceRequestType = &LoadBalanceRequest_InitialRequest{msg}
+		return true, err
+	case 2: // load_balance_request_type.client_stats
+		if wire != proto.WireBytes {
+			return true, proto.ErrInternalBadWireType
+		}
+		msg := new(ClientStats)
+		err := b.DecodeMessage(msg)
+		m.LoadBalanceRequestType = &LoadBalanceRequest_ClientStats{msg}
+		return true, err
+	default:
+		return false, nil
+	}
+}
+
+func _LoadBalanceRequest_OneofSizer(msg proto.Message) (n int) {
+	m := msg.(*LoadBalanceRequest)
+	// load_balance_request_type
+	switch x := m.LoadBalanceRequestType.(type) {
+	case *LoadBalanceRequest_InitialRequest:
+		s := proto.Size(x.InitialRequest)
+		n += proto.SizeVarint(1<<3 | proto.WireBytes)
+		n += proto.SizeVarint(uint64(s))
+		n += s
+	case *LoadBalanceRequest_ClientStats:
+		s := proto.Size(x.ClientStats)
+		n += proto.SizeVarint(2<<3 | proto.WireBytes)
+		n += proto.SizeVarint(uint64(s))
+		n += s
+	case nil:
+	default:
+		panic(fmt.Sprintf("proto: unexpected type %T in oneof", x))
+	}
+	return n
+}
+
+type InitialLoadBalanceRequest struct {
+	// Name of load balanced service (IE, balancer.service.com)
+	// length should be less than 256 bytes.
+	Name string `protobuf:"bytes,1,opt,name=name" json:"name,omitempty"`
+}
+
+func (m *InitialLoadBalanceRequest) Reset()                    { *m = InitialLoadBalanceRequest{} }
+func (m *InitialLoadBalanceRequest) String() string            { return proto.CompactTextString(m) }
+func (*InitialLoadBalanceRequest) ProtoMessage()               {}
+func (*InitialLoadBalanceRequest) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{3} }
+
+func (m *InitialLoadBalanceRequest) GetName() string {
+	if m != nil {
+		return m.Name
+	}
+	return ""
+}
+
+// Contains client level statistics that are useful to load balancing. Each
+// count except the timestamp should be reset to zero after reporting the stats.
+type ClientStats struct {
+	// The timestamp of generating the report.
+	Timestamp *Timestamp `protobuf:"bytes,1,opt,name=timestamp" json:"timestamp,omitempty"`
+	// The total number of RPCs that started.
+	NumCallsStarted int64 `protobuf:"varint,2,opt,name=num_calls_started,json=numCallsStarted" json:"num_calls_started,omitempty"`
+	// The total number of RPCs that finished.
+	NumCallsFinished int64 `protobuf:"varint,3,opt,name=num_calls_finished,json=numCallsFinished" json:"num_calls_finished,omitempty"`
+	// The total number of RPCs that were dropped by the client because of rate
+	// limiting.
+	NumCallsFinishedWithDropForRateLimiting int64 `protobuf:"varint,4,opt,name=num_calls_finished_with_drop_for_rate_limiting,json=numCallsFinishedWithDropForRateLimiting" json:"num_calls_finished_with_drop_for_rate_limiting,omitempty"`
+	// The total number of RPCs that were dropped by the client because of load
+	// balancing.
+	NumCallsFinishedWithDropForLoadBalancing int64 `protobuf:"varint,5,opt,name=num_calls_finished_with_drop_for_load_balancing,json=numCallsFinishedWithDropForLoadBalancing" json:"num_calls_finished_with_drop_for_load_balancing,omitempty"`
+	// The total number of RPCs that failed to reach a server except dropped RPCs.
+	NumCallsFinishedWithClientFailedToSend int64 `protobuf:"varint,6,opt,name=num_calls_finished_with_client_failed_to_send,json=numCallsFinishedWithClientFailedToSend" json:"num_calls_finished_with_client_failed_to_send,omitempty"`
+	// The total number of RPCs that finished and are known to have been received
+	// by a server.
+	NumCallsFinishedKnownReceived int64 `protobuf:"varint,7,opt,name=num_calls_finished_known_received,json=numCallsFinishedKnownReceived" json:"num_calls_finished_known_received,omitempty"`
+}
+
+func (m *ClientStats) Reset()                    { *m = ClientStats{} }
+func (m *ClientStats) String() string            { return proto.CompactTextString(m) }
+func (*ClientStats) ProtoMessage()               {}
+func (*ClientStats) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{4} }
+
+func (m *ClientStats) GetTimestamp() *Timestamp {
+	if m != nil {
+		return m.Timestamp
+	}
+	return nil
+}
+
+func (m *ClientStats) GetNumCallsStarted() int64 {
+	if m != nil {
+		return m.NumCallsStarted
+	}
+	return 0
+}
+
+func (m *ClientStats) GetNumCallsFinished() int64 {
+	if m != nil {
+		return m.NumCallsFinished
+	}
+	return 0
+}
+
+func (m *ClientStats) GetNumCallsFinishedWithDropForRateLimiting() int64 {
+	if m != nil {
+		return m.NumCallsFinishedWithDropForRateLimiting
+	}
+	return 0
+}
+
+func (m *ClientStats) GetNumCallsFinishedWithDropForLoadBalancing() int64 {
+	if m != nil {
+		return m.NumCallsFinishedWithDropForLoadBalancing
+	}
+	return 0
+}
+
+func (m *ClientStats) GetNumCallsFinishedWithClientFailedToSend() int64 {
+	if m != nil {
+		return m.NumCallsFinishedWithClientFailedToSend
+	}
+	return 0
+}
+
+func (m *ClientStats) GetNumCallsFinishedKnownReceived() int64 {
+	if m != nil {
+		return m.NumCallsFinishedKnownReceived
+	}
+	return 0
+}
+
+type LoadBalanceResponse struct {
+	// Types that are valid to be assigned to LoadBalanceResponseType:
+	//	*LoadBalanceResponse_InitialResponse
+	//	*LoadBalanceResponse_ServerList
+	LoadBalanceResponseType isLoadBalanceResponse_LoadBalanceResponseType `protobuf_oneof:"load_balance_response_type"`
+}
+
+func (m *LoadBalanceResponse) Reset()                    { *m = LoadBalanceResponse{} }
+func (m *LoadBalanceResponse) String() string            { return proto.CompactTextString(m) }
+func (*LoadBalanceResponse) ProtoMessage()               {}
+func (*LoadBalanceResponse) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{5} }
+
+type isLoadBalanceResponse_LoadBalanceResponseType interface {
+	isLoadBalanceResponse_LoadBalanceResponseType()
+}
+
+type LoadBalanceResponse_InitialResponse struct {
+	InitialResponse *InitialLoadBalanceResponse `protobuf:"bytes,1,opt,name=initial_response,json=initialResponse,oneof"`
+}
+type LoadBalanceResponse_ServerList struct {
+	ServerList *ServerList `protobuf:"bytes,2,opt,name=server_list,json=serverList,oneof"`
+}
+
+func (*LoadBalanceResponse_InitialResponse) isLoadBalanceResponse_LoadBalanceResponseType() {}
+func (*LoadBalanceResponse_ServerList) isLoadBalanceResponse_LoadBalanceResponseType()      {}
+
+func (m *LoadBalanceResponse) GetLoadBalanceResponseType() isLoadBalanceResponse_LoadBalanceResponseType {
+	if m != nil {
+		return m.LoadBalanceResponseType
+	}
+	return nil
+}
+
+func (m *LoadBalanceResponse) GetInitialResponse() *InitialLoadBalanceResponse {
+	if x, ok := m.GetLoadBalanceResponseType().(*LoadBalanceResponse_InitialResponse); ok {
+		return x.InitialResponse
+	}
+	return nil
+}
+
+func (m *LoadBalanceResponse) GetServerList() *ServerList {
+	if x, ok := m.GetLoadBalanceResponseType().(*LoadBalanceResponse_ServerList); ok {
+		return x.ServerList
+	}
+	return nil
+}
+
+// XXX_OneofFuncs is for the internal use of the proto package.
+func (*LoadBalanceResponse) XXX_OneofFuncs() (func(msg proto.Message, b *proto.Buffer) error, func(msg proto.Message, tag, wire int, b *proto.Buffer) (bool, error), func(msg proto.Message) (n int), []interface{}) {
+	return _LoadBalanceResponse_OneofMarshaler, _LoadBalanceResponse_OneofUnmarshaler, _LoadBalanceResponse_OneofSizer, []interface{}{
+		(*LoadBalanceResponse_InitialResponse)(nil),
+		(*LoadBalanceResponse_ServerList)(nil),
+	}
+}
+
+func _LoadBalanceResponse_OneofMarshaler(msg proto.Message, b *proto.Buffer) error {
+	m := msg.(*LoadBalanceResponse)
+	// load_balance_response_type
+	switch x := m.LoadBalanceResponseType.(type) {
+	case *LoadBalanceResponse_InitialResponse:
+		b.EncodeVarint(1<<3 | proto.WireBytes)
+		if err := b.EncodeMessage(x.InitialResponse); err != nil {
+			return err
+		}
+	case *LoadBalanceResponse_ServerList:
+		b.EncodeVarint(2<<3 | proto.WireBytes)
+		if err := b.EncodeMessage(x.ServerList); err != nil {
+			return err
+		}
+	case nil:
+	default:
+		return fmt.Errorf("LoadBalanceResponse.LoadBalanceResponseType has unexpected type %T", x)
+	}
+	return nil
+}
+
+func _LoadBalanceResponse_OneofUnmarshaler(msg proto.Message, tag, wire int, b *proto.Buffer) (bool, error) {
+	m := msg.(*LoadBalanceResponse)
+	switch tag {
+	case 1: // load_balance_response_type.initial_response
+		if wire != proto.WireBytes {
+			return true, proto.ErrInternalBadWireType
+		}
+		msg := new(InitialLoadBalanceResponse)
+		err := b.DecodeMessage(msg)
+		m.LoadBalanceResponseType = &LoadBalanceResponse_InitialResponse{msg}
+		return true, err
+	case 2: // load_balance_response_type.server_list
+		if wire != proto.WireBytes {
+			return true, proto.ErrInternalBadWireType
+		}
+		msg := new(ServerList)
+		err := b.DecodeMessage(msg)
+		m.LoadBalanceResponseType = &LoadBalanceResponse_ServerList{msg}
+		return true, err
+	default:
+		return false, nil
+	}
+}
+
+func _LoadBalanceResponse_OneofSizer(msg proto.Message) (n int) {
+	m := msg.(*LoadBalanceResponse)
+	// load_balance_response_type
+	switch x := m.LoadBalanceResponseType.(type) {
+	case *LoadBalanceResponse_InitialResponse:
+		s := proto.Size(x.InitialResponse)
+		n += proto.SizeVarint(1<<3 | proto.WireBytes)
+		n += proto.SizeVarint(uint64(s))
+		n += s
+	case *LoadBalanceResponse_ServerList:
+		s := proto.Size(x.ServerList)
+		n += proto.SizeVarint(2<<3 | proto.WireBytes)
+		n += proto.SizeVarint(uint64(s))
+		n += s
+	case nil:
+	default:
+		panic(fmt.Sprintf("proto: unexpected type %T in oneof", x))
+	}
+	return n
+}
+
+type InitialLoadBalanceResponse struct {
+	// This is an application layer redirect that indicates the client should use
+	// the specified server for load balancing. When this field is non-empty in
+	// the response, the client should open a separate connection to the
+	// load_balancer_delegate and call the BalanceLoad method. Its length should
+	// be less than 64 bytes.
+	LoadBalancerDelegate string `protobuf:"bytes,1,opt,name=load_balancer_delegate,json=loadBalancerDelegate" json:"load_balancer_delegate,omitempty"`
+	// This interval defines how often the client should send the client stats
+	// to the load balancer. Stats should only be reported when the duration is
+	// positive.
+	ClientStatsReportInterval *Duration `protobuf:"bytes,2,opt,name=client_stats_report_interval,json=clientStatsReportInterval" json:"client_stats_report_interval,omitempty"`
+}
+
+func (m *InitialLoadBalanceResponse) Reset()                    { *m = InitialLoadBalanceResponse{} }
+func (m *InitialLoadBalanceResponse) String() string            { return proto.CompactTextString(m) }
+func (*InitialLoadBalanceResponse) ProtoMessage()               {}
+func (*InitialLoadBalanceResponse) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{6} }
+
+func (m *InitialLoadBalanceResponse) GetLoadBalancerDelegate() string {
+	if m != nil {
+		return m.LoadBalancerDelegate
+	}
+	return ""
+}
+
+func (m *InitialLoadBalanceResponse) GetClientStatsReportInterval() *Duration {
+	if m != nil {
+		return m.ClientStatsReportInterval
+	}
+	return nil
+}
+
+type ServerList struct {
+	// Contains a list of servers selected by the load balancer. The list will
+	// be updated when server resolutions change or as needed to balance load
+	// across more servers. The client should consume the server list in order
+	// unless instructed otherwise via the client_config.
+	Servers []*Server `protobuf:"bytes,1,rep,name=servers" json:"servers,omitempty"`
+	// Indicates the amount of time that the client should consider this server
+	// list as valid. It may be considered stale after waiting this interval of
+	// time after receiving the list. If the interval is not positive, the
+	// client can assume the list is valid until the next list is received.
+	ExpirationInterval *Duration `protobuf:"bytes,3,opt,name=expiration_interval,json=expirationInterval" json:"expiration_interval,omitempty"`
+}
+
+func (m *ServerList) Reset()                    { *m = ServerList{} }
+func (m *ServerList) String() string            { return proto.CompactTextString(m) }
+func (*ServerList) ProtoMessage()               {}
+func (*ServerList) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{7} }
+
+func (m *ServerList) GetServers() []*Server {
+	if m != nil {
+		return m.Servers
+	}
+	return nil
+}
+
+func (m *ServerList) GetExpirationInterval() *Duration {
+	if m != nil {
+		return m.ExpirationInterval
+	}
+	return nil
+}
+
+// Contains server information. When none of the [drop_for_*] fields are true,
+// use the other fields. When drop_for_rate_limiting is true, ignore all other
+// fields. Use drop_for_load_balancing only when it is true and
+// drop_for_rate_limiting is false.
+type Server struct {
+	// A resolved address for the server, serialized in network-byte-order. It may
+	// either be an IPv4 or IPv6 address.
+	IpAddress []byte `protobuf:"bytes,1,opt,name=ip_address,json=ipAddress,proto3" json:"ip_address,omitempty"`
+	// A resolved port number for the server.
+	Port int32 `protobuf:"varint,2,opt,name=port" json:"port,omitempty"`
+	// An opaque but printable token given to the frontend for each pick. All
+	// frontend requests for that pick must include the token in its initial
+	// metadata. The token is used by the backend to verify the request and to
+	// allow the backend to report load to the gRPC LB system.
+	//
+	// Its length is variable but less than 50 bytes.
+	LoadBalanceToken string `protobuf:"bytes,3,opt,name=load_balance_token,json=loadBalanceToken" json:"load_balance_token,omitempty"`
+	// Indicates whether this particular request should be dropped by the client
+	// for rate limiting.
+	DropForRateLimiting bool `protobuf:"varint,4,opt,name=drop_for_rate_limiting,json=dropForRateLimiting" json:"drop_for_rate_limiting,omitempty"`
+	// Indicates whether this particular request should be dropped by the client
+	// for load balancing.
+	DropForLoadBalancing bool `protobuf:"varint,5,opt,name=drop_for_load_balancing,json=dropForLoadBalancing" json:"drop_for_load_balancing,omitempty"`
+}
+
+func (m *Server) Reset()                    { *m = Server{} }
+func (m *Server) String() string            { return proto.CompactTextString(m) }
+func (*Server) ProtoMessage()               {}
+func (*Server) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{8} }
+
+func (m *Server) GetIpAddress() []byte {
+	if m != nil {
+		return m.IpAddress
+	}
+	return nil
+}
+
+func (m *Server) GetPort() int32 {
+	if m != nil {
+		return m.Port
+	}
+	return 0
+}
+
+func (m *Server) GetLoadBalanceToken() string {
+	if m != nil {
+		return m.LoadBalanceToken
+	}
+	return ""
+}
+
+func (m *Server) GetDropForRateLimiting() bool {
+	if m != nil {
+		return m.DropForRateLimiting
+	}
+	return false
+}
+
+func (m *Server) GetDropForLoadBalancing() bool {
+	if m != nil {
+		return m.DropForLoadBalancing
+	}
+	return false
+}
+
+func init() {
+	proto.RegisterType((*Duration)(nil), "grpc.lb.v1.Duration")
+	proto.RegisterType((*Timestamp)(nil), "grpc.lb.v1.Timestamp")
+	proto.RegisterType((*LoadBalanceRequest)(nil), "grpc.lb.v1.LoadBalanceRequest")
+	proto.RegisterType((*InitialLoadBalanceRequest)(nil), "grpc.lb.v1.InitialLoadBalanceRequest")
+	proto.RegisterType((*ClientStats)(nil), "grpc.lb.v1.ClientStats")
+	proto.RegisterType((*LoadBalanceResponse)(nil), "grpc.lb.v1.LoadBalanceResponse")
+	proto.RegisterType((*InitialLoadBalanceResponse)(nil), "grpc.lb.v1.InitialLoadBalanceResponse")
+	proto.RegisterType((*ServerList)(nil), "grpc.lb.v1.ServerList")
+	proto.RegisterType((*Server)(nil), "grpc.lb.v1.Server")
+}
+
+func init() { proto.RegisterFile("grpclb.proto", fileDescriptor0) }
+
+var fileDescriptor0 = []byte{
+	// 733 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x94, 0x55, 0xdd, 0x4e, 0x1b, 0x39,
+	0x14, 0x66, 0x36, 0xfc, 0xe5, 0x24, 0x5a, 0x58, 0x93, 0x85, 0xc0, 0xc2, 0x2e, 0x1b, 0xa9, 0x34,
+	0xaa, 0x68, 0x68, 0x43, 0x7b, 0xd1, 0x9f, 0x9b, 0x02, 0x45, 0x41, 0xe5, 0xa2, 0x72, 0xa8, 0x7a,
+	0x55, 0x59, 0x4e, 0xc6, 0x80, 0xc5, 0xc4, 0x9e, 0xda, 0x4e, 0x68, 0x2f, 0x7b, 0xd9, 0x47, 0xe9,
+	0x63, 0x54, 0x7d, 0x86, 0xbe, 0x4f, 0x65, 0x7b, 0x26, 0x33, 0x90, 0x1f, 0xd4, 0xbb, 0xf1, 0xf1,
+	0x77, 0xbe, 0xf3, 0xf9, 0xd8, 0xdf, 0x19, 0x28, 0x5f, 0xa8, 0xb8, 0x1b, 0x75, 0x1a, 0xb1, 0x92,
+	0x46, 0x22, 0xb0, 0xab, 0x46, 0xd4, 0x69, 0x0c, 0x1e, 0xd7, 0x9e, 0xc3, 0xe2, 0x51, 0x5f, 0x51,
+	0xc3, 0xa5, 0x40, 0x55, 0x58, 0xd0, 0xac, 0x2b, 0x45, 0xa8, 0xab, 0xc1, 0x76, 0x50, 0x2f, 0xe0,
+	0x74, 0x89, 0x2a, 0x30, 0x27, 0xa8, 0x90, 0xba, 0xfa, 0xc7, 0x76, 0x50, 0x9f, 0xc3, 0x7e, 0x51,
+	0x7b, 0x01, 0xc5, 0x33, 0xde, 0x63, 0xda, 0xd0, 0x5e, 0xfc, 0xdb, 0xc9, 0xdf, 0x03, 0x40, 0xa7,
+	0x92, 0x86, 0x07, 0x34, 0xa2, 0xa2, 0xcb, 0x30, 0xfb, 0xd8, 0x67, 0xda, 0xa0, 0xb7, 0xb0, 0xc4,
+	0x05, 0x37, 0x9c, 0x46, 0x44, 0xf9, 0x90, 0xa3, 0x2b, 0x35, 0xef, 0x35, 0x32, 0xd5, 0x8d, 0x13,
+	0x0f, 0x19, 0xcd, 0x6f, 0xcd, 0xe0, 0x3f, 0x93, 0xfc, 0x94, 0xf1, 0x25, 0x94, 0xbb, 0x11, 0x67,
+	0xc2, 0x10, 0x6d, 0xa8, 0xf1, 0x2a, 0x4a, 0xcd, 0xb5, 0x3c, 0xdd, 0xa1, 0xdb, 0x6f, 0xdb, 0xed,
+	0xd6, 0x0c, 0x2e, 0x75, 0xb3, 0xe5, 0xc1, 0x3f, 0xb0, 0x1e, 0x49, 0x1a, 0x92, 0x8e, 0x2f, 0x93,
+	0x8a, 0x22, 0xe6, 0x73, 0xcc, 0x6a, 0x7b, 0xb0, 0x3e, 0x51, 0x09, 0x42, 0x30, 0x2b, 0x68, 0x8f,
+	0x39, 0xf9, 0x45, 0xec, 0xbe, 0x6b, 0x5f, 0x67, 0xa1, 0x94, 0x2b, 0x86, 0xf6, 0xa1, 0x68, 0xd2,
+	0x0e, 0x26, 0xe7, 0xfc, 0x3b, 0x2f, 0x6c, 0xd8, 0x5e, 0x9c, 0xe1, 0xd0, 0x03, 0xf8, 0x4b, 0xf4,
+	0x7b, 0xa4, 0x4b, 0xa3, 0x48, 0xdb, 0x33, 0x29, 0xc3, 0x42, 0x77, 0xaa, 0x02, 0x5e, 0x12, 0xfd,
+	0xde, 0xa1, 0x8d, 0xb7, 0x7d, 0x18, 0xed, 0x02, 0xca, 0xb0, 0xe7, 0x5c, 0x70, 0x7d, 0xc9, 0xc2,
+	0x6a, 0xc1, 0x81, 0x97, 0x53, 0xf0, 0x71, 0x12, 0x47, 0x04, 0x1a, 0xa3, 0x68, 0x72, 0xcd, 0xcd,
+	0x25, 0x09, 0x95, 0x8c, 0xc9, 0xb9, 0x54, 0x44, 0x51, 0xc3, 0x48, 0xc4, 0x7b, 0xdc, 0x70, 0x71,
+	0x51, 0x9d, 0x75, 0x4c, 0xf7, 0x6f, 0x33, 0xbd, 0xe7, 0xe6, 0xf2, 0x48, 0xc9, 0xf8, 0x58, 0x2a,
+	0x4c, 0x0d, 0x3b, 0x4d, 0xe0, 0x88, 0xc2, 0xde, 0x9d, 0x05, 0x72, 0xed, 0xb6, 0x15, 0xe6, 0x5c,
+	0x85, 0xfa, 0x94, 0x0a, 0x59, 0xef, 0x6d, 0x89, 0x0f, 0xf0, 0x70, 0x52, 0x89, 0xe4, 0x19, 0x9c,
+	0x53, 0x1e, 0xb1, 0x90, 0x18, 0x49, 0x34, 0x13, 0x61, 0x75, 0xde, 0x15, 0xd8, 0x19, 0x57, 0xc0,
+	0x5f, 0xd5, 0xb1, 0xc3, 0x9f, 0xc9, 0x36, 0x13, 0x21, 0x6a, 0xc1, 0xff, 0x63, 0xe8, 0xaf, 0x84,
+	0xbc, 0x16, 0x44, 0xb1, 0x2e, 0xe3, 0x03, 0x16, 0x56, 0x17, 0x1c, 0xe5, 0xd6, 0x6d, 0xca, 0x37,
+	0x16, 0x85, 0x13, 0x50, 0xed, 0x47, 0x00, 0x2b, 0x37, 0x9e, 0x8d, 0x8e, 0xa5, 0xd0, 0x0c, 0xb5,
+	0x61, 0x39, 0x73, 0x80, 0x8f, 0x25, 0x4f, 0x63, 0xe7, 0x2e, 0x0b, 0x78, 0x74, 0x6b, 0x06, 0x2f,
+	0x0d, 0x3d, 0x90, 0x90, 0x3e, 0x83, 0x92, 0x66, 0x6a, 0xc0, 0x14, 0x89, 0xb8, 0x36, 0x89, 0x07,
+	0x56, 0xf3, 0x7c, 0x6d, 0xb7, 0x7d, 0xca, 0x9d, 0x87, 0x40, 0x0f, 0x57, 0x07, 0x9b, 0xb0, 0x71,
+	0xcb, 0x01, 0x9e, 0xd3, 0x5b, 0xe0, 0x5b, 0x00, 0x1b, 0x93, 0xa5, 0xa0, 0x27, 0xb0, 0x9a, 0x4f,
+	0x56, 0x24, 0x64, 0x11, 0xbb, 0xa0, 0x26, 0xb5, 0x45, 0x25, 0xca, 0x92, 0xd4, 0x51, 0xb2, 0x87,
+	0xde, 0xc1, 0x66, 0xde, 0xb2, 0x44, 0xb1, 0x58, 0x2a, 0x43, 0xb8, 0x30, 0x4c, 0x0d, 0x68, 0x94,
+	0xc8, 0xaf, 0xe4, 0xe5, 0xa7, 0x43, 0x0c, 0xaf, 0xe7, 0xdc, 0x8b, 0x5d, 0xde, 0x49, 0x92, 0x56,
+	0xfb, 0x12, 0x00, 0x64, 0xc7, 0x44, 0xbb, 0x76, 0x62, 0xd9, 0x95, 0x9d, 0x58, 0x85, 0x7a, 0xa9,
+	0x89, 0x46, 0xfb, 0x81, 0x53, 0x08, 0x7a, 0x0d, 0x2b, 0xec, 0x53, 0xcc, 0x7d, 0x95, 0x4c, 0x4a,
+	0x61, 0x8a, 0x14, 0x94, 0x25, 0x0c, 0x35, 0xfc, 0x0c, 0x60, 0xde, 0x53, 0xa3, 0x2d, 0x00, 0x1e,
+	0x13, 0x1a, 0x86, 0x8a, 0x69, 0x3f, 0x34, 0xcb, 0xb8, 0xc8, 0xe3, 0x57, 0x3e, 0x60, 0xe7, 0x87,
+	0x55, 0x9f, 0x4c, 0x4d, 0xf7, 0x6d, 0xed, 0x7c, 0xe3, 0x2e, 0x8c, 0xbc, 0x62, 0xc2, 0x69, 0x28,
+	0xe2, 0xe5, 0x5c, 0x2b, 0xcf, 0x6c, 0x1c, 0xed, 0xc3, 0xea, 0x14, 0xdb, 0x2e, 0xe2, 0x95, 0x70,
+	0x8c, 0x45, 0x9f, 0xc2, 0xda, 0x34, 0x2b, 0x2e, 0xe2, 0x4a, 0x38, 0xc6, 0x76, 0xcd, 0x0e, 0x94,
+	0x73, 0xf7, 0xaf, 0x10, 0x86, 0x52, 0xf2, 0x6d, 0xc3, 0xe8, 0xdf, 0x7c, 0x83, 0x46, 0x87, 0xe5,
+	0xc6, 0x7f, 0x13, 0xf7, 0xfd, 0x43, 0xaa, 0x07, 0x8f, 0x82, 0xce, 0xbc, 0xfb, 0x7d, 0xed, 0xff,
+	0x0a, 0x00, 0x00, 0xff, 0xff, 0x64, 0xbf, 0xda, 0x5e, 0xce, 0x06, 0x00, 0x00,
+}

vendor/google.golang.org/grpc/grpclb/grpc_lb_v1/grpclb.proto

@@ -0,0 +1,179 @@
+// Copyright 2016, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+syntax = "proto3";
+
+package grpc.lb.v1;
+
+message Duration {
+  // Signed seconds of the span of time. Must be from -315,576,000,000
+  // to +315,576,000,000 inclusive.
+  int64 seconds = 1;
+
+  // Signed fractions of a second at nanosecond resolution of the span
+  // of time. Durations less than one second are represented with a 0
+  // `seconds` field and a positive or negative `nanos` field. For durations
+  // of one second or more, a non-zero value for the `nanos` field must be
+  // of the same sign as the `seconds` field. Must be from -999,999,999
+  // to +999,999,999 inclusive.
+  int32 nanos = 2;
+}
+
+message Timestamp {
+
+  // Represents seconds of UTC time since Unix epoch
+  // 1970-01-01T00:00:00Z. Must be from 0001-01-01T00:00:00Z to
+  // 9999-12-31T23:59:59Z inclusive.
+  int64 seconds = 1;
+
+  // Non-negative fractions of a second at nanosecond resolution. Negative
+  // second values with fractions must still have non-negative nanos values
+  // that count forward in time. Must be from 0 to 999,999,999
+  // inclusive.
+  int32 nanos = 2;
+}
+
+service LoadBalancer {
+  // Bidirectional rpc to get a list of servers.
+  rpc BalanceLoad(stream LoadBalanceRequest)
+      returns (stream LoadBalanceResponse);
+}
+
+message LoadBalanceRequest {
+  oneof load_balance_request_type {
+    // This message should be sent on the first request to the load balancer.
+    InitialLoadBalanceRequest initial_request = 1;
+
+    // The client stats should be periodically reported to the load balancer
+    // based on the duration defined in the InitialLoadBalanceResponse.
+    ClientStats client_stats = 2;
+  }
+}
+
+message InitialLoadBalanceRequest {
+  // Name of load balanced service (IE, balancer.service.com)
+  // length should be less than 256 bytes.
+  string name = 1;
+}
+
+// Contains client level statistics that are useful to load balancing. Each
+// count except the timestamp should be reset to zero after reporting the stats.
+message ClientStats {
+  // The timestamp of generating the report.
+  Timestamp timestamp = 1;
+
+  // The total number of RPCs that started.
+  int64 num_calls_started = 2;
+
+  // The total number of RPCs that finished.
+  int64 num_calls_finished = 3;
+
+  // The total number of RPCs that were dropped by the client because of rate
+  // limiting.
+  int64 num_calls_finished_with_drop_for_rate_limiting = 4;
+
+  // The total number of RPCs that were dropped by the client because of load
+  // balancing.
+  int64 num_calls_finished_with_drop_for_load_balancing = 5;
+
+  // The total number of RPCs that failed to reach a server except dropped RPCs.
+  int64 num_calls_finished_with_client_failed_to_send = 6;
+
+  // The total number of RPCs that finished and are known to have been received
+  // by a server.
+  int64 num_calls_finished_known_received = 7;
+}
+
+message LoadBalanceResponse {
+  oneof load_balance_response_type {
+    // This message should be sent on the first response to the client.
+    InitialLoadBalanceResponse initial_response = 1;
+
+    // Contains the list of servers selected by the load balancer. The client
+    // should send requests to these servers in the specified order.
+    ServerList server_list = 2;
+  }
+}
+
+message InitialLoadBalanceResponse {
+  // This is an application layer redirect that indicates the client should use
+  // the specified server for load balancing. When this field is non-empty in
+  // the response, the client should open a separate connection to the
+  // load_balancer_delegate and call the BalanceLoad method. Its length should
+  // be less than 64 bytes.
+  string load_balancer_delegate = 1;
+
+  // This interval defines how often the client should send the client stats
+  // to the load balancer. Stats should only be reported when the duration is
+  // positive.
+  Duration client_stats_report_interval = 2;
+}
+
+message ServerList {
+  // Contains a list of servers selected by the load balancer. The list will
+  // be updated when server resolutions change or as needed to balance load
+  // across more servers. The client should consume the server list in order
+  // unless instructed otherwise via the client_config.
+  repeated Server servers = 1;
+
+  // Indicates the amount of time that the client should consider this server
+  // list as valid. It may be considered stale after waiting this interval of
+  // time after receiving the list. If the interval is not positive, the
+  // client can assume the list is valid until the next list is received.
+  Duration expiration_interval = 3;
+}
+
+// Contains server information. When none of the [drop_for_*] fields are true,
+// use the other fields. When drop_for_rate_limiting is true, ignore all other
+// fields. Use drop_for_load_balancing only when it is true and
+// drop_for_rate_limiting is false.
+message Server {
+  // A resolved address for the server, serialized in network-byte-order. It may
+  // either be an IPv4 or IPv6 address.
+  bytes ip_address = 1;
+
+  // A resolved port number for the server.
+  int32 port = 2;
+
+  // An opaque but printable token given to the frontend for each pick. All
+  // frontend requests for that pick must include the token in its initial
+  // metadata. The token is used by the backend to verify the request and to
+  // allow the backend to report load to the gRPC LB system.
+  //
+  // Its length is variable but less than 50 bytes.
+  string load_balance_token = 3;
+
+  // Indicates whether this particular request should be dropped by the client
+  // for rate limiting.
+  bool drop_for_rate_limiting = 4;
+
+  // Indicates whether this particular request should be dropped by the client
+  // for load balancing.
+  bool drop_for_load_balancing = 5;
+}

vendor/google.golang.org/grpc/interceptor.go

@@ -40,7 +40,7 @@ import (
 // UnaryInvoker is called by UnaryClientInterceptor to complete RPCs.
 type UnaryInvoker func(ctx context.Context, method string, req, reply interface{}, cc *ClientConn, opts ...CallOption) error
 
-// UnaryClientInterceptor intercepts the execution of a unary RPC on the client. inovker is the handler to complete the RPC
+// UnaryClientInterceptor intercepts the execution of a unary RPC on the client. invoker is the handler to complete the RPC
 // and it is the responsibility of the interceptor to call it.
 // This is the EXPERIMENTAL API.
 type UnaryClientInterceptor func(ctx context.Context, method string, req, reply interface{}, cc *ClientConn, invoker UnaryInvoker, opts ...CallOption) error

vendor/google.golang.org/grpc/keepalive/keepalive.go

@@ -0,0 +1,80 @@
+/*
+ *
+ * Copyright 2017, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+// Package keepalive defines configurable parameters for point-to-point healthcheck.
+package keepalive
+
+import (
+	"time"
+)
+
+// ClientParameters is used to set keepalive parameters on the client-side.
+// These configure how the client will actively probe to notice when a connection broken
+// and to cause activity so intermediaries are aware the connection is still in use.
+// Make sure these parameters are set in coordination with the keepalive policy on the server,
+// as incompatible settings can result in closing of connection.
+type ClientParameters struct {
+	// After a duration of this time if the client doesn't see any activity it pings the server to see if the transport is still alive.
+	Time time.Duration // The current default value is infinity.
+	// After having pinged for keepalive check, the client waits for a duration of Timeout and if no activity is seen even after that
+	// the connection is closed.
+	Timeout time.Duration // The current default value is 20 seconds.
+	// If true, client runs keepalive checks even with no active RPCs.
+	PermitWithoutStream bool // false by default.
+}
+
+// ServerParameters is used to set keepalive and max-age parameters on the server-side.
+type ServerParameters struct {
+	// MaxConnectionIdle is a duration for the amount of time after which an idle connection would be closed by sending a GoAway.
+	// Idleness duration is defined since the most recent time the number of outstanding RPCs became zero or the connection establishment.
+	MaxConnectionIdle time.Duration // The current default value is infinity.
+	// MaxConnectionAge is a duration for the maximum amount of time a connection may exist before it will be closed by sending a GoAway.
+	// A random jitter of +/-10% will be added to MaxConnectionAge to spread out connection storms.
+	MaxConnectionAge time.Duration // The current default value is infinity.
+	// MaxConnectinoAgeGrace is an additive period after MaxConnectionAge after which the connection will be forcibly closed.
+	MaxConnectionAgeGrace time.Duration // The current default value is infinity.
+	// After a duration of this time if the server doesn't see any activity it pings the client to see if the transport is still alive.
+	Time time.Duration // The current default value is 2 hours.
+	// After having pinged for keepalive check, the server waits for a duration of Timeout and if no activity is seen even after that
+	// the connection is closed.
+	Timeout time.Duration // The current default value is 20 seconds.
+}
+
+// EnforcementPolicy is used to set keepalive enforcement policy on the server-side.
+// Server will close connection with a client that violates this policy.
+type EnforcementPolicy struct {
+	// MinTime is the minimum amount of time a client should wait before sending a keepalive ping.
+	MinTime time.Duration // The current default value is 5 minutes.
+	// If true, server expects keepalive pings even when there are no active streams(RPCs).
+	PermitWithoutStream bool // false by default.
+}

vendor/google.golang.org/grpc/metadata/metadata.go

@@ -32,49 +32,19 @@
  */
 
 // Package metadata define the structure of the metadata supported by gRPC library.
+// Please refer to http://www.grpc.io/docs/guides/wire.html for more information about custom-metadata.
 package metadata // import "google.golang.org/grpc/metadata"
 
 import (
-	"encoding/base64"
 	"fmt"
 	"strings"
 
 	"golang.org/x/net/context"
 )
 
-const (
+// DecodeKeyValue returns k, v, nil.  It is deprecated and should not be used.
-	binHdrSuffix = "-bin"
-)
-
-// encodeKeyValue encodes key and value qualified for transmission via gRPC.
-// Transmitting binary headers violates HTTP/2 spec.
-// TODO(zhaoq): Maybe check if k is ASCII also.
-func encodeKeyValue(k, v string) (string, string) {
-	k = strings.ToLower(k)
-	if strings.HasSuffix(k, binHdrSuffix) {
-		val := base64.StdEncoding.EncodeToString([]byte(v))
-		v = string(val)
-	}
-	return k, v
-}
-
-// DecodeKeyValue returns the original key and value corresponding to the
-// encoded data in k, v.
-// If k is a binary header and v contains comma, v is split on comma before decoded,
-// and the decoded v will be joined with comma before returned.
 func DecodeKeyValue(k, v string) (string, string, error) {
-	if !strings.HasSuffix(k, binHdrSuffix) {
 	return k, v, nil
-	}
-	vvs := strings.Split(v, ",")
-	for i, vv := range vvs {
-		val, err := base64.StdEncoding.DecodeString(vv)
-		if err != nil {
-			return "", "", err
-		}
-		vvs[i] = string(val)
-	}
-	return k, strings.Join(vvs, ","), nil
 }
 
 // MD is a mapping from metadata keys to values. Users should use the following
@@ -82,10 +52,11 @@ func DecodeKeyValue(k, v string) (string, string, error) {
 type MD map[string][]string
 
 // New creates a MD from given key-value map.
+// Keys are automatically converted to lowercase.
 func New(m map[string]string) MD {
 	md := MD{}
-	for k, v := range m {
+	for k, val := range m {
-		key, val := encodeKeyValue(k, v)
+		key := strings.ToLower(k)
 		md[key] = append(md[key], val)
 	}
 	return md
@@ -93,19 +64,19 @@ func New(m map[string]string) MD {
 
 // Pairs returns an MD formed by the mapping of key, value ...
 // Pairs panics if len(kv) is odd.
+// Keys are automatically converted to lowercase.
 func Pairs(kv ...string) MD {
 	if len(kv)%2 == 1 {
 		panic(fmt.Sprintf("metadata: Pairs got the odd number of input pairs for metadata: %d", len(kv)))
 	}
 	md := MD{}
-	var k string
+	var key string
 	for i, s := range kv {
 		if i%2 == 0 {
-			k = s
+			key = strings.ToLower(s)
 			continue
 		}
-		key, val := encodeKeyValue(k, s)
+		md[key] = append(md[key], s)
-		md[key] = append(md[key], val)
 	}
 	return md
 }
@@ -133,15 +104,41 @@ func Join(mds ...MD) MD {
 	return out
 }
 
-type mdKey struct{}
+type mdIncomingKey struct{}
+type mdOutgoingKey struct{}
 
-// NewContext creates a new context with md attached.
+// NewContext is a wrapper for NewOutgoingContext(ctx, md).  Deprecated.
 func NewContext(ctx context.Context, md MD) context.Context {
-	return context.WithValue(ctx, mdKey{}, md)
+	return NewOutgoingContext(ctx, md)
 }
 
-// FromContext returns the MD in ctx if it exists.
+// NewIncomingContext creates a new context with incoming md attached.
+func NewIncomingContext(ctx context.Context, md MD) context.Context {
+	return context.WithValue(ctx, mdIncomingKey{}, md)
+}
+
+// NewOutgoingContext creates a new context with outgoing md attached.
+func NewOutgoingContext(ctx context.Context, md MD) context.Context {
+	return context.WithValue(ctx, mdOutgoingKey{}, md)
+}
+
+// FromContext is a wrapper for FromIncomingContext(ctx).  Deprecated.
 func FromContext(ctx context.Context) (md MD, ok bool) {
-	md, ok = ctx.Value(mdKey{}).(MD)
+	return FromIncomingContext(ctx)
+}
+
+// FromIncomingContext returns the incoming MD in ctx if it exists.  The
+// returned md should be immutable, writing to it may cause races.
+// Modification should be made to the copies of the returned md.
+func FromIncomingContext(ctx context.Context) (md MD, ok bool) {
+	md, ok = ctx.Value(mdIncomingKey{}).(MD)
+	return
+}
+
+// FromOutgoingContext returns the outgoing MD in ctx if it exists.  The
+// returned md should be immutable, writing to it may cause races.
+// Modification should be made to the copies of the returned md.
+func FromOutgoingContext(ctx context.Context) (md MD, ok bool) {
+	md, ok = ctx.Value(mdOutgoingKey{}).(MD)
 	return
 }

vendor/google.golang.org/grpc/proxy.go

@@ -0,0 +1,145 @@
+/*
+ *
+ * Copyright 2017, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+package grpc
+
+import (
+	"bufio"
+	"errors"
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+	"net/http/httputil"
+	"net/url"
+
+	"golang.org/x/net/context"
+)
+
+var (
+	// errDisabled indicates that proxy is disabled for the address.
+	errDisabled = errors.New("proxy is disabled for the address")
+	// The following variable will be overwritten in the tests.
+	httpProxyFromEnvironment = http.ProxyFromEnvironment
+)
+
+func mapAddress(ctx context.Context, address string) (string, error) {
+	req := &http.Request{
+		URL: &url.URL{
+			Scheme: "https",
+			Host:   address,
+		},
+	}
+	url, err := httpProxyFromEnvironment(req)
+	if err != nil {
+		return "", err
+	}
+	if url == nil {
+		return "", errDisabled
+	}
+	return url.Host, nil
+}
+
+// To read a response from a net.Conn, http.ReadResponse() takes a bufio.Reader.
+// It's possible that this reader reads more than what's need for the response and stores
+// those bytes in the buffer.
+// bufConn wraps the original net.Conn and the bufio.Reader to make sure we don't lose the
+// bytes in the buffer.
+type bufConn struct {
+	net.Conn
+	r io.Reader
+}
+
+func (c *bufConn) Read(b []byte) (int, error) {
+	return c.r.Read(b)
+}
+
+func doHTTPConnectHandshake(ctx context.Context, conn net.Conn, addr string) (_ net.Conn, err error) {
+	defer func() {
+		if err != nil {
+			conn.Close()
+		}
+	}()
+
+	req := (&http.Request{
+		Method: http.MethodConnect,
+		URL:    &url.URL{Host: addr},
+		Header: map[string][]string{"User-Agent": {grpcUA}},
+	})
+
+	if err := sendHTTPRequest(ctx, req, conn); err != nil {
+		return nil, fmt.Errorf("failed to write the HTTP request: %v", err)
+	}
+
+	r := bufio.NewReader(conn)
+	resp, err := http.ReadResponse(r, req)
+	if err != nil {
+		return nil, fmt.Errorf("reading server HTTP response: %v", err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		dump, err := httputil.DumpResponse(resp, true)
+		if err != nil {
+			return nil, fmt.Errorf("failed to do connect handshake, status code: %s", resp.Status)
+		}
+		return nil, fmt.Errorf("failed to do connect handshake, response: %q", dump)
+	}
+
+	return &bufConn{Conn: conn, r: r}, nil
+}
+
+// newProxyDialer returns a dialer that connects to proxy first if necessary.
+// The returned dialer checks if a proxy is necessary, dial to the proxy with the
+// provided dialer, does HTTP CONNECT handshake and returns the connection.
+func newProxyDialer(dialer func(context.Context, string) (net.Conn, error)) func(context.Context, string) (net.Conn, error) {
+	return func(ctx context.Context, addr string) (conn net.Conn, err error) {
+		var skipHandshake bool
+		newAddr, err := mapAddress(ctx, addr)
+		if err != nil {
+			if err != errDisabled {
+				return nil, err
+			}
+			skipHandshake = true
+			newAddr = addr
+		}
+
+		conn, err = dialer(ctx, newAddr)
+		if err != nil {
+			return
+		}
+		if !skipHandshake {
+			conn, err = doHTTPConnectHandshake(ctx, conn, addr)
+		}
+		return
+	}
+}

vendor/google.golang.org/grpc/rpc_util.go

@@ -37,45 +37,21 @@ import (
 	"bytes"
 	"compress/gzip"
 	"encoding/binary"
-	"fmt"
 	"io"
 	"io/ioutil"
 	"math"
 	"os"
+	"time"
 
-	"github.com/golang/protobuf/proto"
 	"golang.org/x/net/context"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/peer"
+	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
 	"google.golang.org/grpc/transport"
 )
 
-// Codec defines the interface gRPC uses to encode and decode messages.
-type Codec interface {
-	// Marshal returns the wire format of v.
-	Marshal(v interface{}) ([]byte, error)
-	// Unmarshal parses the wire format into v.
-	Unmarshal(data []byte, v interface{}) error
-	// String returns the name of the Codec implementation. The returned
-	// string will be used as part of content type in transmission.
-	String() string
-}
-
-// protoCodec is a Codec implementation with protobuf. It is the default codec for gRPC.
-type protoCodec struct{}
-
-func (protoCodec) Marshal(v interface{}) ([]byte, error) {
-	return proto.Marshal(v.(proto.Message))
-}
-
-func (protoCodec) Unmarshal(data []byte, v interface{}) error {
-	return proto.Unmarshal(data, v.(proto.Message))
-}
-
-func (protoCodec) String() string {
-	return "proto"
-}
-
 // Compressor defines the interface gRPC uses to compress a message.
 type Compressor interface {
 	// Do compresses p into w.
@@ -138,6 +114,7 @@ type callInfo struct {
 	failFast  bool
 	headerMD  metadata.MD
 	trailerMD metadata.MD
+	peer      *peer.Peer
 	traceInfo traceInfo // in trace.go
 }
 
@@ -181,12 +158,22 @@ func Trailer(md *metadata.MD) CallOption {
 	})
 }
 
+// Peer returns a CallOption that retrieves peer information for a
+// unary RPC.
+func Peer(peer *peer.Peer) CallOption {
+	return afterCall(func(c *callInfo) {
+		if c.peer != nil {
+			*peer = *c.peer
+		}
+	})
+}
+
 // FailFast configures the action to take when an RPC is attempted on broken
 // connections or unreachable servers. If failfast is true, the RPC will fail
 // immediately. Otherwise, the RPC client will block the call until a
 // connection is available (or the call is canceled or times out) and will retry
 // the call if it fails due to a transient error. Please refer to
-// https://github.com/grpc/grpc/blob/master/doc/fail_fast.md
+// https://github.com/grpc/grpc/blob/master/doc/fail_fast.md. Note: failFast is default to true.
 func FailFast(failFast bool) CallOption {
 	return beforeCall(func(c *callInfo) error {
 		c.failFast = failFast
@@ -255,9 +242,11 @@ func (p *parser) recvMsg(maxMsgSize int) (pf payloadFormat, msg []byte, err erro
 
 // encode serializes msg and prepends the message header. If msg is nil, it
 // generates the message header of 0 message length.
-func encode(c Codec, msg interface{}, cp Compressor, cbuf *bytes.Buffer) ([]byte, error) {
+func encode(c Codec, msg interface{}, cp Compressor, cbuf *bytes.Buffer, outPayload *stats.OutPayload) ([]byte, error) {
-	var b []byte
+	var (
-	var length uint
+		b      []byte
+		length uint
+	)
 	if msg != nil {
 		var err error
 		// TODO(zhaoq): optimize to reduce memory alloc and copying.
@@ -265,6 +254,12 @@ func encode(c Codec, msg interface{}, cp Compressor, cbuf *bytes.Buffer) ([]byte
 		if err != nil {
 			return nil, err
 		}
+		if outPayload != nil {
+			outPayload.Payload = msg
+			// TODO truncate large payload.
+			outPayload.Data = b
+			outPayload.Length = len(b)
+		}
 		if cp != nil {
 			if err := cp.Do(cbuf, b); err != nil {
 				return nil, err
@@ -295,6 +290,10 @@ func encode(c Codec, msg interface{}, cp Compressor, cbuf *bytes.Buffer) ([]byte
 	// Copy encoded msg to buf
 	copy(buf[5:], b)
 
+	if outPayload != nil {
+		outPayload.WireLength = len(buf)
+	}
+
 	return buf, nil
 }
 
@@ -311,11 +310,14 @@ func checkRecvPayload(pf payloadFormat, recvCompress string, dc Decompressor) er
 	return nil
 }
 
-func recv(p *parser, c Codec, s *transport.Stream, dc Decompressor, m interface{}, maxMsgSize int) error {
+func recv(p *parser, c Codec, s *transport.Stream, dc Decompressor, m interface{}, maxMsgSize int, inPayload *stats.InPayload) error {
 	pf, d, err := p.recvMsg(maxMsgSize)
 	if err != nil {
 		return err
 	}
+	if inPayload != nil {
+		inPayload.WireLength = len(d)
+	}
 	if err := checkRecvPayload(pf, s.RecvCompress(), dc); err != nil {
 		return err
 	}
@@ -333,91 +335,90 @@ func recv(p *parser, c Codec, s *transport.Stream, dc Decompressor, m interface{
 	if err := c.Unmarshal(d, m); err != nil {
 		return Errorf(codes.Internal, "grpc: failed to unmarshal the received message %v", err)
 	}
+	if inPayload != nil {
+		inPayload.RecvTime = time.Now()
+		inPayload.Payload = m
+		// TODO truncate large payload.
+		inPayload.Data = d
+		inPayload.Length = len(d)
+	}
 	return nil
 }
 
-// rpcError defines the status from an RPC.
+type rpcInfo struct {
-type rpcError struct {
+	bytesSent     bool
-	code codes.Code
+	bytesReceived bool
-	desc string
 }
 
-func (e *rpcError) Error() string {
+type rpcInfoContextKey struct{}
-	return fmt.Sprintf("rpc error: code = %d desc = %s", e.code, e.desc)
+
+func newContextWithRPCInfo(ctx context.Context) context.Context {
+	return context.WithValue(ctx, rpcInfoContextKey{}, &rpcInfo{})
+}
+
+func rpcInfoFromContext(ctx context.Context) (s *rpcInfo, ok bool) {
+	s, ok = ctx.Value(rpcInfoContextKey{}).(*rpcInfo)
+	return
+}
+
+func updateRPCInfoInContext(ctx context.Context, s rpcInfo) {
+	if ss, ok := rpcInfoFromContext(ctx); ok {
+		*ss = s
+	}
+	return
 }
 
 // Code returns the error code for err if it was produced by the rpc system.
 // Otherwise, it returns codes.Unknown.
+//
+// Deprecated; use status.FromError and Code method instead.
 func Code(err error) codes.Code {
-	if err == nil {
+	if s, ok := status.FromError(err); ok {
-		return codes.OK
+		return s.Code()
-	}
-	if e, ok := err.(*rpcError); ok {
-		return e.code
 	}
 	return codes.Unknown
 }
 
 // ErrorDesc returns the error description of err if it was produced by the rpc system.
 // Otherwise, it returns err.Error() or empty string when err is nil.
+//
+// Deprecated; use status.FromError and Message method instead.
 func ErrorDesc(err error) string {
-	if err == nil {
+	if s, ok := status.FromError(err); ok {
-		return ""
+		return s.Message()
-	}
-	if e, ok := err.(*rpcError); ok {
-		return e.desc
 	}
 	return err.Error()
 }
 
 // Errorf returns an error containing an error code and a description;
 // Errorf returns nil if c is OK.
+//
+// Deprecated; use status.Errorf instead.
 func Errorf(c codes.Code, format string, a ...interface{}) error {
-	if c == codes.OK {
+	return status.Errorf(c, format, a...)
-		return nil
-	}
-	return &rpcError{
-		code: c,
-		desc: fmt.Sprintf(format, a...),
-	}
 }
 
-// toRPCErr converts an error into a rpcError.
+// toRPCErr converts an error into an error from the status package.
 func toRPCErr(err error) error {
-	switch e := err.(type) {
+	if _, ok := status.FromError(err); ok {
-	case *rpcError:
 		return err
+	}
+	switch e := err.(type) {
 	case transport.StreamError:
-		return &rpcError{
+		return status.Error(e.Code, e.Desc)
-			code: e.Code,
-			desc: e.Desc,
-		}
 	case transport.ConnectionError:
-		return &rpcError{
+		return status.Error(codes.Internal, e.Desc)
-			code: codes.Internal,
-			desc: e.Desc,
-		}
 	default:
 		switch err {
 		case context.DeadlineExceeded:
-			return &rpcError{
+			return status.Error(codes.DeadlineExceeded, err.Error())
-				code: codes.DeadlineExceeded,
-				desc: err.Error(),
-			}
 		case context.Canceled:
-			return &rpcError{
+			return status.Error(codes.Canceled, err.Error())
-				code: codes.Canceled,
-				desc: err.Error(),
-			}
 		case ErrClientConnClosing:
-			return &rpcError{
+			return status.Error(codes.FailedPrecondition, err.Error())
-				code: codes.FailedPrecondition,
-				desc: err.Error(),
 		}
 	}
-
+	return status.Error(codes.Unknown, err.Error())
-	}
-	return Errorf(codes.Unknown, "%v", err)
 }
 
 // convertCode converts a standard Go error into its canonical code. Note that
@@ -448,6 +449,44 @@ func convertCode(err error) codes.Code {
 	return codes.Unknown
 }
 
+// MethodConfig defines the configuration recommended by the service providers for a
+// particular method.
+// This is EXPERIMENTAL and subject to change.
+type MethodConfig struct {
+	// WaitForReady indicates whether RPCs sent to this method should wait until
+	// the connection is ready by default (!failfast). The value specified via the
+	// gRPC client API will override the value set here.
+	WaitForReady bool
+	// Timeout is the default timeout for RPCs sent to this method. The actual
+	// deadline used will be the minimum of the value specified here and the value
+	// set by the application via the gRPC client API.  If either one is not set,
+	// then the other will be used.  If neither is set, then the RPC has no deadline.
+	Timeout time.Duration
+	// MaxReqSize is the maximum allowed payload size for an individual request in a
+	// stream (client->server) in bytes. The size which is measured is the serialized
+	// payload after per-message compression (but before stream compression) in bytes.
+	// The actual value used is the minumum of the value specified here and the value set
+	// by the application via the gRPC client API. If either one is not set, then the other
+	// will be used.  If neither is set, then the built-in default is used.
+	// TODO: support this.
+	MaxReqSize uint32
+	// MaxRespSize is the maximum allowed payload size for an individual response in a
+	// stream (server->client) in bytes.
+	// TODO: support this.
+	MaxRespSize uint32
+}
+
+// ServiceConfig is provided by the service provider and contains parameters for how
+// clients that connect to the service should behave.
+// This is EXPERIMENTAL and subject to change.
+type ServiceConfig struct {
+	// LB is the load balancer the service providers recommends. The balancer specified
+	// via grpc.WithBalancer will override this.
+	LB Balancer
+	// Methods contains a map for the methods in this service.
+	Methods map[string]MethodConfig
+}
+
 // SupportPackageIsVersion4 is referenced from generated protocol buffer files
 // to assert that that code is compatible with this version of the grpc package.
 //
@@ -455,3 +494,8 @@ func convertCode(err error) codes.Code {
 // requires a synchronised update of grpc-go and protoc-gen-go. This constant
 // should not be referenced from any other code.
 const SupportPackageIsVersion4 = true
+
+// Version is the current grpc version.
+const Version = "1.3.0"
+
+const grpcUA = "grpc-go/" + Version

vendor/google.golang.org/grpc/server.go

@@ -53,7 +53,11 @@ import (
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/grpclog"
 	"google.golang.org/grpc/internal"
+	"google.golang.org/grpc/keepalive"
 	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
+	"google.golang.org/grpc/tap"
 	"google.golang.org/grpc/transport"
 )
 
@@ -110,8 +114,13 @@ type options struct {
 	maxMsgSize           int
 	unaryInt             UnaryServerInterceptor
 	streamInt            StreamServerInterceptor
+	inTapHandle          tap.ServerInHandle
+	statsHandler         stats.Handler
 	maxConcurrentStreams uint32
 	useHandlerImpl       bool // use http.Handler-based server
+	unknownStreamDesc    *StreamDesc
+	keepaliveParams      keepalive.ServerParameters
+	keepalivePolicy      keepalive.EnforcementPolicy
 }
 
 var defaultMaxMsgSize = 1024 * 1024 * 4 // use 4MB as the default message size limit
@@ -119,6 +128,20 @@ var defaultMaxMsgSize = 1024 * 1024 * 4 // use 4MB as the default message size l
 // A ServerOption sets options.
 type ServerOption func(*options)
 
+// KeepaliveParams returns a ServerOption that sets keepalive and max-age parameters for the server.
+func KeepaliveParams(kp keepalive.ServerParameters) ServerOption {
+	return func(o *options) {
+		o.keepaliveParams = kp
+	}
+}
+
+// KeepaliveEnforcementPolicy returns a ServerOption that sets keepalive enforcement policy for the server.
+func KeepaliveEnforcementPolicy(kep keepalive.EnforcementPolicy) ServerOption {
+	return func(o *options) {
+		o.keepalivePolicy = kep
+	}
+}
+
 // CustomCodec returns a ServerOption that sets a codec for message marshaling and unmarshaling.
 func CustomCodec(codec Codec) ServerOption {
 	return func(o *options) {
@@ -186,6 +209,42 @@ func StreamInterceptor(i StreamServerInterceptor) ServerOption {
 	}
 }
 
+// InTapHandle returns a ServerOption that sets the tap handle for all the server
+// transport to be created. Only one can be installed.
+func InTapHandle(h tap.ServerInHandle) ServerOption {
+	return func(o *options) {
+		if o.inTapHandle != nil {
+			panic("The tap handle has been set.")
+		}
+		o.inTapHandle = h
+	}
+}
+
+// StatsHandler returns a ServerOption that sets the stats handler for the server.
+func StatsHandler(h stats.Handler) ServerOption {
+	return func(o *options) {
+		o.statsHandler = h
+	}
+}
+
+// UnknownServiceHandler returns a ServerOption that allows for adding a custom
+// unknown service handler. The provided method is a bidi-streaming RPC service
+// handler that will be invoked instead of returning the the "unimplemented" gRPC
+// error whenever a request is received for an unregistered service or method.
+// The handling function has full access to the Context of the request and the
+// stream, and the invocation passes through interceptors.
+func UnknownServiceHandler(streamHandler StreamHandler) ServerOption {
+	return func(o *options) {
+		o.unknownStreamDesc = &StreamDesc{
+			StreamName: "unknown_service_handler",
+			Handler:    streamHandler,
+			// We need to assume that the users of the streamHandler will want to use both.
+			ClientStreams: true,
+			ServerStreams: true,
+		}
+	}
+}
+
 // NewServer creates a gRPC server which has no service registered and has not
 // started to accept requests yet.
 func NewServer(opt ...ServerOption) *Server {
@@ -329,6 +388,7 @@ func (s *Server) useTransportAuthenticator(rawConn net.Conn) (net.Conn, credenti
 // read gRPC requests and then call the registered handlers to reply to them.
 // Serve returns when lis.Accept fails with fatal errors.  lis will be closed when
 // this method returns.
+// Serve always returns non-nil error.
 func (s *Server) Serve(lis net.Listener) error {
 	s.mu.Lock()
 	s.printf("serving")
@@ -412,17 +472,25 @@ func (s *Server) handleRawConn(rawConn net.Conn) {
 	if s.opts.useHandlerImpl {
 		s.serveUsingHandler(conn)
 	} else {
-		s.serveNewHTTP2Transport(conn, authInfo)
+		s.serveHTTP2Transport(conn, authInfo)
 	}
 }
 
-// serveNewHTTP2Transport sets up a new http/2 transport (using the
+// serveHTTP2Transport sets up a http/2 transport (using the
 // gRPC http2 server transport in transport/http2_server.go) and
 // serves streams on it.
 // This is run in its own goroutine (it does network I/O in
 // transport.NewServerTransport).
-func (s *Server) serveNewHTTP2Transport(c net.Conn, authInfo credentials.AuthInfo) {
+func (s *Server) serveHTTP2Transport(c net.Conn, authInfo credentials.AuthInfo) {
-	st, err := transport.NewServerTransport("http2", c, s.opts.maxConcurrentStreams, authInfo)
+	config := &transport.ServerConfig{
+		MaxStreams:      s.opts.maxConcurrentStreams,
+		AuthInfo:        authInfo,
+		InTapHandle:     s.opts.inTapHandle,
+		StatsHandler:    s.opts.statsHandler,
+		KeepaliveParams: s.opts.keepaliveParams,
+		KeepalivePolicy: s.opts.keepalivePolicy,
+	}
+	st, err := transport.NewServerTransport("http2", c, config)
 	if err != nil {
 		s.mu.Lock()
 		s.errorf("NewServerTransport(%q) failed: %v", c.RemoteAddr(), err)
@@ -448,6 +516,12 @@ func (s *Server) serveStreams(st transport.ServerTransport) {
 			defer wg.Done()
 			s.handleStream(st, stream, s.traceInfo(st, stream))
 		}()
+	}, func(ctx context.Context, method string) context.Context {
+		if !EnableTracing {
+			return ctx
+		}
+		tr := trace.New("grpc.Recv."+methodFamily(method), method)
+		return trace.NewContext(ctx, tr)
 	})
 	wg.Wait()
 }
@@ -497,15 +571,17 @@ func (s *Server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 // traceInfo returns a traceInfo and associates it with stream, if tracing is enabled.
 // If tracing is not enabled, it returns nil.
 func (s *Server) traceInfo(st transport.ServerTransport, stream *transport.Stream) (trInfo *traceInfo) {
-	if !EnableTracing {
+	tr, ok := trace.FromContext(stream.Context())
+	if !ok {
 		return nil
 	}
+
 	trInfo = &traceInfo{
-		tr: trace.New("grpc.Recv."+methodFamily(stream.Method()), stream.Method()),
+		tr: tr,
 	}
 	trInfo.firstLine.client = false
 	trInfo.firstLine.remoteAddr = st.RemoteAddr()
-	stream.TraceContext(trInfo.tr)
+
 	if dl, ok := stream.Context().Deadline(); ok {
 		trInfo.firstLine.deadline = dl.Sub(time.Now())
 	}
@@ -532,11 +608,17 @@ func (s *Server) removeConn(c io.Closer) {
 }
 
 func (s *Server) sendResponse(t transport.ServerTransport, stream *transport.Stream, msg interface{}, cp Compressor, opts *transport.Options) error {
-	var cbuf *bytes.Buffer
+	var (
+		cbuf       *bytes.Buffer
+		outPayload *stats.OutPayload
+	)
 	if cp != nil {
 		cbuf = new(bytes.Buffer)
 	}
-	p, err := encode(s.opts.codec, msg, cp, cbuf)
+	if s.opts.statsHandler != nil {
+		outPayload = &stats.OutPayload{}
+	}
+	p, err := encode(s.opts.codec, msg, cp, cbuf, outPayload)
 	if err != nil {
 		// This typically indicates a fatal issue (e.g., memory
 		// corruption or hardware faults) the application program
@@ -547,10 +629,33 @@ func (s *Server) sendResponse(t transport.ServerTransport, stream *transport.Str
 		// the optimal option.
 		grpclog.Fatalf("grpc: Server failed to encode response %v", err)
 	}
-	return t.Write(stream, p, opts)
+	err = t.Write(stream, p, opts)
+	if err == nil && outPayload != nil {
+		outPayload.SentTime = time.Now()
+		s.opts.statsHandler.HandleRPC(stream.Context(), outPayload)
+	}
+	return err
 }
 
 func (s *Server) processUnaryRPC(t transport.ServerTransport, stream *transport.Stream, srv *service, md *MethodDesc, trInfo *traceInfo) (err error) {
+	sh := s.opts.statsHandler
+	if sh != nil {
+		begin := &stats.Begin{
+			BeginTime: time.Now(),
+		}
+		sh.HandleRPC(stream.Context(), begin)
+	}
+	defer func() {
+		if sh != nil {
+			end := &stats.End{
+				EndTime: time.Now(),
+			}
+			if err != nil && err != io.EOF {
+				end.Error = toRPCErr(err)
+			}
+			sh.HandleRPC(stream.Context(), end)
+		}
+	}()
 	if trInfo != nil {
 		defer trInfo.tr.Finish()
 		trInfo.firstLine.client = false
@@ -567,7 +672,7 @@ func (s *Server) processUnaryRPC(t transport.ServerTransport, stream *transport.
 		stream.SetSendCompress(s.opts.cp.Type())
 	}
 	p := &parser{r: stream}
-	for {
+	for { // TODO: delete
 		pf, req, err := p.recvMsg(s.opts.maxMsgSize)
 		if err == io.EOF {
 			// The entire stream is done (for unary RPC only).
@@ -577,58 +682,68 @@ func (s *Server) processUnaryRPC(t transport.ServerTransport, stream *transport.
 			err = Errorf(codes.Internal, io.ErrUnexpectedEOF.Error())
 		}
 		if err != nil {
-			switch err := err.(type) {
+			if st, ok := status.FromError(err); ok {
-			case *rpcError:
+				if e := t.WriteStatus(stream, st); e != nil {
-				if err := t.WriteStatus(stream, err.code, err.desc); err != nil {
+					grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", e)
-					grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", err)
 				}
+			} else {
+				switch st := err.(type) {
 				case transport.ConnectionError:
 					// Nothing to do here.
 				case transport.StreamError:
-				if err := t.WriteStatus(stream, err.Code, err.Desc); err != nil {
+					if e := t.WriteStatus(stream, status.New(st.Code, st.Desc)); e != nil {
-					grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", err)
+						grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", e)
 					}
 				default:
-				panic(fmt.Sprintf("grpc: Unexpected error (%T) from recvMsg: %v", err, err))
+					panic(fmt.Sprintf("grpc: Unexpected error (%T) from recvMsg: %v", st, st))
+				}
 			}
 			return err
 		}
 
 		if err := checkRecvPayload(pf, stream.RecvCompress(), s.opts.dc); err != nil {
-			switch err := err.(type) {
+			if st, ok := status.FromError(err); ok {
-			case *rpcError:
+				if e := t.WriteStatus(stream, st); e != nil {
-				if err := t.WriteStatus(stream, err.code, err.desc); err != nil {
+					grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", e)
-					grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", err)
-				}
-			default:
-				if err := t.WriteStatus(stream, codes.Internal, err.Error()); err != nil {
-					grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", err)
-				}
-
 				}
 				return err
 			}
-		statusCode := codes.OK
+			if e := t.WriteStatus(stream, status.New(codes.Internal, err.Error())); e != nil {
-		statusDesc := ""
+				grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", e)
+			}
+
+			// TODO checkRecvPayload always return RPC error. Add a return here if necessary.
+		}
+		var inPayload *stats.InPayload
+		if sh != nil {
+			inPayload = &stats.InPayload{
+				RecvTime: time.Now(),
+			}
+		}
 		df := func(v interface{}) error {
+			if inPayload != nil {
+				inPayload.WireLength = len(req)
+			}
 			if pf == compressionMade {
 				var err error
 				req, err = s.opts.dc.Do(bytes.NewReader(req))
 				if err != nil {
-					if err := t.WriteStatus(stream, codes.Internal, err.Error()); err != nil {
+					return Errorf(codes.Internal, err.Error())
-						grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", err)
-					}
-					return err
 				}
 			}
 			if len(req) > s.opts.maxMsgSize {
 				// TODO: Revisit the error code. Currently keep it consistent with
 				// java implementation.
-				statusCode = codes.Internal
+				return status.Errorf(codes.Internal, "grpc: server received a message of %d bytes exceeding %d limit", len(req), s.opts.maxMsgSize)
-				statusDesc = fmt.Sprintf("grpc: server received a message of %d bytes exceeding %d limit", len(req), s.opts.maxMsgSize)
 			}
 			if err := s.opts.codec.Unmarshal(req, v); err != nil {
-				return err
+				return status.Errorf(codes.Internal, "grpc: error unmarshalling request: %v", err)
+			}
+			if inPayload != nil {
+				inPayload.Payload = v
+				inPayload.Data = req
+				inPayload.Length = len(req)
+				sh.HandleRPC(stream.Context(), inPayload)
 			}
 			if trInfo != nil {
 				trInfo.tr.LazyLog(&payload{sent: false, msg: v}, true)
@@ -637,22 +752,20 @@ func (s *Server) processUnaryRPC(t transport.ServerTransport, stream *transport.
 		}
 		reply, appErr := md.Handler(srv.server, stream.Context(), df, s.opts.unaryInt)
 		if appErr != nil {
-			if err, ok := appErr.(*rpcError); ok {
+			appStatus, ok := status.FromError(appErr)
-				statusCode = err.code
+			if !ok {
-				statusDesc = err.desc
+				// Convert appErr if it is not a grpc status error.
-			} else {
+				appErr = status.Error(convertCode(appErr), appErr.Error())
-				statusCode = convertCode(appErr)
+				appStatus, _ = status.FromError(appErr)
-				statusDesc = appErr.Error()
 			}
-			if trInfo != nil && statusCode != codes.OK {
+			if trInfo != nil {
-				trInfo.tr.LazyLog(stringer(statusDesc), true)
+				trInfo.tr.LazyLog(stringer(appStatus.Message()), true)
 				trInfo.tr.SetError()
 			}
-			if err := t.WriteStatus(stream, statusCode, statusDesc); err != nil {
+			if e := t.WriteStatus(stream, appStatus); e != nil {
-				grpclog.Printf("grpc: Server.processUnaryRPC failed to write status: %v", err)
+				grpclog.Printf("grpc: Server.processUnaryRPC failed to write status: %v", e)
-				return err
 			}
-			return nil
+			return appErr
 		}
 		if trInfo != nil {
 			trInfo.tr.LazyLog(stringer("OK"), false)
@@ -662,26 +775,57 @@ func (s *Server) processUnaryRPC(t transport.ServerTransport, stream *transport.
 			Delay: false,
 		}
 		if err := s.sendResponse(t, stream, reply, s.opts.cp, opts); err != nil {
-			switch err := err.(type) {
+			if err == io.EOF {
+				// The entire stream is done (for unary RPC only).
+				return err
+			}
+			if s, ok := status.FromError(err); ok {
+				if e := t.WriteStatus(stream, s); e != nil {
+					grpclog.Printf("grpc: Server.processUnaryRPC failed to write status: %v", e)
+				}
+			} else {
+				switch st := err.(type) {
 				case transport.ConnectionError:
 					// Nothing to do here.
 				case transport.StreamError:
-				statusCode = err.Code
+					if e := t.WriteStatus(stream, status.New(st.Code, st.Desc)); e != nil {
-				statusDesc = err.Desc
+						grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", e)
+					}
 				default:
-				statusCode = codes.Unknown
+					panic(fmt.Sprintf("grpc: Unexpected error (%T) from sendResponse: %v", st, st))
-				statusDesc = err.Error()
+				}
 			}
 			return err
 		}
 		if trInfo != nil {
 			trInfo.tr.LazyLog(&payload{sent: true, msg: reply}, true)
 		}
-		return t.WriteStatus(stream, statusCode, statusDesc)
+		// TODO: Should we be logging if writing status failed here, like above?
+		// Should the logging be in WriteStatus?  Should we ignore the WriteStatus
+		// error or allow the stats handler to see it?
+		return t.WriteStatus(stream, status.New(codes.OK, ""))
 	}
 }
 
 func (s *Server) processStreamingRPC(t transport.ServerTransport, stream *transport.Stream, srv *service, sd *StreamDesc, trInfo *traceInfo) (err error) {
+	sh := s.opts.statsHandler
+	if sh != nil {
+		begin := &stats.Begin{
+			BeginTime: time.Now(),
+		}
+		sh.HandleRPC(stream.Context(), begin)
+	}
+	defer func() {
+		if sh != nil {
+			end := &stats.End{
+				EndTime: time.Now(),
+			}
+			if err != nil && err != io.EOF {
+				end.Error = toRPCErr(err)
+			}
+			sh.HandleRPC(stream.Context(), end)
+		}
+	}()
 	if s.opts.cp != nil {
 		stream.SetSendCompress(s.opts.cp.Type())
 	}
@@ -694,6 +838,7 @@ func (s *Server) processStreamingRPC(t transport.ServerTransport, stream *transp
 		dc:           s.opts.dc,
 		maxMsgSize:   s.opts.maxMsgSize,
 		trInfo:       trInfo,
+		statsHandler: sh,
 	}
 	if ss.cp != nil {
 		ss.cbuf = new(bytes.Buffer)
@@ -712,39 +857,47 @@ func (s *Server) processStreamingRPC(t transport.ServerTransport, stream *transp
 		}()
 	}
 	var appErr error
+	var server interface{}
+	if srv != nil {
+		server = srv.server
+	}
 	if s.opts.streamInt == nil {
-		appErr = sd.Handler(srv.server, ss)
+		appErr = sd.Handler(server, ss)
 	} else {
 		info := &StreamServerInfo{
 			FullMethod:     stream.Method(),
 			IsClientStream: sd.ClientStreams,
 			IsServerStream: sd.ServerStreams,
 		}
-		appErr = s.opts.streamInt(srv.server, ss, info, sd.Handler)
+		appErr = s.opts.streamInt(server, ss, info, sd.Handler)
 	}
 	if appErr != nil {
-		if err, ok := appErr.(*rpcError); ok {
+		appStatus, ok := status.FromError(appErr)
-			ss.statusCode = err.code
+		if !ok {
-			ss.statusDesc = err.desc
+			switch err := appErr.(type) {
-		} else if err, ok := appErr.(transport.StreamError); ok {
+			case transport.StreamError:
-			ss.statusCode = err.Code
+				appStatus = status.New(err.Code, err.Desc)
-			ss.statusDesc = err.Desc
+			default:
-		} else {
+				appStatus = status.New(convertCode(appErr), appErr.Error())
-			ss.statusCode = convertCode(appErr)
-			ss.statusDesc = appErr.Error()
 			}
+			appErr = appStatus.Err()
 		}
 		if trInfo != nil {
 			ss.mu.Lock()
-		if ss.statusCode != codes.OK {
+			ss.trInfo.tr.LazyLog(stringer(appStatus.Message()), true)
-			ss.trInfo.tr.LazyLog(stringer(ss.statusDesc), true)
 			ss.trInfo.tr.SetError()
-		} else {
-			ss.trInfo.tr.LazyLog(stringer("OK"), false)
-		}
 			ss.mu.Unlock()
 		}
-	return t.WriteStatus(ss.s, ss.statusCode, ss.statusDesc)
+		t.WriteStatus(ss.s, appStatus)
+		// TODO: Should we log an error from WriteStatus here and below?
+		return appErr
+	}
+	if trInfo != nil {
+		ss.mu.Lock()
+		ss.trInfo.tr.LazyLog(stringer("OK"), false)
+		ss.mu.Unlock()
+	}
+	return t.WriteStatus(ss.s, status.New(codes.OK, ""))
 
 }
 
@@ -759,7 +912,8 @@ func (s *Server) handleStream(t transport.ServerTransport, stream *transport.Str
 			trInfo.tr.LazyLog(&fmtStringer{"Malformed method name %q", []interface{}{sm}}, true)
 			trInfo.tr.SetError()
 		}
-		if err := t.WriteStatus(stream, codes.InvalidArgument, fmt.Sprintf("malformed method name: %q", stream.Method())); err != nil {
+		errDesc := fmt.Sprintf("malformed method name: %q", stream.Method())
+		if err := t.WriteStatus(stream, status.New(codes.InvalidArgument, errDesc)); err != nil {
 			if trInfo != nil {
 				trInfo.tr.LazyLog(&fmtStringer{"%v", []interface{}{err}}, true)
 				trInfo.tr.SetError()
@@ -775,11 +929,16 @@ func (s *Server) handleStream(t transport.ServerTransport, stream *transport.Str
 	method := sm[pos+1:]
 	srv, ok := s.m[service]
 	if !ok {
+		if unknownDesc := s.opts.unknownStreamDesc; unknownDesc != nil {
+			s.processStreamingRPC(t, stream, nil, unknownDesc, trInfo)
+			return
+		}
 		if trInfo != nil {
 			trInfo.tr.LazyLog(&fmtStringer{"Unknown service %v", []interface{}{service}}, true)
 			trInfo.tr.SetError()
 		}
-		if err := t.WriteStatus(stream, codes.Unimplemented, fmt.Sprintf("unknown service %v", service)); err != nil {
+		errDesc := fmt.Sprintf("unknown service %v", service)
+		if err := t.WriteStatus(stream, status.New(codes.Unimplemented, errDesc)); err != nil {
 			if trInfo != nil {
 				trInfo.tr.LazyLog(&fmtStringer{"%v", []interface{}{err}}, true)
 				trInfo.tr.SetError()
@@ -804,7 +963,12 @@ func (s *Server) handleStream(t transport.ServerTransport, stream *transport.Str
 		trInfo.tr.LazyLog(&fmtStringer{"Unknown method %v", []interface{}{method}}, true)
 		trInfo.tr.SetError()
 	}
-	if err := t.WriteStatus(stream, codes.Unimplemented, fmt.Sprintf("unknown method %v", method)); err != nil {
+	if unknownDesc := s.opts.unknownStreamDesc; unknownDesc != nil {
+		s.processStreamingRPC(t, stream, nil, unknownDesc, trInfo)
+		return
+	}
+	errDesc := fmt.Sprintf("unknown method %v", method)
+	if err := t.WriteStatus(stream, status.New(codes.Unimplemented, errDesc)); err != nil {
 		if trInfo != nil {
 			trInfo.tr.LazyLog(&fmtStringer{"%v", []interface{}{err}}, true)
 			trInfo.tr.SetError()

vendor/google.golang.org/grpc/stats/handlers.go

@@ -0,0 +1,76 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+package stats
+
+import (
+	"net"
+
+	"golang.org/x/net/context"
+)
+
+// ConnTagInfo defines the relevant information needed by connection context tagger.
+type ConnTagInfo struct {
+	// RemoteAddr is the remote address of the corresponding connection.
+	RemoteAddr net.Addr
+	// LocalAddr is the local address of the corresponding connection.
+	LocalAddr net.Addr
+	// TODO add QOS related fields.
+}
+
+// RPCTagInfo defines the relevant information needed by RPC context tagger.
+type RPCTagInfo struct {
+	// FullMethodName is the RPC method in the format of /package.service/method.
+	FullMethodName string
+}
+
+// Handler defines the interface for the related stats handling (e.g., RPCs, connections).
+type Handler interface {
+	// TagRPC can attach some information to the given context.
+	// The returned context is used in the rest lifetime of the RPC.
+	TagRPC(context.Context, *RPCTagInfo) context.Context
+	// HandleRPC processes the RPC stats.
+	HandleRPC(context.Context, RPCStats)
+
+	// TagConn can attach some information to the given context.
+	// The returned context will be used for stats handling.
+	// For conn stats handling, the context used in HandleConn for this
+	// connection will be derived from the context returned.
+	// For RPC stats handling,
+	//  - On server side, the context used in HandleRPC for all RPCs on this
+	// connection will be derived from the context returned.
+	//  - On client side, the context is not derived from the context returned.
+	TagConn(context.Context, *ConnTagInfo) context.Context
+	// HandleConn processes the Conn stats.
+	HandleConn(context.Context, ConnStats)
+}

vendor/google.golang.org/grpc/stats/stats.go

@@ -0,0 +1,223 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+// Package stats is for collecting and reporting various network and RPC stats.
+// This package is for monitoring purpose only. All fields are read-only.
+// All APIs are experimental.
+package stats // import "google.golang.org/grpc/stats"
+
+import (
+	"net"
+	"time"
+)
+
+// RPCStats contains stats information about RPCs.
+type RPCStats interface {
+	isRPCStats()
+	// IsClient returns true if this RPCStats is from client side.
+	IsClient() bool
+}
+
+// Begin contains stats when an RPC begins.
+// FailFast are only valid if Client is true.
+type Begin struct {
+	// Client is true if this Begin is from client side.
+	Client bool
+	// BeginTime is the time when the RPC begins.
+	BeginTime time.Time
+	// FailFast indicates if this RPC is failfast.
+	FailFast bool
+}
+
+// IsClient indicates if this is from client side.
+func (s *Begin) IsClient() bool { return s.Client }
+
+func (s *Begin) isRPCStats() {}
+
+// InPayload contains the information for an incoming payload.
+type InPayload struct {
+	// Client is true if this InPayload is from client side.
+	Client bool
+	// Payload is the payload with original type.
+	Payload interface{}
+	// Data is the serialized message payload.
+	Data []byte
+	// Length is the length of uncompressed data.
+	Length int
+	// WireLength is the length of data on wire (compressed, signed, encrypted).
+	WireLength int
+	// RecvTime is the time when the payload is received.
+	RecvTime time.Time
+}
+
+// IsClient indicates if this is from client side.
+func (s *InPayload) IsClient() bool { return s.Client }
+
+func (s *InPayload) isRPCStats() {}
+
+// InHeader contains stats when a header is received.
+// FullMethod, addresses and Compression are only valid if Client is false.
+type InHeader struct {
+	// Client is true if this InHeader is from client side.
+	Client bool
+	// WireLength is the wire length of header.
+	WireLength int
+
+	// FullMethod is the full RPC method string, i.e., /package.service/method.
+	FullMethod string
+	// RemoteAddr is the remote address of the corresponding connection.
+	RemoteAddr net.Addr
+	// LocalAddr is the local address of the corresponding connection.
+	LocalAddr net.Addr
+	// Compression is the compression algorithm used for the RPC.
+	Compression string
+}
+
+// IsClient indicates if this is from client side.
+func (s *InHeader) IsClient() bool { return s.Client }
+
+func (s *InHeader) isRPCStats() {}
+
+// InTrailer contains stats when a trailer is received.
+type InTrailer struct {
+	// Client is true if this InTrailer is from client side.
+	Client bool
+	// WireLength is the wire length of trailer.
+	WireLength int
+}
+
+// IsClient indicates if this is from client side.
+func (s *InTrailer) IsClient() bool { return s.Client }
+
+func (s *InTrailer) isRPCStats() {}
+
+// OutPayload contains the information for an outgoing payload.
+type OutPayload struct {
+	// Client is true if this OutPayload is from client side.
+	Client bool
+	// Payload is the payload with original type.
+	Payload interface{}
+	// Data is the serialized message payload.
+	Data []byte
+	// Length is the length of uncompressed data.
+	Length int
+	// WireLength is the length of data on wire (compressed, signed, encrypted).
+	WireLength int
+	// SentTime is the time when the payload is sent.
+	SentTime time.Time
+}
+
+// IsClient indicates if this is from client side.
+func (s *OutPayload) IsClient() bool { return s.Client }
+
+func (s *OutPayload) isRPCStats() {}
+
+// OutHeader contains stats when a header is sent.
+// FullMethod, addresses and Compression are only valid if Client is true.
+type OutHeader struct {
+	// Client is true if this OutHeader is from client side.
+	Client bool
+	// WireLength is the wire length of header.
+	WireLength int
+
+	// FullMethod is the full RPC method string, i.e., /package.service/method.
+	FullMethod string
+	// RemoteAddr is the remote address of the corresponding connection.
+	RemoteAddr net.Addr
+	// LocalAddr is the local address of the corresponding connection.
+	LocalAddr net.Addr
+	// Compression is the compression algorithm used for the RPC.
+	Compression string
+}
+
+// IsClient indicates if this is from client side.
+func (s *OutHeader) IsClient() bool { return s.Client }
+
+func (s *OutHeader) isRPCStats() {}
+
+// OutTrailer contains stats when a trailer is sent.
+type OutTrailer struct {
+	// Client is true if this OutTrailer is from client side.
+	Client bool
+	// WireLength is the wire length of trailer.
+	WireLength int
+}
+
+// IsClient indicates if this is from client side.
+func (s *OutTrailer) IsClient() bool { return s.Client }
+
+func (s *OutTrailer) isRPCStats() {}
+
+// End contains stats when an RPC ends.
+type End struct {
+	// Client is true if this End is from client side.
+	Client bool
+	// EndTime is the time when the RPC ends.
+	EndTime time.Time
+	// Error is the error just happened.  It implements status.Status if non-nil.
+	Error error
+}
+
+// IsClient indicates if this is from client side.
+func (s *End) IsClient() bool { return s.Client }
+
+func (s *End) isRPCStats() {}
+
+// ConnStats contains stats information about connections.
+type ConnStats interface {
+	isConnStats()
+	// IsClient returns true if this ConnStats is from client side.
+	IsClient() bool
+}
+
+// ConnBegin contains the stats of a connection when it is established.
+type ConnBegin struct {
+	// Client is true if this ConnBegin is from client side.
+	Client bool
+}
+
+// IsClient indicates if this is from client side.
+func (s *ConnBegin) IsClient() bool { return s.Client }
+
+func (s *ConnBegin) isConnStats() {}
+
+// ConnEnd contains the stats of a connection when it ends.
+type ConnEnd struct {
+	// Client is true if this ConnEnd is from client side.
+	Client bool
+}
+
+// IsClient indicates if this is from client side.
+func (s *ConnEnd) IsClient() bool { return s.Client }
+
+func (s *ConnEnd) isConnStats() {}

vendor/google.golang.org/grpc/status/status.go

@@ -0,0 +1,145 @@
+/*
+ *
+ * Copyright 2017, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+// Package status implements errors returned by gRPC.  These errors are
+// serialized and transmitted on the wire between server and client, and allow
+// for additional data to be transmitted via the Details field in the status
+// proto.  gRPC service handlers should return an error created by this
+// package, and gRPC clients should expect a corresponding error to be
+// returned from the RPC call.
+//
+// This package upholds the invariants that a non-nil error may not
+// contain an OK code, and an OK code must result in a nil error.
+package status
+
+import (
+	"fmt"
+
+	"github.com/golang/protobuf/proto"
+	spb "google.golang.org/genproto/googleapis/rpc/status"
+	"google.golang.org/grpc/codes"
+)
+
+// statusError is an alias of a status proto.  It implements error and Status,
+// and a nil statusError should never be returned by this package.
+type statusError spb.Status
+
+func (se *statusError) Error() string {
+	p := (*spb.Status)(se)
+	return fmt.Sprintf("rpc error: code = %s desc = %s", codes.Code(p.GetCode()), p.GetMessage())
+}
+
+func (se *statusError) status() *Status {
+	return &Status{s: (*spb.Status)(se)}
+}
+
+// Status represents an RPC status code, message, and details.  It is immutable
+// and should be created with New, Newf, or FromProto.
+type Status struct {
+	s *spb.Status
+}
+
+// Code returns the status code contained in s.
+func (s *Status) Code() codes.Code {
+	if s == nil || s.s == nil {
+		return codes.OK
+	}
+	return codes.Code(s.s.Code)
+}
+
+// Message returns the message contained in s.
+func (s *Status) Message() string {
+	if s == nil || s.s == nil {
+		return ""
+	}
+	return s.s.Message
+}
+
+// Proto returns s's status as an spb.Status proto message.
+func (s *Status) Proto() *spb.Status {
+	if s == nil {
+		return nil
+	}
+	return proto.Clone(s.s).(*spb.Status)
+}
+
+// Err returns an immutable error representing s; returns nil if s.Code() is
+// OK.
+func (s *Status) Err() error {
+	if s.Code() == codes.OK {
+		return nil
+	}
+	return (*statusError)(s.s)
+}
+
+// New returns a Status representing c and msg.
+func New(c codes.Code, msg string) *Status {
+	return &Status{s: &spb.Status{Code: int32(c), Message: msg}}
+}
+
+// Newf returns New(c, fmt.Sprintf(format, a...)).
+func Newf(c codes.Code, format string, a ...interface{}) *Status {
+	return New(c, fmt.Sprintf(format, a...))
+}
+
+// Error returns an error representing c and msg.  If c is OK, returns nil.
+func Error(c codes.Code, msg string) error {
+	return New(c, msg).Err()
+}
+
+// Errorf returns Error(c, fmt.Sprintf(format, a...)).
+func Errorf(c codes.Code, format string, a ...interface{}) error {
+	return Error(c, fmt.Sprintf(format, a...))
+}
+
+// ErrorProto returns an error representing s.  If s.Code is OK, returns nil.
+func ErrorProto(s *spb.Status) error {
+	return FromProto(s).Err()
+}
+
+// FromProto returns a Status representing s.
+func FromProto(s *spb.Status) *Status {
+	return &Status{s: proto.Clone(s).(*spb.Status)}
+}
+
+// FromError returns a Status representing err if it was produced from this
+// package, otherwise it returns nil, false.
+func FromError(err error) (s *Status, ok bool) {
+	if err == nil {
+		return &Status{s: &spb.Status{Code: int32(codes.OK)}}, true
+	}
+	if s, ok := err.(*statusError); ok {
+		return s.status(), true
+	}
+	return nil, false
+}

vendor/google.golang.org/grpc/stream.go

@@ -37,7 +37,6 @@ import (
 	"bytes"
 	"errors"
 	"io"
-	"math"
 	"sync"
 	"time"
 
@@ -45,6 +44,8 @@ import (
 	"golang.org/x/net/trace"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
 	"google.golang.org/grpc/transport"
 )
 
@@ -97,7 +98,7 @@ type ClientStream interface {
 
 // NewClientStream creates a new Stream for the client side. This is called
 // by generated code.
-func NewClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, method string, opts ...CallOption) (ClientStream, error) {
+func NewClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, method string, opts ...CallOption) (_ ClientStream, err error) {
 	if cc.dopts.streamInt != nil {
 		return cc.dopts.streamInt(ctx, desc, cc, method, newClientStream, opts...)
 	}
@@ -109,8 +110,15 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 		t      transport.ClientTransport
 		s      *transport.Stream
 		put    func()
+		cancel context.CancelFunc
 	)
 	c := defaultCallInfo
+	if mc, ok := cc.getMethodConfig(method); ok {
+		c.failFast = !mc.WaitForReady
+		if mc.Timeout > 0 {
+			ctx, cancel = context.WithTimeout(ctx, mc.Timeout)
+		}
+	}
 	for _, o := range opts {
 		if err := o.before(&c); err != nil {
 			return nil, toRPCErr(err)
@@ -143,6 +151,27 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 			}
 		}()
 	}
+	ctx = newContextWithRPCInfo(ctx)
+	sh := cc.dopts.copts.StatsHandler
+	if sh != nil {
+		ctx = sh.TagRPC(ctx, &stats.RPCTagInfo{FullMethodName: method})
+		begin := &stats.Begin{
+			Client:    true,
+			BeginTime: time.Now(),
+			FailFast:  c.failFast,
+		}
+		sh.HandleRPC(ctx, begin)
+	}
+	defer func() {
+		if err != nil && sh != nil {
+			// Only handle end stats if err != nil.
+			end := &stats.End{
+				Client: true,
+				Error:  err,
+			}
+			sh.HandleRPC(ctx, end)
+		}
+	}()
 	gopts := BalancerGetOptions{
 		BlockingWait: !c.failFast,
 	}
@@ -150,7 +179,7 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 		t, put, err = cc.getTransport(ctx, gopts)
 		if err != nil {
 			// TODO(zhaoq): Probably revisit the error handling.
-			if _, ok := err.(*rpcError); ok {
+			if _, ok := status.FromError(err); ok {
 				return nil, err
 			}
 			if err == errConnClosing || err == errConnUnavailable {
@@ -165,14 +194,17 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 
 		s, err = t.NewStream(ctx, callHdr)
 		if err != nil {
+			if _, ok := err.(transport.ConnectionError); ok && put != nil {
+				// If error is connection error, transport was sending data on wire,
+				// and we are not sure if anything has been sent on wire.
+				// If error is not connection error, we are sure nothing has been sent.
+				updateRPCInfoInContext(ctx, rpcInfo{bytesSent: true, bytesReceived: false})
+			}
 			if put != nil {
 				put()
 				put = nil
 			}
-			if _, ok := err.(transport.ConnectionError); ok || err == transport.ErrStreamDrain {
+			if _, ok := err.(transport.ConnectionError); (ok || err == transport.ErrStreamDrain) && !c.failFast {
-				if c.failFast {
-					return nil, toRPCErr(err)
-				}
 				continue
 			}
 			return nil, toRPCErr(err)
@@ -186,6 +218,8 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 		codec:      cc.dopts.codec,
 		cp:         cc.dopts.cp,
 		dc:         cc.dopts.dc,
+		maxMsgSize: cc.dopts.maxMsgSize,
+		cancel:     cancel,
 
 		put: put,
 		t:   t,
@@ -194,6 +228,9 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 
 		tracing: EnableTracing,
 		trInfo:  trInfo,
+
+		statsCtx:     ctx,
+		statsHandler: cc.dopts.copts.StatsHandler,
 	}
 	if cc.dopts.cp != nil {
 		cs.cbuf = new(bytes.Buffer)
@@ -204,14 +241,13 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 		select {
 		case <-t.Error():
 			// Incur transport error, simply exit.
+		case <-cc.ctx.Done():
+			cs.finish(ErrClientConnClosing)
+			cs.closeTransportStream(ErrClientConnClosing)
 		case <-s.Done():
 			// TODO: The trace of the RPC is terminated here when there is no pending
 			// I/O, which is probably not the optimal solution.
-			if s.StatusCode() == codes.OK {
+			cs.finish(s.Status().Err())
-				cs.finish(nil)
-			} else {
-				cs.finish(Errorf(s.StatusCode(), "%s", s.StatusDesc()))
-			}
 			cs.closeTransportStream(nil)
 		case <-s.GoAway():
 			cs.finish(errConnDrain)
@@ -237,15 +273,24 @@ type clientStream struct {
 	cp         Compressor
 	cbuf       *bytes.Buffer
 	dc         Decompressor
+	maxMsgSize int
+	cancel     context.CancelFunc
 
 	tracing bool // set to EnableTracing when the clientStream is created.
 
 	mu       sync.Mutex
 	put      func()
 	closed   bool
+	finished bool
 	// trInfo.tr is set when the clientStream is created (if EnableTracing is true),
 	// and is set to nil when the clientStream's finish method is called.
 	trInfo traceInfo
+
+	// statsCtx keeps the user context for stats handling.
+	// All stats collection should use the statsCtx (instead of the stream context)
+	// so that all the generated stats for a particular RPC can be associated in the processing phase.
+	statsCtx     context.Context
+	statsHandler stats.Handler
 }
 
 func (cs *clientStream) Context() context.Context {
@@ -274,6 +319,8 @@ func (cs *clientStream) SendMsg(m interface{}) (err error) {
 		}
 		cs.mu.Unlock()
 	}
+	// TODO Investigate how to signal the stats handling party.
+	// generate error stats if err != nil && err != io.EOF?
 	defer func() {
 		if err != nil {
 			cs.finish(err)
@@ -296,7 +343,13 @@ func (cs *clientStream) SendMsg(m interface{}) (err error) {
 		}
 		err = toRPCErr(err)
 	}()
-	out, err := encode(cs.codec, m, cs.cp, cs.cbuf)
+	var outPayload *stats.OutPayload
+	if cs.statsHandler != nil {
+		outPayload = &stats.OutPayload{
+			Client: true,
+		}
+	}
+	out, err := encode(cs.codec, m, cs.cp, cs.cbuf, outPayload)
 	defer func() {
 		if cs.cbuf != nil {
 			cs.cbuf.Reset()
@@ -305,11 +358,22 @@ func (cs *clientStream) SendMsg(m interface{}) (err error) {
 	if err != nil {
 		return Errorf(codes.Internal, "grpc: %v", err)
 	}
-	return cs.t.Write(cs.s, out, &transport.Options{Last: false})
+	err = cs.t.Write(cs.s, out, &transport.Options{Last: false})
+	if err == nil && outPayload != nil {
+		outPayload.SentTime = time.Now()
+		cs.statsHandler.HandleRPC(cs.statsCtx, outPayload)
+	}
+	return err
 }
 
 func (cs *clientStream) RecvMsg(m interface{}) (err error) {
-	err = recv(cs.p, cs.codec, cs.s, cs.dc, m, math.MaxInt32)
+	var inPayload *stats.InPayload
+	if cs.statsHandler != nil {
+		inPayload = &stats.InPayload{
+			Client: true,
+		}
+	}
+	err = recv(cs.p, cs.codec, cs.s, cs.dc, m, cs.maxMsgSize, inPayload)
 	defer func() {
 		// err != nil indicates the termination of the stream.
 		if err != nil {
@@ -324,34 +388,38 @@ func (cs *clientStream) RecvMsg(m interface{}) (err error) {
 			}
 			cs.mu.Unlock()
 		}
+		if inPayload != nil {
+			cs.statsHandler.HandleRPC(cs.statsCtx, inPayload)
+		}
 		if !cs.desc.ClientStreams || cs.desc.ServerStreams {
 			return
 		}
 		// Special handling for client streaming rpc.
-		err = recv(cs.p, cs.codec, cs.s, cs.dc, m, math.MaxInt32)
+		// This recv expects EOF or errors, so we don't collect inPayload.
+		err = recv(cs.p, cs.codec, cs.s, cs.dc, m, cs.maxMsgSize, nil)
 		cs.closeTransportStream(err)
 		if err == nil {
 			return toRPCErr(errors.New("grpc: client streaming protocol violation: get <nil>, want <EOF>"))
 		}
 		if err == io.EOF {
-			if cs.s.StatusCode() == codes.OK {
+			if se := cs.s.Status().Err(); se != nil {
+				return se
+			}
 			cs.finish(err)
 			return nil
 		}
-			return Errorf(cs.s.StatusCode(), "%s", cs.s.StatusDesc())
-		}
 		return toRPCErr(err)
 	}
 	if _, ok := err.(transport.ConnectionError); !ok {
 		cs.closeTransportStream(err)
 	}
 	if err == io.EOF {
-		if cs.s.StatusCode() == codes.OK {
+		if statusErr := cs.s.Status().Err(); statusErr != nil {
+			return statusErr
+		}
 		// Returns io.EOF to indicate the end of the stream.
 		return
 	}
-		return Errorf(cs.s.StatusCode(), "%s", cs.s.StatusDesc())
-	}
 	return toRPCErr(err)
 }
 
@@ -386,13 +454,37 @@ func (cs *clientStream) closeTransportStream(err error) {
 func (cs *clientStream) finish(err error) {
 	cs.mu.Lock()
 	defer cs.mu.Unlock()
+	if cs.finished {
+		return
+	}
+	cs.finished = true
+	defer func() {
+		if cs.cancel != nil {
+			cs.cancel()
+		}
+	}()
 	for _, o := range cs.opts {
 		o.after(&cs.c)
 	}
 	if cs.put != nil {
+		updateRPCInfoInContext(cs.s.Context(), rpcInfo{
+			bytesSent:     cs.s.BytesSent(),
+			bytesReceived: cs.s.BytesReceived(),
+		})
 		cs.put()
 		cs.put = nil
 	}
+	if cs.statsHandler != nil {
+		end := &stats.End{
+			Client:  true,
+			EndTime: time.Now(),
+		}
+		if err != io.EOF {
+			// end.Error is nil if the RPC finished successfully.
+			end.Error = toRPCErr(err)
+		}
+		cs.statsHandler.HandleRPC(cs.statsCtx, end)
+	}
 	if !cs.tracing {
 		return
 	}
@@ -437,10 +529,10 @@ type serverStream struct {
 	dc         Decompressor
 	cbuf       *bytes.Buffer
 	maxMsgSize int
-	statusCode codes.Code
-	statusDesc string
 	trInfo     *traceInfo
 
+	statsHandler stats.Handler
+
 	mu sync.Mutex // protects trInfo.tr after the service handler runs.
 }
 
@@ -482,7 +574,11 @@ func (ss *serverStream) SendMsg(m interface{}) (err error) {
 			ss.mu.Unlock()
 		}
 	}()
-	out, err := encode(ss.codec, m, ss.cp, ss.cbuf)
+	var outPayload *stats.OutPayload
+	if ss.statsHandler != nil {
+		outPayload = &stats.OutPayload{}
+	}
+	out, err := encode(ss.codec, m, ss.cp, ss.cbuf, outPayload)
 	defer func() {
 		if ss.cbuf != nil {
 			ss.cbuf.Reset()
@@ -495,6 +591,10 @@ func (ss *serverStream) SendMsg(m interface{}) (err error) {
 	if err := ss.t.Write(ss.s, out, &transport.Options{Last: false}); err != nil {
 		return toRPCErr(err)
 	}
+	if outPayload != nil {
+		outPayload.SentTime = time.Now()
+		ss.statsHandler.HandleRPC(ss.s.Context(), outPayload)
+	}
 	return nil
 }
 
@@ -513,7 +613,11 @@ func (ss *serverStream) RecvMsg(m interface{}) (err error) {
 			ss.mu.Unlock()
 		}
 	}()
-	if err := recv(ss.p, ss.codec, ss.s, ss.dc, m, ss.maxMsgSize); err != nil {
+	var inPayload *stats.InPayload
+	if ss.statsHandler != nil {
+		inPayload = &stats.InPayload{}
+	}
+	if err := recv(ss.p, ss.codec, ss.s, ss.dc, m, ss.maxMsgSize, inPayload); err != nil {
 		if err == io.EOF {
 			return err
 		}
@@ -522,5 +626,8 @@ func (ss *serverStream) RecvMsg(m interface{}) (err error) {
 		}
 		return toRPCErr(err)
 	}
+	if inPayload != nil {
+		ss.statsHandler.HandleRPC(ss.s.Context(), inPayload)
+	}
 	return nil
 }

vendor/google.golang.org/grpc/tap/tap.go

@@ -0,0 +1,54 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+// Package tap defines the function handles which are executed on the transport
+// layer of gRPC-Go and related information. Everything here is EXPERIMENTAL.
+package tap
+
+import (
+	"golang.org/x/net/context"
+)
+
+// Info defines the relevant information needed by the handles.
+type Info struct {
+	// FullMethodName is the string of grpc method (in the format of
+	// /package.service/method).
+	FullMethodName string
+	// TODO: More to be added.
+}
+
+// ServerInHandle defines the function which runs when a new stream is created
+// on the server side. Note that it is executed in the per-connection I/O goroutine(s) instead
+// of per-RPC goroutine. Therefore, users should NOT have any blocking/time-consuming
+// work in this handle. Otherwise all the RPCs would slow down.
+type ServerInHandle func(ctx context.Context, info *Info) (context.Context, error)

vendor/google.golang.org/grpc/transport/control.go

@@ -35,7 +35,9 @@ package transport
 
 import (
 	"fmt"
+	"math"
 	"sync"
+	"time"
 
 	"golang.org/x/net/http2"
 )
@@ -46,6 +48,16 @@ const (
 	// The initial window size for flow control.
 	initialWindowSize             = defaultWindowSize      // for an RPC
 	initialConnWindowSize         = defaultWindowSize * 16 // for a connection
+	infinity                      = time.Duration(math.MaxInt64)
+	defaultClientKeepaliveTime    = infinity
+	defaultClientKeepaliveTimeout = time.Duration(20 * time.Second)
+	defaultMaxStreamsClient       = 100
+	defaultMaxConnectionIdle      = infinity
+	defaultMaxConnectionAge       = infinity
+	defaultMaxConnectionAgeGrace  = infinity
+	defaultServerKeepaliveTime    = time.Duration(2 * time.Hour)
+	defaultServerKeepaliveTimeout = time.Duration(20 * time.Second)
+	defaultKeepalivePolicyMinTime = time.Duration(5 * time.Minute)
 )
 
 // The following defines various control items which could flow through
@@ -73,6 +85,8 @@ type resetStream struct {
 func (*resetStream) item() {}
 
 type goAway struct {
+	code      http2.ErrCode
+	debugData []byte
 }
 
 func (*goAway) item() {}
@@ -111,35 +125,9 @@ func newQuotaPool(q int) *quotaPool {
 	return qb
 }
 
-// add adds n to the available quota and tries to send it on acquire.
+// add cancels the pending quota sent on acquired, incremented by v and sends
-func (qb *quotaPool) add(n int) {
-	qb.mu.Lock()
-	defer qb.mu.Unlock()
-	qb.quota += n
-	if qb.quota <= 0 {
-		return
-	}
-	select {
-	case qb.c <- qb.quota:
-		qb.quota = 0
-	default:
-	}
-}
-
-// cancel cancels the pending quota sent on acquire, if any.
-func (qb *quotaPool) cancel() {
-	qb.mu.Lock()
-	defer qb.mu.Unlock()
-	select {
-	case n := <-qb.c:
-		qb.quota += n
-	default:
-	}
-}
-
-// reset cancels the pending quota sent on acquired, incremented by v and sends
 // it back on acquire.
-func (qb *quotaPool) reset(v int) {
+func (qb *quotaPool) add(v int) {
 	qb.mu.Lock()
 	defer qb.mu.Unlock()
 	select {
@@ -151,6 +139,10 @@ func (qb *quotaPool) reset(v int) {
 	if qb.quota <= 0 {
 		return
 	}
+	// After the pool has been created, this is the only place that sends on
+	// the channel. Since mu is held at this point and any quota that was sent
+	// on the channel has been retrieved, we know that this code will always
+	// place any positive quota value on the channel.
 	select {
 	case qb.c <- qb.quota:
 		qb.quota = 0

vendor/google.golang.org/grpc/transport/handler_server.go

@@ -53,6 +53,7 @@ import (
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/peer"
+	"google.golang.org/grpc/status"
 )
 
 // NewServerHandlerTransport returns a ServerTransport handling gRPC
@@ -110,6 +111,10 @@ func NewServerHandlerTransport(w http.ResponseWriter, r *http.Request) (ServerTr
 					v = v[:i]
 				}
 			}
+			v, err := decodeMetadataHeader(k, v)
+			if err != nil {
+				return nil, streamErrorf(codes.InvalidArgument, "malformed binary metadata: %v", err)
+			}
 			metakv = append(metakv, k, v)
 		}
 	}
@@ -182,7 +187,7 @@ func (ht *serverHandlerTransport) do(fn func()) error {
 	}
 }
 
-func (ht *serverHandlerTransport) WriteStatus(s *Stream, statusCode codes.Code, statusDesc string) error {
+func (ht *serverHandlerTransport) WriteStatus(s *Stream, st *status.Status) error {
 	err := ht.do(func() {
 		ht.writeCommonHeaders(s)
 
@@ -192,10 +197,13 @@ func (ht *serverHandlerTransport) WriteStatus(s *Stream, statusCode codes.Code,
 		ht.rw.(http.Flusher).Flush()
 
 		h := ht.rw.Header()
-		h.Set("Grpc-Status", fmt.Sprintf("%d", statusCode))
+		h.Set("Grpc-Status", fmt.Sprintf("%d", st.Code()))
-		if statusDesc != "" {
+		if m := st.Message(); m != "" {
-			h.Set("Grpc-Message", encodeGrpcMessage(statusDesc))
+			h.Set("Grpc-Message", encodeGrpcMessage(m))
 		}
+
+		// TODO: Support Grpc-Status-Details-Bin
+
 		if md := s.Trailer(); len(md) > 0 {
 			for k, vv := range md {
 				// Clients don't tolerate reading restricted headers after some non restricted ones were sent.
@@ -203,10 +211,9 @@ func (ht *serverHandlerTransport) WriteStatus(s *Stream, statusCode codes.Code,
 					continue
 				}
 				for _, v := range vv {
-					// http2 ResponseWriter mechanism to
+					// http2 ResponseWriter mechanism to send undeclared Trailers after
-					// send undeclared Trailers after the
+					// the headers have possibly been written.
-					// headers have possibly been written.
+					h.Add(http2.TrailerPrefix+k, encodeMetadataHeader(k, v))
-					h.Add(http2.TrailerPrefix+k, v)
 				}
 			}
 		}
@@ -234,6 +241,7 @@ func (ht *serverHandlerTransport) writeCommonHeaders(s *Stream) {
 	// and https://golang.org/pkg/net/http/#example_ResponseWriter_trailers
 	h.Add("Trailer", "Grpc-Status")
 	h.Add("Trailer", "Grpc-Message")
+	// TODO: Support Grpc-Status-Details-Bin
 
 	if s.sendCompress != "" {
 		h.Set("Grpc-Encoding", s.sendCompress)
@@ -260,6 +268,7 @@ func (ht *serverHandlerTransport) WriteHeader(s *Stream, md metadata.MD) error {
 				continue
 			}
 			for _, v := range vv {
+				v = encodeMetadataHeader(k, v)
 				h.Add(k, v)
 			}
 		}
@@ -268,7 +277,7 @@ func (ht *serverHandlerTransport) WriteHeader(s *Stream, md metadata.MD) error {
 	})
 }
 
-func (ht *serverHandlerTransport) HandleStreams(startStream func(*Stream)) {
+func (ht *serverHandlerTransport) HandleStreams(startStream func(*Stream), traceCtx func(context.Context, string) context.Context) {
 	// With this transport type there will be exactly 1 stream: this HTTP request.
 
 	var ctx context.Context
@@ -314,7 +323,7 @@ func (ht *serverHandlerTransport) HandleStreams(startStream func(*Stream)) {
 	if req.TLS != nil {
 		pr.AuthInfo = credentials.TLSInfo{State: *req.TLS}
 	}
-	ctx = metadata.NewContext(ctx, ht.headerMD)
+	ctx = metadata.NewIncomingContext(ctx, ht.headerMD)
 	ctx = peer.NewContext(ctx, pr)
 	s.ctx = newContextWithStream(ctx, s)
 	s.dec = &recvBufferReader{ctx: s.ctx, recv: s.buf}

vendor/google.golang.org/grpc/transport/http2_client.go

@@ -35,12 +35,12 @@ package transport
 
 import (
 	"bytes"
-	"fmt"
 	"io"
 	"math"
 	"net"
 	"strings"
 	"sync"
+	"sync/atomic"
 	"time"
 
 	"golang.org/x/net/context"
@@ -49,16 +49,22 @@ import (
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/keepalive"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/peer"
+	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
 )
 
 // http2Client implements the ClientTransport interface with HTTP2.
 type http2Client struct {
+	ctx        context.Context
 	target     string // server name/addr
 	userAgent  string
 	md         interface{}
 	conn       net.Conn // underlying communication channel
+	remoteAddr net.Addr
+	localAddr  net.Addr
 	authInfo   credentials.AuthInfo // auth info about the connection
 	nextID     uint32               // the next stream ID to be used
 
@@ -76,6 +82,8 @@ type http2Client struct {
 	// goAway is closed to notify the upper layer (i.e., addrConn.transportMonitor)
 	// that the server sent GoAway on this transport.
 	goAway chan struct{}
+	// awakenKeepalive is used to wake up keepalive when after it has gone dormant.
+	awakenKeepalive chan struct{}
 
 	framer *framer
 	hBuf   *bytes.Buffer  // the buffer for HPACK encoding
@@ -95,6 +103,13 @@ type http2Client struct {
 
 	creds []credentials.PerRPCCredentials
 
+	// Boolean to keep track of reading activity on transport.
+	// 1 is true and 0 is false.
+	activity uint32 // Accessed atomically.
+	kp       keepalive.ClientParameters
+
+	statsHandler stats.Handler
+
 	mu            sync.Mutex     // guard the following variables
 	state         transportState // the state of underlying connection
 	activeStreams map[uint32]*Stream
@@ -106,6 +121,9 @@ type http2Client struct {
 	goAwayID uint32
 	// prevGoAway ID records the Last-Stream-ID in the previous GOAway frame.
 	prevGoAwayID uint32
+	// goAwayReason records the http2.ErrCode and debug data received with the
+	// GoAway frame.
+	goAwayReason GoAwayReason
 }
 
 func dial(ctx context.Context, fn func(context.Context, string) (net.Conn, error), addr string) (net.Conn, error) {
@@ -150,6 +168,9 @@ func newHTTP2Client(ctx context.Context, addr TargetInfo, opts ConnectOptions) (
 	scheme := "http"
 	conn, err := dial(ctx, opts.Dialer, addr.Addr)
 	if err != nil {
+		if opts.FailOnNonTempDialError {
+			return nil, connectionErrorf(isTemporary(err), err, "transport: %v", err)
+		}
 		return nil, connectionErrorf(true, err, "transport: %v", err)
 	}
 	// Any further errors will close the underlying connection
@@ -169,16 +190,23 @@ func newHTTP2Client(ctx context.Context, addr TargetInfo, opts ConnectOptions) (
 			return nil, connectionErrorf(temp, err, "transport: %v", err)
 		}
 	}
-	ua := primaryUA
+	kp := opts.KeepaliveParams
-	if opts.UserAgent != "" {
+	// Validate keepalive parameters.
-		ua = opts.UserAgent + " " + ua
+	if kp.Time == 0 {
+		kp.Time = defaultClientKeepaliveTime
+	}
+	if kp.Timeout == 0 {
+		kp.Timeout = defaultClientKeepaliveTimeout
 	}
 	var buf bytes.Buffer
 	t := &http2Client{
+		ctx:        ctx,
 		target:     addr.Addr,
-		userAgent: ua,
+		userAgent:  opts.UserAgent,
 		md:         addr.Metadata,
 		conn:       conn,
+		remoteAddr: conn.RemoteAddr(),
+		localAddr:  conn.LocalAddr(),
 		authInfo:   authInfo,
 		// The client initiated stream id is odd starting from 1.
 		nextID:          1,
@@ -186,6 +214,7 @@ func newHTTP2Client(ctx context.Context, addr TargetInfo, opts ConnectOptions) (
 		shutdownChan:    make(chan struct{}),
 		errorChan:       make(chan struct{}),
 		goAway:          make(chan struct{}),
+		awakenKeepalive: make(chan struct{}, 1),
 		framer:          newFramer(conn),
 		hBuf:            &buf,
 		hEnc:            hpack.NewEncoder(&buf),
@@ -196,8 +225,24 @@ func newHTTP2Client(ctx context.Context, addr TargetInfo, opts ConnectOptions) (
 		state:           reachable,
 		activeStreams:   make(map[uint32]*Stream),
 		creds:           opts.PerRPCCredentials,
-		maxStreams:      math.MaxInt32,
+		maxStreams:      defaultMaxStreamsClient,
+		streamsQuota:    newQuotaPool(defaultMaxStreamsClient),
 		streamSendQuota: defaultWindowSize,
+		kp:              kp,
+		statsHandler:    opts.StatsHandler,
+	}
+	// Make sure awakenKeepalive can't be written upon.
+	// keepalive routine will make it writable, if need be.
+	t.awakenKeepalive <- struct{}{}
+	if t.statsHandler != nil {
+		t.ctx = t.statsHandler.TagConn(t.ctx, &stats.ConnTagInfo{
+			RemoteAddr: t.remoteAddr,
+			LocalAddr:  t.localAddr,
+		})
+		connBegin := &stats.ConnBegin{
+			Client: true,
+		}
+		t.statsHandler.HandleConn(t.ctx, connBegin)
 	}
 	// Start the reader goroutine for incoming message. Each transport has
 	// a dedicated goroutine which reads HTTP2 frame from network. Then it
@@ -233,6 +278,9 @@ func newHTTP2Client(ctx context.Context, addr TargetInfo, opts ConnectOptions) (
 		}
 	}
 	go t.controller()
+	if t.kp.Time != infinity {
+		go t.keepalive()
+	}
 	t.writableChan <- 0
 	return t, nil
 }
@@ -266,16 +314,17 @@ func (t *http2Client) newStream(ctx context.Context, callHdr *CallHdr) *Stream {
 	return s
 }
 
-// NewStream creates a stream and register it into the transport as "active"
+// NewStream creates a stream and registers it into the transport as "active"
 // streams.
 func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Stream, err error) {
 	pr := &peer.Peer{
-		Addr: t.conn.RemoteAddr(),
+		Addr: t.remoteAddr,
 	}
 	// Attach Auth info if there is any.
 	if t.authInfo != nil {
 		pr.AuthInfo = t.authInfo
 	}
+	userCtx := ctx
 	ctx = peer.NewContext(ctx, pr)
 	authData := make(map[string]string)
 	for _, c := range t.creds {
@@ -313,9 +362,7 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Strea
 		t.mu.Unlock()
 		return nil, ErrConnClosing
 	}
-	checkStreamsQuota := t.streamsQuota != nil
 	t.mu.Unlock()
-	if checkStreamsQuota {
 	sq, err := wait(ctx, nil, nil, t.shutdownChan, t.streamsQuota.acquire())
 	if err != nil {
 		return nil, err
@@ -324,10 +371,9 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Strea
 	if sq > 1 {
 		t.streamsQuota.add(sq - 1)
 	}
-	}
 	if _, err := wait(ctx, nil, nil, t.shutdownChan, t.writableChan); err != nil {
 		// Return the quota back now because there is no stream returned to the caller.
-		if _, ok := err.(StreamError); ok && checkStreamsQuota {
+		if _, ok := err.(StreamError); ok {
 			t.streamsQuota.add(1)
 		}
 		return nil, err
@@ -335,9 +381,7 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Strea
 	t.mu.Lock()
 	if t.state == draining {
 		t.mu.Unlock()
-		if checkStreamsQuota {
 		t.streamsQuota.add(1)
-		}
 		// Need to make t writable again so that the rpc in flight can still proceed.
 		t.writableChan <- 0
 		return nil, ErrStreamDrain
@@ -347,18 +391,19 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Strea
 		return nil, ErrConnClosing
 	}
 	s := t.newStream(ctx, callHdr)
+	s.clientStatsCtx = userCtx
 	t.activeStreams[s.id] = s
+	// If the number of active streams change from 0 to 1, then check if keepalive
+	// has gone dormant. If so, wake it up.
+	if len(t.activeStreams) == 1 {
+		select {
+		case t.awakenKeepalive <- struct{}{}:
+			t.framer.writePing(false, false, [8]byte{})
+		default:
+		}
+	}
 
-	// This stream is not counted when applySetings(...) initialize t.streamsQuota.
-	// Reset t.streamsQuota to the right value.
-	var reset bool
-	if !checkStreamsQuota && t.streamsQuota != nil {
-		reset = true
-	}
 	t.mu.Unlock()
-	if reset {
-		t.streamsQuota.reset(-1)
-	}
 
 	// HPACK encodes various headers. Note that once WriteField(...) is
 	// called, the corresponding headers/continuation frame has to be sent
@@ -390,29 +435,30 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Strea
 		hasMD      bool
 		endHeaders bool
 	)
-	if md, ok := metadata.FromContext(ctx); ok {
+	if md, ok := metadata.FromOutgoingContext(ctx); ok {
 		hasMD = true
-		for k, v := range md {
+		for k, vv := range md {
 			// HTTP doesn't allow you to set pseudoheaders after non pseudoheaders were set.
 			if isReservedHeader(k) {
 				continue
 			}
-			for _, entry := range v {
+			for _, v := range vv {
-				t.hEnc.WriteField(hpack.HeaderField{Name: k, Value: entry})
+				t.hEnc.WriteField(hpack.HeaderField{Name: k, Value: encodeMetadataHeader(k, v)})
 			}
 		}
 	}
 	if md, ok := t.md.(*metadata.MD); ok {
-		for k, v := range *md {
+		for k, vv := range *md {
 			if isReservedHeader(k) {
 				continue
 			}
-			for _, entry := range v {
+			for _, v := range vv {
-				t.hEnc.WriteField(hpack.HeaderField{Name: k, Value: entry})
+				t.hEnc.WriteField(hpack.HeaderField{Name: k, Value: encodeMetadataHeader(k, v)})
 			}
 		}
 	}
 	first := true
+	bufLen := t.hBuf.Len()
 	// Sends the headers in a single batch even when they span multiple frames.
 	for !endHeaders {
 		size := t.hBuf.Len()
@@ -447,6 +493,19 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Strea
 			return nil, connectionErrorf(true, err, "transport: %v", err)
 		}
 	}
+	s.bytesSent = true
+
+	if t.statsHandler != nil {
+		outHeader := &stats.OutHeader{
+			Client:      true,
+			WireLength:  bufLen,
+			FullMethod:  callHdr.Method,
+			RemoteAddr:  t.remoteAddr,
+			LocalAddr:   t.localAddr,
+			Compression: callHdr.SendCompress,
+		}
+		t.statsHandler.HandleRPC(s.clientStatsCtx, outHeader)
+	}
 	t.writableChan <- 0
 	return s, nil
 }
@@ -454,15 +513,11 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Strea
 // CloseStream clears the footprint of a stream when the stream is not needed any more.
 // This must not be executed in reader's goroutine.
 func (t *http2Client) CloseStream(s *Stream, err error) {
-	var updateStreams bool
 	t.mu.Lock()
 	if t.activeStreams == nil {
 		t.mu.Unlock()
 		return
 	}
-	if t.streamsQuota != nil {
-		updateStreams = true
-	}
 	delete(t.activeStreams, s.id)
 	if t.state == draining && len(t.activeStreams) == 0 {
 		// The transport is draining and s is the last live stream on t.
@@ -471,10 +526,27 @@ func (t *http2Client) CloseStream(s *Stream, err error) {
 		return
 	}
 	t.mu.Unlock()
-	if updateStreams {
+	// rstStream is true in case the stream is being closed at the client-side
+	// and the server needs to be intimated about it by sending a RST_STREAM
+	// frame.
+	// To make sure this frame is written to the wire before the headers of the
+	// next stream waiting for streamsQuota, we add to streamsQuota pool only
+	// after having acquired the writableChan to send RST_STREAM out (look at
+	// the controller() routine).
+	var rstStream bool
+	var rstError http2.ErrCode
+	defer func() {
+		// In case, the client doesn't have to send RST_STREAM to server
+		// we can safely add back to streamsQuota pool now.
+		if !rstStream {
 			t.streamsQuota.add(1)
+			return
 		}
+		t.controlBuf.put(&resetStream{s.id, rstError})
+	}()
 	s.mu.Lock()
+	rstStream = s.rstStream
+	rstError = s.rstError
 	if q := s.fc.resetPendingData(); q > 0 {
 		if n := t.fc.onRead(q); n > 0 {
 			t.controlBuf.put(&windowUpdate{0, n})
@@ -490,8 +562,9 @@ func (t *http2Client) CloseStream(s *Stream, err error) {
 	}
 	s.state = streamDone
 	s.mu.Unlock()
-	if se, ok := err.(StreamError); ok && se.Code != codes.DeadlineExceeded {
+	if _, ok := err.(StreamError); ok {
-		t.controlBuf.put(&resetStream{s.id, http2.ErrCodeCancel})
+		rstStream = true
+		rstError = http2.ErrCodeCancel
 	}
 }
 
@@ -525,6 +598,12 @@ func (t *http2Client) Close() (err error) {
 		s.mu.Unlock()
 		s.write(recvMsg{err: ErrConnClosing})
 	}
+	if t.statsHandler != nil {
+		connEnd := &stats.ConnEnd{
+			Client: true,
+		}
+		t.statsHandler.HandleConn(t.ctx, connEnd)
+	}
 	return
 }
 
@@ -582,19 +661,14 @@ func (t *http2Client) Write(s *Stream, data []byte, opts *Options) error {
 		var p []byte
 		if r.Len() > 0 {
 			size := http2MaxFrameLen
-			s.sendQuotaPool.add(0)
 			// Wait until the stream has some quota to send the data.
 			sq, err := wait(s.ctx, s.done, s.goAway, t.shutdownChan, s.sendQuotaPool.acquire())
 			if err != nil {
 				return err
 			}
-			t.sendQuotaPool.add(0)
 			// Wait until the transport has some quota to send the data.
 			tq, err := wait(s.ctx, s.done, s.goAway, t.shutdownChan, t.sendQuotaPool.acquire())
 			if err != nil {
-				if _, ok := err.(StreamError); ok || err == io.EOF {
-					t.sendQuotaPool.cancel()
-				}
 				return err
 			}
 			if sq < size {
@@ -704,7 +778,7 @@ func (t *http2Client) updateWindow(s *Stream, n uint32) {
 }
 
 func (t *http2Client) handleData(f *http2.DataFrame) {
-	size := len(f.Data())
+	size := f.Header().Length
 	if err := t.fc.onData(uint32(size)); err != nil {
 		t.notifyError(connectionErrorf(true, err, "%v", err))
 		return
@@ -718,6 +792,11 @@ func (t *http2Client) handleData(f *http2.DataFrame) {
 		return
 	}
 	if size > 0 {
+		if f.Header().Flags.Has(http2.FlagDataPadded) {
+			if w := t.fc.onRead(uint32(size) - uint32(len(f.Data()))); w > 0 {
+				t.controlBuf.put(&windowUpdate{0, w})
+			}
+		}
 		s.mu.Lock()
 		if s.state == streamDone {
 			s.mu.Unlock()
@@ -728,23 +807,28 @@ func (t *http2Client) handleData(f *http2.DataFrame) {
 			return
 		}
 		if err := s.fc.onData(uint32(size)); err != nil {
-			s.state = streamDone
+			s.rstStream = true
-			s.statusCode = codes.Internal
+			s.rstError = http2.ErrCodeFlowControl
-			s.statusDesc = err.Error()
+			s.finish(status.New(codes.Internal, err.Error()))
-			close(s.done)
 			s.mu.Unlock()
 			s.write(recvMsg{err: io.EOF})
-			t.controlBuf.put(&resetStream{s.id, http2.ErrCodeFlowControl})
 			return
 		}
+		if f.Header().Flags.Has(http2.FlagDataPadded) {
+			if w := s.fc.onRead(uint32(size) - uint32(len(f.Data()))); w > 0 {
+				t.controlBuf.put(&windowUpdate{s.id, w})
+			}
+		}
 		s.mu.Unlock()
 		// TODO(bradfitz, zhaoq): A copy is required here because there is no
 		// guarantee f.Data() is consumed before the arrival of next frame.
 		// Can this copy be eliminated?
-		data := make([]byte, size)
+		if len(f.Data()) > 0 {
+			data := make([]byte, len(f.Data()))
 			copy(data, f.Data())
 			s.write(recvMsg{data: data})
 		}
+	}
 	// The server has closed the stream without sending trailers.  Record that
 	// the read direction is closed, and set the status appropriately.
 	if f.FrameHeader.Flags.Has(http2.FlagDataEndStream) {
@@ -753,10 +837,7 @@ func (t *http2Client) handleData(f *http2.DataFrame) {
 			s.mu.Unlock()
 			return
 		}
-		s.state = streamDone
+		s.finish(status.New(codes.Internal, "server closed the stream without sending trailers"))
-		s.statusCode = codes.Internal
-		s.statusDesc = "server closed the stream without sending trailers"
-		close(s.done)
 		s.mu.Unlock()
 		s.write(recvMsg{err: io.EOF})
 	}
@@ -772,18 +853,16 @@ func (t *http2Client) handleRSTStream(f *http2.RSTStreamFrame) {
 		s.mu.Unlock()
 		return
 	}
-	s.state = streamDone
 	if !s.headerDone {
 		close(s.headerChan)
 		s.headerDone = true
 	}
-	s.statusCode, ok = http2ErrConvTab[http2.ErrCode(f.ErrCode)]
+	statusCode, ok := http2ErrConvTab[http2.ErrCode(f.ErrCode)]
 	if !ok {
 		grpclog.Println("transport: http2Client.handleRSTStream found no mapped gRPC status for the received http2 error ", f.ErrCode)
-		s.statusCode = codes.Unknown
+		statusCode = codes.Unknown
 	}
-	s.statusDesc = fmt.Sprintf("stream terminated by RST_STREAM with error code: %d", f.ErrCode)
+	s.finish(status.Newf(statusCode, "stream terminated by RST_STREAM with error code: %d", f.ErrCode))
-	close(s.done)
 	s.mu.Unlock()
 	s.write(recvMsg{err: io.EOF})
 }
@@ -811,6 +890,9 @@ func (t *http2Client) handlePing(f *http2.PingFrame) {
 }
 
 func (t *http2Client) handleGoAway(f *http2.GoAwayFrame) {
+	if f.ErrCode == http2.ErrCodeEnhanceYourCalm {
+		grpclog.Printf("Client received GoAway with http2.ErrCodeEnhanceYourCalm.")
+	}
 	t.mu.Lock()
 	if t.state == reachable || t.state == draining {
 		if f.LastStreamID > 0 && f.LastStreamID%2 != 1 {
@@ -832,6 +914,7 @@ func (t *http2Client) handleGoAway(f *http2.GoAwayFrame) {
 			t.mu.Unlock()
 			return
 		default:
+			t.setGoAwayReason(f)
 		}
 		t.goAwayID = f.LastStreamID
 		close(t.goAway)
@@ -839,6 +922,26 @@ func (t *http2Client) handleGoAway(f *http2.GoAwayFrame) {
 	t.mu.Unlock()
 }
 
+// setGoAwayReason sets the value of t.goAwayReason based
+// on the GoAway frame received.
+// It expects a lock on transport's mutext to be held by
+// the caller.
+func (t *http2Client) setGoAwayReason(f *http2.GoAwayFrame) {
+	t.goAwayReason = NoReason
+	switch f.ErrCode {
+	case http2.ErrCodeEnhanceYourCalm:
+		if string(f.DebugData()) == "too_many_pings" {
+			t.goAwayReason = TooManyPings
+		}
+	}
+}
+
+func (t *http2Client) GetGoAwayReason() GoAwayReason {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	return t.goAwayReason
+}
+
 func (t *http2Client) handleWindowUpdate(f *http2.WindowUpdateFrame) {
 	id := f.Header().StreamID
 	incr := f.Increment
@@ -857,23 +960,41 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 	if !ok {
 		return
 	}
+	s.bytesReceived = true
 	var state decodeState
 	for _, hf := range frame.Fields {
-		state.processHeaderField(hf)
+		if err := state.processHeaderField(hf); err != nil {
-	}
-	if state.err != nil {
 			s.mu.Lock()
 			if !s.headerDone {
 				close(s.headerChan)
 				s.headerDone = true
 			}
 			s.mu.Unlock()
-		s.write(recvMsg{err: state.err})
+			s.write(recvMsg{err: err})
 			// Something wrong. Stops reading even when there is remaining.
 			return
 		}
+	}
 
 	endStream := frame.StreamEnded()
+	var isHeader bool
+	defer func() {
+		if t.statsHandler != nil {
+			if isHeader {
+				inHeader := &stats.InHeader{
+					Client:     true,
+					WireLength: int(frame.Header().Length),
+				}
+				t.statsHandler.HandleRPC(s.clientStatsCtx, inHeader)
+			} else {
+				inTrailer := &stats.InTrailer{
+					Client:     true,
+					WireLength: int(frame.Header().Length),
+				}
+				t.statsHandler.HandleRPC(s.clientStatsCtx, inTrailer)
+			}
+		}
+	}()
 
 	s.mu.Lock()
 	if !endStream {
@@ -885,6 +1006,7 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 		}
 		close(s.headerChan)
 		s.headerDone = true
+		isHeader = true
 	}
 	if !endStream || s.state == streamDone {
 		s.mu.Unlock()
@@ -894,10 +1016,7 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 	if len(state.mdata) > 0 {
 		s.trailer = state.mdata
 	}
-	s.statusCode = state.statusCode
+	s.finish(state.status())
-	s.statusDesc = state.statusDesc
-	close(s.done)
-	s.state = streamDone
 	s.mu.Unlock()
 	s.write(recvMsg{err: io.EOF})
 }
@@ -925,6 +1044,7 @@ func (t *http2Client) reader() {
 		t.notifyError(err)
 		return
 	}
+	atomic.CompareAndSwapUint32(&t.activity, 0, 1)
 	sf, ok := frame.(*http2.SettingsFrame)
 	if !ok {
 		t.notifyError(err)
@@ -935,6 +1055,7 @@ func (t *http2Client) reader() {
 	// loop to keep reading incoming messages on this transport.
 	for {
 		frame, err := t.framer.readFrame()
+		atomic.CompareAndSwapUint32(&t.activity, 0, 1)
 		if err != nil {
 			// Abort an active stream if the http2.Framer returns a
 			// http2.StreamError. This can happen only if the server's response
@@ -986,21 +1107,15 @@ func (t *http2Client) applySettings(ss []http2.Setting) {
 				s.Val = math.MaxInt32
 			}
 			t.mu.Lock()
-			reset := t.streamsQuota != nil
-			if !reset {
-				t.streamsQuota = newQuotaPool(int(s.Val) - len(t.activeStreams))
-			}
 			ms := t.maxStreams
 			t.maxStreams = int(s.Val)
 			t.mu.Unlock()
-			if reset {
+			t.streamsQuota.add(int(s.Val) - ms)
-				t.streamsQuota.reset(int(s.Val) - ms)
-			}
 		case http2.SettingInitialWindowSize:
 			t.mu.Lock()
 			for _, stream := range t.activeStreams {
 				// Adjust the sending quota for each stream.
-				stream.sendQuotaPool.reset(int(s.Val - t.streamSendQuota))
+				stream.sendQuotaPool.add(int(s.Val - t.streamSendQuota))
 			}
 			t.streamSendQuota = s.Val
 			t.mu.Unlock()
@@ -1028,6 +1143,12 @@ func (t *http2Client) controller() {
 						t.framer.writeSettings(true, i.ss...)
 					}
 				case *resetStream:
+					// If the server needs to be to intimated about stream closing,
+					// then we need to make sure the RST_STREAM frame is written to
+					// the wire before the headers of the next stream waiting on
+					// streamQuota. We ensure this by adding to the streamsQuota pool
+					// only after having acquired the writableChan to send RST_STREAM.
+					t.streamsQuota.add(1)
 					t.framer.writeRSTStream(true, i.streamID, i.code)
 				case *flushIO:
 					t.framer.flushWrite()
@@ -1047,6 +1168,61 @@ func (t *http2Client) controller() {
 	}
 }
 
+// keepalive running in a separate goroutune makes sure the connection is alive by sending pings.
+func (t *http2Client) keepalive() {
+	p := &ping{data: [8]byte{}}
+	timer := time.NewTimer(t.kp.Time)
+	for {
+		select {
+		case <-timer.C:
+			if atomic.CompareAndSwapUint32(&t.activity, 1, 0) {
+				timer.Reset(t.kp.Time)
+				continue
+			}
+			// Check if keepalive should go dormant.
+			t.mu.Lock()
+			if len(t.activeStreams) < 1 && !t.kp.PermitWithoutStream {
+				// Make awakenKeepalive writable.
+				<-t.awakenKeepalive
+				t.mu.Unlock()
+				select {
+				case <-t.awakenKeepalive:
+					// If the control gets here a ping has been sent
+					// need to reset the timer with keepalive.Timeout.
+				case <-t.shutdownChan:
+					return
+				}
+			} else {
+				t.mu.Unlock()
+				// Send ping.
+				t.controlBuf.put(p)
+			}
+
+			// By the time control gets here a ping has been sent one way or the other.
+			timer.Reset(t.kp.Timeout)
+			select {
+			case <-timer.C:
+				if atomic.CompareAndSwapUint32(&t.activity, 1, 0) {
+					timer.Reset(t.kp.Time)
+					continue
+				}
+				t.Close()
+				return
+			case <-t.shutdownChan:
+				if !timer.Stop() {
+					<-timer.C
+				}
+				return
+			}
+		case <-t.shutdownChan:
+			if !timer.Stop() {
+				<-timer.C
+			}
+			return
+		}
+	}
+}
+
 func (t *http2Client) Error() <-chan struct{} {
 	return t.errorChan
 }

vendor/google.golang.org/grpc/transport/http2_server.go

@@ -38,18 +38,26 @@ import (
 	"errors"
 	"io"
 	"math"
+	"math/rand"
 	"net"
 	"strconv"
 	"sync"
+	"sync/atomic"
+	"time"
 
+	"github.com/golang/protobuf/proto"
 	"golang.org/x/net/context"
 	"golang.org/x/net/http2"
 	"golang.org/x/net/http2/hpack"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/keepalive"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/peer"
+	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
+	"google.golang.org/grpc/tap"
 )
 
 // ErrIllegalHeaderWrite indicates that setting header is illegal because of
@@ -58,9 +66,13 @@ var ErrIllegalHeaderWrite = errors.New("transport: the stream is done or WriteHe
 
 // http2Server implements the ServerTransport interface with HTTP2.
 type http2Server struct {
+	ctx         context.Context
 	conn        net.Conn
+	remoteAddr  net.Addr
+	localAddr   net.Addr
 	maxStreamID uint32               // max stream ID ever seen
 	authInfo    credentials.AuthInfo // auth info about the connection
+	inTapHandle tap.ServerInHandle
 	// writableChan synchronizes write access to the transport.
 	// A writer acquires the write lock by receiving a value on writableChan
 	// and releases it by sending on writableChan.
@@ -82,21 +94,46 @@ type http2Server struct {
 	// sendQuotaPool provides flow control to outbound message.
 	sendQuotaPool *quotaPool
 
+	stats stats.Handler
+
+	// Flag to keep track of reading activity on transport.
+	// 1 is true and 0 is false.
+	activity uint32 // Accessed atomically.
+	// Keepalive and max-age parameters for the server.
+	kp keepalive.ServerParameters
+
+	// Keepalive enforcement policy.
+	kep keepalive.EnforcementPolicy
+	// The time instance last ping was received.
+	lastPingAt time.Time
+	// Number of times the client has violated keepalive ping policy so far.
+	pingStrikes uint8
+	// Flag to signify that number of ping strikes should be reset to 0.
+	// This is set whenever data or header frames are sent.
+	// 1 means yes.
+	resetPingStrikes uint32 // Accessed atomically.
+
 	mu            sync.Mutex // guard the following
 	state         transportState
 	activeStreams map[uint32]*Stream
 	// the per-stream outbound flow control window size set by the peer.
 	streamSendQuota uint32
+	// idle is the time instant when the connection went idle.
+	// This is either the begining of the connection or when the number of
+	// RPCs go down to 0.
+	// When the connection is busy, this value is set to 0.
+	idle time.Time
 }
 
 // newHTTP2Server constructs a ServerTransport based on HTTP2. ConnectionError is
 // returned if something goes wrong.
-func newHTTP2Server(conn net.Conn, maxStreams uint32, authInfo credentials.AuthInfo) (_ ServerTransport, err error) {
+func newHTTP2Server(conn net.Conn, config *ServerConfig) (_ ServerTransport, err error) {
 	framer := newFramer(conn)
 	// Send initial settings as connection preface to client.
 	var settings []http2.Setting
 	// TODO(zhaoq): Have a better way to signal "no limit" because 0 is
 	// permitted in the HTTP2 spec.
+	maxStreams := config.MaxStreams
 	if maxStreams == 0 {
 		maxStreams = math.MaxUint32
 	} else {
@@ -119,14 +156,40 @@ func newHTTP2Server(conn net.Conn, maxStreams uint32, authInfo credentials.AuthI
 			return nil, connectionErrorf(true, err, "transport: %v", err)
 		}
 	}
+	kp := config.KeepaliveParams
+	if kp.MaxConnectionIdle == 0 {
+		kp.MaxConnectionIdle = defaultMaxConnectionIdle
+	}
+	if kp.MaxConnectionAge == 0 {
+		kp.MaxConnectionAge = defaultMaxConnectionAge
+	}
+	// Add a jitter to MaxConnectionAge.
+	kp.MaxConnectionAge += getJitter(kp.MaxConnectionAge)
+	if kp.MaxConnectionAgeGrace == 0 {
+		kp.MaxConnectionAgeGrace = defaultMaxConnectionAgeGrace
+	}
+	if kp.Time == 0 {
+		kp.Time = defaultServerKeepaliveTime
+	}
+	if kp.Timeout == 0 {
+		kp.Timeout = defaultServerKeepaliveTimeout
+	}
+	kep := config.KeepalivePolicy
+	if kep.MinTime == 0 {
+		kep.MinTime = defaultKeepalivePolicyMinTime
+	}
 	var buf bytes.Buffer
 	t := &http2Server{
+		ctx:             context.Background(),
 		conn:            conn,
-		authInfo:        authInfo,
+		remoteAddr:      conn.RemoteAddr(),
+		localAddr:       conn.LocalAddr(),
+		authInfo:        config.AuthInfo,
 		framer:          framer,
 		hBuf:            &buf,
 		hEnc:            hpack.NewEncoder(&buf),
 		maxStreams:      maxStreams,
+		inTapHandle:     config.InTapHandle,
 		controlBuf:      newRecvBuffer(),
 		fc:              &inFlow{limit: initialConnWindowSize},
 		sendQuotaPool:   newQuotaPool(defaultWindowSize),
@@ -135,14 +198,27 @@ func newHTTP2Server(conn net.Conn, maxStreams uint32, authInfo credentials.AuthI
 		shutdownChan:    make(chan struct{}),
 		activeStreams:   make(map[uint32]*Stream),
 		streamSendQuota: defaultWindowSize,
+		stats:           config.StatsHandler,
+		kp:              kp,
+		idle:            time.Now(),
+		kep:             kep,
+	}
+	if t.stats != nil {
+		t.ctx = t.stats.TagConn(t.ctx, &stats.ConnTagInfo{
+			RemoteAddr: t.remoteAddr,
+			LocalAddr:  t.localAddr,
+		})
+		connBegin := &stats.ConnBegin{}
+		t.stats.HandleConn(t.ctx, connBegin)
 	}
 	go t.controller()
+	go t.keepalive()
 	t.writableChan <- 0
 	return t, nil
 }
 
 // operateHeader takes action on the decoded headers.
-func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(*Stream)) (close bool) {
+func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(*Stream), traceCtx func(context.Context, string) context.Context) (close bool) {
 	buf := newRecvBuffer()
 	s := &Stream{
 		id:  frame.Header().StreamID,
@@ -153,14 +229,13 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 
 	var state decodeState
 	for _, hf := range frame.Fields {
-		state.processHeaderField(hf)
+		if err := state.processHeaderField(hf); err != nil {
-	}
-	if err := state.err; err != nil {
 			if se, ok := err.(StreamError); ok {
 				t.controlBuf.put(&resetStream{s.id, statusCodeConvTab[se.Code]})
 			}
 			return
 		}
+	}
 
 	if frame.StreamEnded() {
 		// s is just created by the caller. No lock needed.
@@ -168,12 +243,12 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 	}
 	s.recvCompress = state.encoding
 	if state.timeoutSet {
-		s.ctx, s.cancel = context.WithTimeout(context.TODO(), state.timeout)
+		s.ctx, s.cancel = context.WithTimeout(t.ctx, state.timeout)
 	} else {
-		s.ctx, s.cancel = context.WithCancel(context.TODO())
+		s.ctx, s.cancel = context.WithCancel(t.ctx)
 	}
 	pr := &peer.Peer{
-		Addr: t.conn.RemoteAddr(),
+		Addr: t.remoteAddr,
 	}
 	// Attach Auth info if there is any.
 	if t.authInfo != nil {
@@ -186,7 +261,7 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 	s.ctx = newContextWithStream(s.ctx, s)
 	// Attach the received metadata to the context.
 	if len(state.mdata) > 0 {
-		s.ctx = metadata.NewContext(s.ctx, state.mdata)
+		s.ctx = metadata.NewIncomingContext(s.ctx, state.mdata)
 	}
 
 	s.dec = &recvBufferReader{
@@ -195,6 +270,18 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 	}
 	s.recvCompress = state.encoding
 	s.method = state.method
+	if t.inTapHandle != nil {
+		var err error
+		info := &tap.Info{
+			FullMethodName: state.method,
+		}
+		s.ctx, err = t.inTapHandle(s.ctx, info)
+		if err != nil {
+			// TODO: Log the real error.
+			t.controlBuf.put(&resetStream{s.id, http2.ErrCodeRefusedStream})
+			return
+		}
+	}
 	t.mu.Lock()
 	if t.state != reachable {
 		t.mu.Unlock()
@@ -214,17 +301,33 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 	t.maxStreamID = s.id
 	s.sendQuotaPool = newQuotaPool(int(t.streamSendQuota))
 	t.activeStreams[s.id] = s
+	if len(t.activeStreams) == 1 {
+		t.idle = time.Time{}
+	}
 	t.mu.Unlock()
 	s.windowHandler = func(n int) {
 		t.updateWindow(s, uint32(n))
 	}
+	s.ctx = traceCtx(s.ctx, s.method)
+	if t.stats != nil {
+		s.ctx = t.stats.TagRPC(s.ctx, &stats.RPCTagInfo{FullMethodName: s.method})
+		inHeader := &stats.InHeader{
+			FullMethod:  s.method,
+			RemoteAddr:  t.remoteAddr,
+			LocalAddr:   t.localAddr,
+			Compression: s.recvCompress,
+			WireLength:  int(frame.Header().Length),
+		}
+		t.stats.HandleRPC(s.ctx, inHeader)
+	}
 	handle(s)
 	return
 }
 
 // HandleStreams receives incoming streams using the given handler. This is
 // typically run in a separate goroutine.
-func (t *http2Server) HandleStreams(handle func(*Stream)) {
+// traceCtx attaches trace to ctx and returns the new context.
+func (t *http2Server) HandleStreams(handle func(*Stream), traceCtx func(context.Context, string) context.Context) {
 	// Check the validity of client preface.
 	preface := make([]byte, len(clientPreface))
 	if _, err := io.ReadFull(t.conn, preface); err != nil {
@@ -248,6 +351,7 @@ func (t *http2Server) HandleStreams(handle func(*Stream)) {
 		t.Close()
 		return
 	}
+	atomic.StoreUint32(&t.activity, 1)
 	sf, ok := frame.(*http2.SettingsFrame)
 	if !ok {
 		grpclog.Printf("transport: http2Server.HandleStreams saw invalid preface type %T from client", frame)
@@ -258,6 +362,7 @@ func (t *http2Server) HandleStreams(handle func(*Stream)) {
 
 	for {
 		frame, err := t.framer.readFrame()
+		atomic.StoreUint32(&t.activity, 1)
 		if err != nil {
 			if se, ok := err.(http2.StreamError); ok {
 				t.mu.Lock()
@@ -279,7 +384,7 @@ func (t *http2Server) HandleStreams(handle func(*Stream)) {
 		}
 		switch frame := frame.(type) {
 		case *http2.MetaHeadersFrame:
-			if t.operateHeaders(frame, handle) {
+			if t.operateHeaders(frame, handle, traceCtx) {
 				t.Close()
 				break
 			}
@@ -334,7 +439,7 @@ func (t *http2Server) updateWindow(s *Stream, n uint32) {
 }
 
 func (t *http2Server) handleData(f *http2.DataFrame) {
-	size := len(f.Data())
+	size := f.Header().Length
 	if err := t.fc.onData(uint32(size)); err != nil {
 		grpclog.Printf("transport: http2Server %v", err)
 		t.Close()
@@ -349,6 +454,11 @@ func (t *http2Server) handleData(f *http2.DataFrame) {
 		return
 	}
 	if size > 0 {
+		if f.Header().Flags.Has(http2.FlagDataPadded) {
+			if w := t.fc.onRead(uint32(size) - uint32(len(f.Data()))); w > 0 {
+				t.controlBuf.put(&windowUpdate{0, w})
+			}
+		}
 		s.mu.Lock()
 		if s.state == streamDone {
 			s.mu.Unlock()
@@ -364,14 +474,21 @@ func (t *http2Server) handleData(f *http2.DataFrame) {
 			t.controlBuf.put(&resetStream{s.id, http2.ErrCodeFlowControl})
 			return
 		}
+		if f.Header().Flags.Has(http2.FlagDataPadded) {
+			if w := s.fc.onRead(uint32(size) - uint32(len(f.Data()))); w > 0 {
+				t.controlBuf.put(&windowUpdate{s.id, w})
+			}
+		}
 		s.mu.Unlock()
 		// TODO(bradfitz, zhaoq): A copy is required here because there is no
 		// guarantee f.Data() is consumed before the arrival of next frame.
 		// Can this copy be eliminated?
-		data := make([]byte, size)
+		if len(f.Data()) > 0 {
+			data := make([]byte, len(f.Data()))
 			copy(data, f.Data())
 			s.write(recvMsg{data: data})
 		}
+	}
 	if f.Header().Flags.Has(http2.FlagDataEndStream) {
 		// Received the end of stream from the client.
 		s.mu.Lock()
@@ -404,6 +521,11 @@ func (t *http2Server) handleSettings(f *http2.SettingsFrame) {
 	t.controlBuf.put(&settings{ack: true, ss: ss})
 }
 
+const (
+	maxPingStrikes     = 2
+	defaultPingTimeout = 2 * time.Hour
+)
+
 func (t *http2Server) handlePing(f *http2.PingFrame) {
 	if f.IsAck() { // Do nothing.
 		return
@@ -411,6 +533,38 @@ func (t *http2Server) handlePing(f *http2.PingFrame) {
 	pingAck := &ping{ack: true}
 	copy(pingAck.data[:], f.Data[:])
 	t.controlBuf.put(pingAck)
+
+	now := time.Now()
+	defer func() {
+		t.lastPingAt = now
+	}()
+	// A reset ping strikes means that we don't need to check for policy
+	// violation for this ping and the pingStrikes counter should be set
+	// to 0.
+	if atomic.CompareAndSwapUint32(&t.resetPingStrikes, 1, 0) {
+		t.pingStrikes = 0
+		return
+	}
+	t.mu.Lock()
+	ns := len(t.activeStreams)
+	t.mu.Unlock()
+	if ns < 1 && !t.kep.PermitWithoutStream {
+		// Keepalive shouldn't be active thus, this new ping should
+		// have come after atleast defaultPingTimeout.
+		if t.lastPingAt.Add(defaultPingTimeout).After(now) {
+			t.pingStrikes++
+		}
+	} else {
+		// Check if keepalive policy is respected.
+		if t.lastPingAt.Add(t.kep.MinTime).After(now) {
+			t.pingStrikes++
+		}
+	}
+
+	if t.pingStrikes > maxPingStrikes {
+		// Send goaway and close the connection.
+		t.controlBuf.put(&goAway{code: http2.ErrCodeEnhanceYourCalm, debugData: []byte("too_many_pings")})
+	}
 }
 
 func (t *http2Server) handleWindowUpdate(f *http2.WindowUpdateFrame) {
@@ -429,6 +583,13 @@ func (t *http2Server) writeHeaders(s *Stream, b *bytes.Buffer, endStream bool) e
 	first := true
 	endHeaders := false
 	var err error
+	defer func() {
+		if err == nil {
+			// Reset ping strikes when seding headers since that might cause the
+			// peer to send ping.
+			atomic.StoreUint32(&t.resetPingStrikes, 1)
+		}
+	}()
 	// Sends the headers in a single batch.
 	for !endHeaders {
 		size := t.hBuf.Len()
@@ -483,18 +644,25 @@ func (t *http2Server) WriteHeader(s *Stream, md metadata.MD) error {
 	if s.sendCompress != "" {
 		t.hEnc.WriteField(hpack.HeaderField{Name: "grpc-encoding", Value: s.sendCompress})
 	}
-	for k, v := range md {
+	for k, vv := range md {
 		if isReservedHeader(k) {
 			// Clients don't tolerate reading restricted headers after some non restricted ones were sent.
 			continue
 		}
-		for _, entry := range v {
+		for _, v := range vv {
-			t.hEnc.WriteField(hpack.HeaderField{Name: k, Value: entry})
+			t.hEnc.WriteField(hpack.HeaderField{Name: k, Value: encodeMetadataHeader(k, v)})
 		}
 	}
+	bufLen := t.hBuf.Len()
 	if err := t.writeHeaders(s, t.hBuf, false); err != nil {
 		return err
 	}
+	if t.stats != nil {
+		outHeader := &stats.OutHeader{
+			WireLength: bufLen,
+		}
+		t.stats.HandleRPC(s.Context(), outHeader)
+	}
 	t.writableChan <- 0
 	return nil
 }
@@ -503,7 +671,7 @@ func (t *http2Server) WriteHeader(s *Stream, md metadata.MD) error {
 // There is no further I/O operations being able to perform on this stream.
 // TODO(zhaoq): Now it indicates the end of entire stream. Revisit if early
 // OK is adopted.
-func (t *http2Server) WriteStatus(s *Stream, statusCode codes.Code, statusDesc string) error {
+func (t *http2Server) WriteStatus(s *Stream, st *status.Status) error {
 	var headersSent, hasHeader bool
 	s.mu.Lock()
 	if s.state == streamDone {
@@ -534,23 +702,41 @@ func (t *http2Server) WriteStatus(s *Stream, statusCode codes.Code, statusDesc s
 	t.hEnc.WriteField(
 		hpack.HeaderField{
 			Name:  "grpc-status",
-			Value: strconv.Itoa(int(statusCode)),
+			Value: strconv.Itoa(int(st.Code())),
 		})
-	t.hEnc.WriteField(hpack.HeaderField{Name: "grpc-message", Value: encodeGrpcMessage(statusDesc)})
+	t.hEnc.WriteField(hpack.HeaderField{Name: "grpc-message", Value: encodeGrpcMessage(st.Message())})
+
+	if p := st.Proto(); p != nil && len(p.Details) > 0 {
+		stBytes, err := proto.Marshal(p)
+		if err != nil {
+			// TODO: return error instead, when callers are able to handle it.
+			panic(err)
+		}
+
+		t.hEnc.WriteField(hpack.HeaderField{Name: "grpc-status-details-bin", Value: encodeBinHeader(stBytes)})
+	}
+
 	// Attach the trailer metadata.
-	for k, v := range s.trailer {
+	for k, vv := range s.trailer {
 		// Clients don't tolerate reading restricted headers after some non restricted ones were sent.
 		if isReservedHeader(k) {
 			continue
 		}
-		for _, entry := range v {
+		for _, v := range vv {
-			t.hEnc.WriteField(hpack.HeaderField{Name: k, Value: entry})
+			t.hEnc.WriteField(hpack.HeaderField{Name: k, Value: encodeMetadataHeader(k, v)})
 		}
 	}
+	bufLen := t.hBuf.Len()
 	if err := t.writeHeaders(s, t.hBuf, true); err != nil {
 		t.Close()
 		return err
 	}
+	if t.stats != nil {
+		outTrailer := &stats.OutTrailer{
+			WireLength: bufLen,
+		}
+		t.stats.HandleRPC(s.Context(), outTrailer)
+	}
 	t.closeStream(s)
 	t.writableChan <- 0
 	return nil
@@ -558,7 +744,7 @@ func (t *http2Server) WriteStatus(s *Stream, statusCode codes.Code, statusDesc s
 
 // Write converts the data into HTTP2 data frame and sends it out. Non-nil error
 // is returns if it fails (e.g., framing error, transport error).
-func (t *http2Server) Write(s *Stream, data []byte, opts *Options) error {
+func (t *http2Server) Write(s *Stream, data []byte, opts *Options) (err error) {
 	// TODO(zhaoq): Support multi-writers for a single stream.
 	var writeHeaderFrame bool
 	s.mu.Lock()
@@ -573,25 +759,27 @@ func (t *http2Server) Write(s *Stream, data []byte, opts *Options) error {
 	if writeHeaderFrame {
 		t.WriteHeader(s, nil)
 	}
+	defer func() {
+		if err == nil {
+			// Reset ping strikes when sending data since this might cause
+			// the peer to send ping.
+			atomic.StoreUint32(&t.resetPingStrikes, 1)
+		}
+	}()
 	r := bytes.NewBuffer(data)
 	for {
 		if r.Len() == 0 {
 			return nil
 		}
 		size := http2MaxFrameLen
-		s.sendQuotaPool.add(0)
 		// Wait until the stream has some quota to send the data.
 		sq, err := wait(s.ctx, nil, nil, t.shutdownChan, s.sendQuotaPool.acquire())
 		if err != nil {
 			return err
 		}
-		t.sendQuotaPool.add(0)
 		// Wait until the transport has some quota to send the data.
 		tq, err := wait(s.ctx, nil, nil, t.shutdownChan, t.sendQuotaPool.acquire())
 		if err != nil {
-			if _, ok := err.(StreamError); ok {
-				t.sendQuotaPool.cancel()
-			}
 			return err
 		}
 		if sq < size {
@@ -659,7 +847,7 @@ func (t *http2Server) applySettings(ss []http2.Setting) {
 			t.mu.Lock()
 			defer t.mu.Unlock()
 			for _, stream := range t.activeStreams {
-				stream.sendQuotaPool.reset(int(s.Val - t.streamSendQuota))
+				stream.sendQuotaPool.add(int(s.Val - t.streamSendQuota))
 			}
 			t.streamSendQuota = s.Val
 		}
@@ -667,6 +855,91 @@ func (t *http2Server) applySettings(ss []http2.Setting) {
 	}
 }
 
+// keepalive running in a separate goroutine does the following:
+// 1. Gracefully closes an idle connection after a duration of keepalive.MaxConnectionIdle.
+// 2. Gracefully closes any connection after a duration of keepalive.MaxConnectionAge.
+// 3. Forcibly closes a connection after an additive period of keepalive.MaxConnectionAgeGrace over keepalive.MaxConnectionAge.
+// 4. Makes sure a connection is alive by sending pings with a frequency of keepalive.Time and closes a non-resposive connection
+// after an additional duration of keepalive.Timeout.
+func (t *http2Server) keepalive() {
+	p := &ping{}
+	var pingSent bool
+	maxIdle := time.NewTimer(t.kp.MaxConnectionIdle)
+	maxAge := time.NewTimer(t.kp.MaxConnectionAge)
+	keepalive := time.NewTimer(t.kp.Time)
+	// NOTE: All exit paths of this function should reset their
+	// respecitve timers. A failure to do so will cause the
+	// following clean-up to deadlock and eventually leak.
+	defer func() {
+		if !maxIdle.Stop() {
+			<-maxIdle.C
+		}
+		if !maxAge.Stop() {
+			<-maxAge.C
+		}
+		if !keepalive.Stop() {
+			<-keepalive.C
+		}
+	}()
+	for {
+		select {
+		case <-maxIdle.C:
+			t.mu.Lock()
+			idle := t.idle
+			if idle.IsZero() { // The connection is non-idle.
+				t.mu.Unlock()
+				maxIdle.Reset(t.kp.MaxConnectionIdle)
+				continue
+			}
+			val := t.kp.MaxConnectionIdle - time.Since(idle)
+			if val <= 0 {
+				// The connection has been idle for a duration of keepalive.MaxConnectionIdle or more.
+				// Gracefully close the connection.
+				t.state = draining
+				t.mu.Unlock()
+				t.Drain()
+				// Reseting the timer so that the clean-up doesn't deadlock.
+				maxIdle.Reset(infinity)
+				return
+			}
+			t.mu.Unlock()
+			maxIdle.Reset(val)
+		case <-maxAge.C:
+			t.mu.Lock()
+			t.state = draining
+			t.mu.Unlock()
+			t.Drain()
+			maxAge.Reset(t.kp.MaxConnectionAgeGrace)
+			select {
+			case <-maxAge.C:
+				// Close the connection after grace period.
+				t.Close()
+				// Reseting the timer so that the clean-up doesn't deadlock.
+				maxAge.Reset(infinity)
+			case <-t.shutdownChan:
+			}
+			return
+		case <-keepalive.C:
+			if atomic.CompareAndSwapUint32(&t.activity, 1, 0) {
+				pingSent = false
+				keepalive.Reset(t.kp.Time)
+				continue
+			}
+			if pingSent {
+				t.Close()
+				// Reseting the timer so that the clean-up doesn't deadlock.
+				keepalive.Reset(infinity)
+				return
+			}
+			pingSent = true
+			t.controlBuf.put(p)
+			keepalive.Reset(t.kp.Timeout)
+		case <-t.shutdownChan:
+			return
+		}
+	}
+}
+
 // controller running in a separate goroutine takes charge of sending control
 // frames (e.g., window update, reset stream, setting, etc.) to the server.
 func (t *http2Server) controller() {
@@ -698,7 +971,10 @@ func (t *http2Server) controller() {
 					sid := t.maxStreamID
 					t.state = draining
 					t.mu.Unlock()
-					t.framer.writeGoAway(true, sid, http2.ErrCodeNo, nil)
+					t.framer.writeGoAway(true, sid, i.code, i.debugData)
+					if i.code == http2.ErrCodeEnhanceYourCalm {
+						t.Close()
+					}
 				case *flushIO:
 					t.framer.flushWrite()
 				case *ping:
@@ -736,6 +1012,10 @@ func (t *http2Server) Close() (err error) {
 	for _, s := range streams {
 		s.cancel()
 	}
+	if t.stats != nil {
+		connEnd := &stats.ConnEnd{}
+		t.stats.HandleConn(t.ctx, connEnd)
+	}
 	return
 }
 
@@ -744,6 +1024,9 @@ func (t *http2Server) Close() (err error) {
 func (t *http2Server) closeStream(s *Stream) {
 	t.mu.Lock()
 	delete(t.activeStreams, s.id)
+	if len(t.activeStreams) == 0 {
+		t.idle = time.Now()
+	}
 	if t.state == draining && len(t.activeStreams) == 0 {
 		defer t.Close()
 	}
@@ -767,9 +1050,21 @@ func (t *http2Server) closeStream(s *Stream) {
 }
 
 func (t *http2Server) RemoteAddr() net.Addr {
-	return t.conn.RemoteAddr()
+	return t.remoteAddr
 }
 
 func (t *http2Server) Drain() {
-	t.controlBuf.put(&goAway{})
+	t.controlBuf.put(&goAway{code: http2.ErrCodeNo})
+}
+
+var rgen = rand.New(rand.NewSource(time.Now().UnixNano()))
+
+func getJitter(v time.Duration) time.Duration {
+	if v == infinity {
+		return 0
+	}
+	// Generate a jitter between +/- 10% of the value.
+	r := int64(v / 10)
+	j := rgen.Int63n(2*r) - r
+	return time.Duration(j)
 }

vendor/google.golang.org/grpc/transport/http_util.go

@@ -36,6 +36,7 @@ package transport
 import (
 	"bufio"
 	"bytes"
+	"encoding/base64"
 	"fmt"
 	"io"
 	"net"
@@ -44,16 +45,16 @@ import (
 	"sync/atomic"
 	"time"
 
+	"github.com/golang/protobuf/proto"
 	"golang.org/x/net/http2"
 	"golang.org/x/net/http2/hpack"
+	spb "google.golang.org/genproto/googleapis/rpc/status"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/grpclog"
-	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/status"
 )
 
 const (
-	// The primary user agent
-	primaryUA = "grpc-go/1.0"
 	// http2MaxFrameLen specifies the max length of a HTTP2 frame.
 	http2MaxFrameLen = 16384 // 16KB frame
 	// http://http2.github.io/http2-spec/#SettingValues
@@ -92,13 +93,15 @@ var (
 // Records the states during HPACK decoding. Must be reset once the
 // decoding of the entire headers are finished.
 type decodeState struct {
-	err error // first error encountered decoding
-
 	encoding string
-	// statusCode caches the stream status received from the trailer
+	// statusGen caches the stream status received from the trailer the server
-	// the server sent. Client side only.
+	// sent.  Client side only.  Do not access directly.  After all trailers are
-	statusCode codes.Code
+	// parsed, use the status method to retrieve the status.
-	statusDesc string
+	statusGen *status.Status
+	// rawStatusCode and rawStatusMsg are set from the raw trailer fields and are not
+	// intended for direct access outside of parsing.
+	rawStatusCode int32
+	rawStatusMsg  string
 	// Server side only fields.
 	timeoutSet bool
 	timeout    time.Duration
@@ -121,6 +124,7 @@ func isReservedHeader(hdr string) bool {
 		"grpc-message",
 		"grpc-status",
 		"grpc-timeout",
+		"grpc-status-details-bin",
 		"te":
 		return true
 	default:
@@ -139,12 +143,6 @@ func isWhitelistedPseudoHeader(hdr string) bool {
 	}
 }
 
-func (d *decodeState) setErr(err error) {
-	if d.err == nil {
-		d.err = err
-	}
-}
-
 func validContentType(t string) bool {
 	e := "application/grpc"
 	if !strings.HasPrefix(t, e) {
@@ -158,56 +156,91 @@ func validContentType(t string) bool {
 	return true
 }
 
-func (d *decodeState) processHeaderField(f hpack.HeaderField) {
+func (d *decodeState) status() *status.Status {
+	if d.statusGen == nil {
+		// No status-details were provided; generate status using code/msg.
+		d.statusGen = status.New(codes.Code(d.rawStatusCode), d.rawStatusMsg)
+	}
+	return d.statusGen
+}
+
+const binHdrSuffix = "-bin"
+
+func encodeBinHeader(v []byte) string {
+	return base64.RawStdEncoding.EncodeToString(v)
+}
+
+func decodeBinHeader(v string) ([]byte, error) {
+	if len(v)%4 == 0 {
+		// Input was padded, or padding was not necessary.
+		return base64.StdEncoding.DecodeString(v)
+	}
+	return base64.RawStdEncoding.DecodeString(v)
+}
+
+func encodeMetadataHeader(k, v string) string {
+	if strings.HasSuffix(k, binHdrSuffix) {
+		return encodeBinHeader(([]byte)(v))
+	}
+	return v
+}
+
+func decodeMetadataHeader(k, v string) (string, error) {
+	if strings.HasSuffix(k, binHdrSuffix) {
+		b, err := decodeBinHeader(v)
+		return string(b), err
+	}
+	return v, nil
+}
+
+func (d *decodeState) processHeaderField(f hpack.HeaderField) error {
 	switch f.Name {
 	case "content-type":
 		if !validContentType(f.Value) {
-			d.setErr(streamErrorf(codes.FailedPrecondition, "transport: received the unexpected content-type %q", f.Value))
+			return streamErrorf(codes.FailedPrecondition, "transport: received the unexpected content-type %q", f.Value)
-			return
 		}
 	case "grpc-encoding":
 		d.encoding = f.Value
 	case "grpc-status":
 		code, err := strconv.Atoi(f.Value)
 		if err != nil {
-			d.setErr(streamErrorf(codes.Internal, "transport: malformed grpc-status: %v", err))
+			return streamErrorf(codes.Internal, "transport: malformed grpc-status: %v", err)
-			return
 		}
-		d.statusCode = codes.Code(code)
+		d.rawStatusCode = int32(code)
 	case "grpc-message":
-		d.statusDesc = decodeGrpcMessage(f.Value)
+		d.rawStatusMsg = decodeGrpcMessage(f.Value)
+	case "grpc-status-details-bin":
+		v, err := decodeBinHeader(f.Value)
+		if err != nil {
+			return streamErrorf(codes.Internal, "transport: malformed grpc-status-details-bin: %v", err)
+		}
+		s := &spb.Status{}
+		if err := proto.Unmarshal(v, s); err != nil {
+			return streamErrorf(codes.Internal, "transport: malformed grpc-status-details-bin: %v", err)
+		}
+		d.statusGen = status.FromProto(s)
 	case "grpc-timeout":
 		d.timeoutSet = true
 		var err error
-		d.timeout, err = decodeTimeout(f.Value)
+		if d.timeout, err = decodeTimeout(f.Value); err != nil {
-		if err != nil {
+			return streamErrorf(codes.Internal, "transport: malformed time-out: %v", err)
-			d.setErr(streamErrorf(codes.Internal, "transport: malformed time-out: %v", err))
-			return
 		}
 	case ":path":
 		d.method = f.Value
 	default:
 		if !isReservedHeader(f.Name) || isWhitelistedPseudoHeader(f.Name) {
-			if f.Name == "user-agent" {
-				i := strings.LastIndex(f.Value, " ")
-				if i == -1 {
-					// There is no application user agent string being set.
-					return
-				}
-				// Extract the application user agent string.
-				f.Value = f.Value[:i]
-			}
 			if d.mdata == nil {
 				d.mdata = make(map[string][]string)
 			}
-			k, v, err := metadata.DecodeKeyValue(f.Name, f.Value)
+			v, err := decodeMetadataHeader(f.Name, f.Value)
 			if err != nil {
 				grpclog.Printf("Failed to decode (%q, %q): %v", f.Name, f.Value, err)
-				return
+				return nil
 			}
-			d.mdata[k] = append(d.mdata[k], v)
+			d.mdata[f.Name] = append(d.mdata[f.Name], v)
 		}
 	}
+	return nil
 }
 
 type timeoutUnit uint8
@@ -379,6 +412,9 @@ func newFramer(conn net.Conn) *framer {
 		writer: bufio.NewWriterSize(conn, http2IOBufSize),
 	}
 	f.fr = http2.NewFramer(f.writer, f.reader)
+	// Opt-in to Frame reuse API on framer to reduce garbage.
+	// Frames aren't safe to read from after a subsequent call to ReadFrame.
+	f.fr.SetReuseFrames()
 	f.fr.ReadMetaHeaders = hpack.NewDecoder(http2InitHeaderTableSize, nil)
 	return f
 }

vendor/google.golang.org/grpc/transport/transport.go

@@ -45,10 +45,14 @@ import (
 	"sync"
 
 	"golang.org/x/net/context"
-	"golang.org/x/net/trace"
+	"golang.org/x/net/http2"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials"
+	"google.golang.org/grpc/keepalive"
 	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
+	"google.golang.org/grpc/tap"
 )
 
 // recvMsg represents the received msg from the transport. All transport
@@ -167,6 +171,11 @@ type Stream struct {
 	id uint32
 	// nil for client side Stream.
 	st ServerTransport
+	// clientStatsCtx keeps the user context for stats handling.
+	// It's only valid on client side. Server side stats context is same as s.ctx.
+	// All client side stats collection should use the clientStatsCtx (instead of the stream context)
+	// so that all the generated stats for a particular RPC can be associated in the processing phase.
+	clientStatsCtx context.Context
 	// ctx is the associated context of the stream.
 	ctx context.Context
 	// cancel is always nil for client side Stream.
@@ -204,9 +213,17 @@ type Stream struct {
 	// true iff headerChan is closed. Used to avoid closing headerChan
 	// multiple times.
 	headerDone bool
-	// the status received from the server.
+	// the status error received from the server.
-	statusCode codes.Code
+	status *status.Status
-	statusDesc string
+	// rstStream indicates whether a RST_STREAM frame needs to be sent
+	// to the server to signify that this stream is closing.
+	rstStream bool
+	// rstError is the error that needs to be sent along with the RST_STREAM frame.
+	rstError http2.ErrCode
+	// bytesSent and bytesReceived indicates whether any bytes have been sent or
+	// received on this stream.
+	bytesSent     bool
+	bytesReceived bool
 }
 
 // RecvCompress returns the compression algorithm applied to the inbound
@@ -266,24 +283,14 @@ func (s *Stream) Context() context.Context {
 	return s.ctx
 }
 
-// TraceContext recreates the context of s with a trace.Trace.
-func (s *Stream) TraceContext(tr trace.Trace) {
-	s.ctx = trace.NewContext(s.ctx, tr)
-}
-
 // Method returns the method for the stream.
 func (s *Stream) Method() string {
 	return s.method
 }
 
-// StatusCode returns statusCode received from the server.
+// Status returns the status received from the server.
-func (s *Stream) StatusCode() codes.Code {
+func (s *Stream) Status() *status.Status {
-	return s.statusCode
+	return s.status
-}
-
-// StatusDesc returns statusDesc received from the server.
-func (s *Stream) StatusDesc() string {
-	return s.statusDesc
 }
 
 // SetHeader sets the header metadata. This can be called multiple times.
@@ -330,6 +337,34 @@ func (s *Stream) Read(p []byte) (n int, err error) {
 	return
 }
 
+// finish sets the stream's state and status, and closes the done channel.
+// s.mu must be held by the caller.  st must always be non-nil.
+func (s *Stream) finish(st *status.Status) {
+	s.status = st
+	s.state = streamDone
+	close(s.done)
+}
+
+// BytesSent indicates whether any bytes have been sent on this stream.
+func (s *Stream) BytesSent() bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.bytesSent
+}
+
+// BytesReceived indicates whether any bytes have been received on this stream.
+func (s *Stream) BytesReceived() bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.bytesReceived
+}
+
+// GoString is implemented by Stream so context.String() won't
+// race when printing %#v.
+func (s *Stream) GoString() string {
+	return fmt.Sprintf("<stream: %p, %v>", s, s.method)
+}
+
 // The key to save transport.Stream in the context.
 type streamKey struct{}
 
@@ -355,22 +390,41 @@ const (
 	draining
 )
 
+// ServerConfig consists of all the configurations to establish a server transport.
+type ServerConfig struct {
+	MaxStreams      uint32
+	AuthInfo        credentials.AuthInfo
+	InTapHandle     tap.ServerInHandle
+	StatsHandler    stats.Handler
+	KeepaliveParams keepalive.ServerParameters
+	KeepalivePolicy keepalive.EnforcementPolicy
+}
+
 // NewServerTransport creates a ServerTransport with conn or non-nil error
 // if it fails.
-func NewServerTransport(protocol string, conn net.Conn, maxStreams uint32, authInfo credentials.AuthInfo) (ServerTransport, error) {
+func NewServerTransport(protocol string, conn net.Conn, config *ServerConfig) (ServerTransport, error) {
-	return newHTTP2Server(conn, maxStreams, authInfo)
+	return newHTTP2Server(conn, config)
 }
 
 // ConnectOptions covers all relevant options for communicating with the server.
 type ConnectOptions struct {
 	// UserAgent is the application user agent.
 	UserAgent string
+	// Authority is the :authority pseudo-header to use. This field has no effect if
+	// TransportCredentials is set.
+	Authority string
 	// Dialer specifies how to dial a network address.
 	Dialer func(context.Context, string) (net.Conn, error)
+	// FailOnNonTempDialError specifies if gRPC fails on non-temporary dial errors.
+	FailOnNonTempDialError bool
 	// PerRPCCredentials stores the PerRPCCredentials required to issue RPCs.
 	PerRPCCredentials []credentials.PerRPCCredentials
 	// TransportCredentials stores the Authenticator required to setup a client connection.
 	TransportCredentials credentials.TransportCredentials
+	// KeepaliveParams stores the keepalive parameters.
+	KeepaliveParams keepalive.ClientParameters
+	// StatsHandler stores the handler for stats.
+	StatsHandler stats.Handler
 }
 
 // TargetInfo contains the information of the target such as network address and metadata.
@@ -457,6 +511,9 @@ type ClientTransport interface {
 	// receives the draining signal from the server (e.g., GOAWAY frame in
 	// HTTP/2).
 	GoAway() <-chan struct{}
+
+	// GetGoAwayReason returns the reason why GoAway frame was received.
+	GetGoAwayReason() GoAwayReason
 }
 
 // ServerTransport is the common interface for all gRPC server-side transport
@@ -466,7 +523,7 @@ type ClientTransport interface {
 // Write methods for a given Stream will be called serially.
 type ServerTransport interface {
 	// HandleStreams receives incoming streams using the given handler.
-	HandleStreams(func(*Stream))
+	HandleStreams(func(*Stream), func(context.Context, string) context.Context)
 
 	// WriteHeader sends the header metadata for the given stream.
 	// WriteHeader may not be called on all streams.
@@ -476,10 +533,9 @@ type ServerTransport interface {
 	// Write may not be called on all streams.
 	Write(s *Stream, data []byte, opts *Options) error
 
-	// WriteStatus sends the status of a stream to the client.
+	// WriteStatus sends the status of a stream to the client.  WriteStatus is
-	// WriteStatus is the final call made on a stream and always
+	// the final call made on a stream and always occurs.
-	// occurs.
+	WriteStatus(s *Stream, st *status.Status) error
-	WriteStatus(s *Stream, statusCode codes.Code, statusDesc string) error
 
 	// Close tears down the transport. Once it is called, the transport
 	// should not be accessed any more. All the pending streams and their
@@ -545,6 +601,8 @@ var (
 	ErrStreamDrain = streamErrorf(codes.Unavailable, "the server stops accepting new RPCs")
 )
 
+// TODO: See if we can replace StreamError with status package errors.
+
 // StreamError is an error that only affects one stream within a connection.
 type StreamError struct {
 	Code codes.Code
@@ -552,7 +610,7 @@ type StreamError struct {
 }
 
 func (e StreamError) Error() string {
-	return fmt.Sprintf("stream error: code = %d desc = %q", e.Code, e.Desc)
+	return fmt.Sprintf("stream error: code = %s desc = %q", e.Code, e.Desc)
 }
 
 // ContextErr converts the error from context package into a StreamError.
@@ -593,3 +651,16 @@ func wait(ctx context.Context, done, goAway, closing <-chan struct{}, proceed <-
 		return i, nil
 	}
 }
+
+// GoAwayReason contains the reason for the GoAway frame received.
+type GoAwayReason uint8
+
+const (
+	// Invalid indicates that no GoAway frame is received.
+	Invalid GoAwayReason = 0
+	// NoReason is the default value when GoAway frame is received.
+	NoReason GoAwayReason = 1
+	// TooManyPings indicates that a GoAway frame with ErrCodeEnhanceYourCalm
+	// was recieved and that the debug data said "too_many_pings".
+	TooManyPings GoAwayReason = 2
+)