DockerCLI/vendor/google.golang.org/grpc/internal/envconfig/envconfig.go

73 lines
2.6 KiB
Go

/*
*
* Copyright 2018 gRPC authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
// Package envconfig contains grpc settings configured by environment variables.
package envconfig
import (
"os"
"strconv"
"strings"
)
var (
// TXTErrIgnore is set if TXT errors should be ignored ("GRPC_GO_IGNORE_TXT_ERRORS" is not "false").
TXTErrIgnore = boolFromEnv("GRPC_GO_IGNORE_TXT_ERRORS", true)
// AdvertiseCompressors is set if registered compressor should be advertised
// ("GRPC_GO_ADVERTISE_COMPRESSORS" is not "false").
AdvertiseCompressors = boolFromEnv("GRPC_GO_ADVERTISE_COMPRESSORS", true)
// RingHashCap indicates the maximum ring size which defaults to 4096
// entries but may be overridden by setting the environment variable
// "GRPC_RING_HASH_CAP". This does not override the default bounds
// checking which NACKs configs specifying ring sizes > 8*1024*1024 (~8M).
RingHashCap = uint64FromEnv("GRPC_RING_HASH_CAP", 4096, 1, 8*1024*1024)
// PickFirstLBConfig is set if we should support configuration of the
// pick_first LB policy.
PickFirstLBConfig = boolFromEnv("GRPC_EXPERIMENTAL_PICKFIRST_LB_CONFIG", true)
// LeastRequestLB is set if we should support the least_request_experimental
// LB policy, which can be enabled by setting the environment variable
// "GRPC_EXPERIMENTAL_ENABLE_LEAST_REQUEST" to "true".
LeastRequestLB = boolFromEnv("GRPC_EXPERIMENTAL_ENABLE_LEAST_REQUEST", false)
// ALTSMaxConcurrentHandshakes is the maximum number of concurrent ALTS
// handshakes that can be performed.
ALTSMaxConcurrentHandshakes = uint64FromEnv("GRPC_ALTS_MAX_CONCURRENT_HANDSHAKES", 100, 1, 100)
)
func boolFromEnv(envVar string, def bool) bool {
if def {
// The default is true; return true unless the variable is "false".
return !strings.EqualFold(os.Getenv(envVar), "false")
}
// The default is false; return false unless the variable is "true".
return strings.EqualFold(os.Getenv(envVar), "true")
}
func uint64FromEnv(envVar string, def, min, max uint64) uint64 {
v, err := strconv.ParseUint(os.Getenv(envVar), 10, 64)
if err != nil {
return def
}
if v < min {
return min
}
if v > max {
return max
}
return v
}