github.com/livekit/protocol@v1.16.1-0.20240517185851-47e4c6bba773/tracer/tracer.go (about)

     1  // Copyright 2023 LiveKit, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package tracer
    16  
    17  import "context"
    18  
    19  type Tracer interface {
    20  	Start(ctx context.Context, spanName string, opts ...interface{}) (context.Context, Span)
    21  }
    22  
    23  type Span interface {
    24  	RecordError(err error)
    25  	End()
    26  }
    27  
    28  var tracer Tracer = &NoOpTracer{}
    29  
    30  // Can be used for your own tracing (for example, with Lightstep)
    31  func SetTracer(t Tracer) {
    32  	tracer = t
    33  }
    34  
    35  func Start(ctx context.Context, spanName string, opts ...interface{}) (context.Context, Span) {
    36  	return tracer.Start(ctx, spanName, opts...)
    37  }
    38  
    39  type NoOpTracer struct{}
    40  
    41  func (t *NoOpTracer) Start(ctx context.Context, _ string, _ ...interface{}) (context.Context, Span) {
    42  	return ctx, &NoOpSpan{}
    43  }
    44  
    45  type NoOpSpan struct{}
    46  
    47  func (s *NoOpSpan) RecordError(_ error) {}
    48  
    49  func (s *NoOpSpan) End() {}