prometheus/vendor/github.com/uber/jaeger-client-go/observer.go

89 lines
2.8 KiB
Go

// Copyright (c) 2017 Uber Technologies, Inc.
//
// 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 jaeger
import opentracing "github.com/opentracing/opentracing-go"
// Observer can be registered with the Tracer to receive notifications about
// new Spans.
//
// Deprecated: use jaeger.ContribObserver instead.
type Observer interface {
OnStartSpan(operationName string, options opentracing.StartSpanOptions) SpanObserver
}
// SpanObserver is created by the Observer and receives notifications about
// other Span events.
//
// Deprecated: use jaeger.ContribSpanObserver instead.
type SpanObserver interface {
OnSetOperationName(operationName string)
OnSetTag(key string, value interface{})
OnFinish(options opentracing.FinishOptions)
}
// compositeObserver is a dispatcher to other observers
type compositeObserver struct {
observers []ContribObserver
}
// compositeSpanObserver is a dispatcher to other span observers
type compositeSpanObserver struct {
observers []ContribSpanObserver
}
// noopSpanObserver is used when there are no observers registered
// on the Tracer or none of them returns span observers from OnStartSpan.
var noopSpanObserver = &compositeSpanObserver{}
func (o *compositeObserver) append(contribObserver ContribObserver) {
o.observers = append(o.observers, contribObserver)
}
func (o *compositeObserver) OnStartSpan(sp opentracing.Span, operationName string, options opentracing.StartSpanOptions) ContribSpanObserver {
var spanObservers []ContribSpanObserver
for _, obs := range o.observers {
spanObs, ok := obs.OnStartSpan(sp, operationName, options)
if ok {
if spanObservers == nil {
spanObservers = make([]ContribSpanObserver, 0, len(o.observers))
}
spanObservers = append(spanObservers, spanObs)
}
}
if len(spanObservers) == 0 {
return noopSpanObserver
}
return &compositeSpanObserver{observers: spanObservers}
}
func (o *compositeSpanObserver) OnSetOperationName(operationName string) {
for _, obs := range o.observers {
obs.OnSetOperationName(operationName)
}
}
func (o *compositeSpanObserver) OnSetTag(key string, value interface{}) {
for _, obs := range o.observers {
obs.OnSetTag(key, value)
}
}
func (o *compositeSpanObserver) OnFinish(options opentracing.FinishOptions) {
for _, obs := range o.observers {
obs.OnFinish(options)
}
}