71 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			Go
		
	
	
	
			
		
		
	
	
			71 lines
		
	
	
		
			2.1 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.
 | 
						|
 | 
						|
This package is currently in a pre-GA phase. Backwards incompatible changes
 | 
						|
may be introduced in subsequent minor version releases as we work to track the
 | 
						|
evolving OpenTelemetry specification and user feedback.
 | 
						|
 | 
						|
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"
 |