github.com/matrixorigin/matrixone@v1.2.0/pkg/util/trace/impl/motrace/batch_span_processor.go (about)

     1  // Copyright The OpenTelemetry Authors
     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  // Portions of this file are additionally subject to the following
    16  // copyright.
    17  //
    18  // Copyright (C) 2022 Matrix Origin.
    19  //
    20  // Modified the behavior and the interface of the step.
    21  
    22  package motrace
    23  
    24  import (
    25  	"context"
    26  	"github.com/matrixorigin/matrixone/pkg/util/trace"
    27  	"sync"
    28  
    29  	"github.com/matrixorigin/matrixone/pkg/util/batchpipe"
    30  )
    31  
    32  var _ trace.SpanProcessor = &batchSpanProcessor{}
    33  
    34  // batchSpanProcessor is a SpanProcessor that batches asynchronously-received
    35  // spans and sends them to a trace.Exporter when complete.
    36  type batchSpanProcessor struct {
    37  	e BatchProcessor
    38  
    39  	stopWait sync.WaitGroup
    40  	stopOnce sync.Once
    41  	stopCh   chan struct{}
    42  }
    43  
    44  func NewBatchSpanProcessor(exporter BatchProcessor) trace.SpanProcessor {
    45  	bsp := &batchSpanProcessor{
    46  		e:      exporter,
    47  		stopCh: make(chan struct{}),
    48  	}
    49  
    50  	return bsp
    51  }
    52  
    53  // OnStart method does nothing.
    54  func (bsp *batchSpanProcessor) OnStart(parent context.Context, s trace.Span) {}
    55  
    56  // OnEnd method enqueues a ReadOnlySpan for later processing.
    57  func (bsp *batchSpanProcessor) OnEnd(s trace.Span) {
    58  	// Do not enqueue spans if we are just going to drop them.
    59  	if bsp.e == nil {
    60  		return
    61  	}
    62  	if i, ok := s.(batchpipe.HasName); !ok {
    63  		panic("No implement batchpipe.HasName")
    64  	} else {
    65  		bsp.e.Collect(DefaultContext(), i)
    66  	}
    67  }
    68  
    69  // Shutdown flushes the queue and waits until all spans are processed.
    70  // It only executes once. Subsequent call does nothing.
    71  func (bsp *batchSpanProcessor) Shutdown(ctx context.Context) error {
    72  	var err error
    73  	bsp.stopOnce.Do(func() {
    74  		wait := make(chan struct{})
    75  		go func() {
    76  			close(bsp.stopCh)
    77  			bsp.stopWait.Wait()
    78  			if bsp.e != nil {
    79  				// bsp.e.Shutdown(ctx)
    80  				if err := bsp.e.Stop(true); err != nil {
    81  					// TODO: otel.Handle(err)
    82  					panic(err)
    83  				}
    84  			}
    85  			close(wait)
    86  		}()
    87  		// Wait until the wait group is done or the context is cancelled
    88  		select {
    89  		case <-wait:
    90  		case <-ctx.Done():
    91  			err = ctx.Err()
    92  		}
    93  	})
    94  	return err
    95  }