DockerCLI/vendor/go.opentelemetry.io/otel/trace/doc.go

67 lines
1.9 KiB
Go

// Copyright The OpenTelemetry 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 trace provides an implementation of the tracing part of the
OpenTelemetry API.
To participate in distributed traces a Span needs to be created for the
operation being performed as part of a traced workflow. It its simplest form:
var tracer trace.Tracer
func init() {
tracer = otel.Tracer("instrumentation/package/name")
}
func operation(ctx context.Context) {
var span trace.Span
ctx, span = tracer.Start(ctx, "operation")
defer span.End()
// ...
}
A Tracer is unique to the instrumentation and is used to create Spans.
Instrumentation should be designed to accept a TracerProvider from which it
can create its own unique Tracer. Alternatively, the registered global
TracerProvider from the go.opentelemetry.io/otel package can be used as
a default.
const (
name = "instrumentation/package/name"
version = "0.1.0"
)
type Instrumentation struct {
tracer trace.Tracer
}
func NewInstrumentation(tp trace.TracerProvider) *Instrumentation {
if tp == nil {
tp = otel.TracerProvider()
}
return &Instrumentation{
tracer: tp.Tracer(name, trace.WithInstrumentationVersion(version)),
}
}
func operation(ctx context.Context, inst *Instrumentation) {
var span trace.Span
ctx, span = inst.tracer.Start(ctx, "operation")
defer span.End()
// ...
}
*/
package trace // import "go.opentelemetry.io/otel/trace"