github.com/annwntech/go-micro/v2@v2.9.5/debug/trace/memory/memory.go (about)

     1  package memory
     2  
     3  import (
     4  	"context"
     5  	"time"
     6  
     7  	"github.com/google/uuid"
     8  	"github.com/annwntech/go-micro/v2/debug/trace"
     9  	"github.com/annwntech/go-micro/v2/util/ring"
    10  )
    11  
    12  type Tracer struct {
    13  	opts trace.Options
    14  
    15  	// ring buffer of traces
    16  	buffer *ring.Buffer
    17  }
    18  
    19  func (t *Tracer) Read(opts ...trace.ReadOption) ([]*trace.Span, error) {
    20  	var options trace.ReadOptions
    21  	for _, o := range opts {
    22  		o(&options)
    23  	}
    24  
    25  	sp := t.buffer.Get(t.buffer.Size())
    26  
    27  	spans := make([]*trace.Span, 0, len(sp))
    28  
    29  	for _, span := range sp {
    30  		val := span.Value.(*trace.Span)
    31  		// skip if trace id is specified and doesn't match
    32  		if len(options.Trace) > 0 && val.Trace != options.Trace {
    33  			continue
    34  		}
    35  		spans = append(spans, val)
    36  	}
    37  
    38  	return spans, nil
    39  }
    40  
    41  func (t *Tracer) Start(ctx context.Context, name string) (context.Context, *trace.Span) {
    42  	span := &trace.Span{
    43  		Name:     name,
    44  		Trace:    uuid.New().String(),
    45  		Id:       uuid.New().String(),
    46  		Started:  time.Now(),
    47  		Metadata: make(map[string]string),
    48  	}
    49  
    50  	// return span if no context
    51  	if ctx == nil {
    52  		return trace.ToContext(context.Background(), span.Trace, span.Id), span
    53  	}
    54  	traceID, parentSpanID, ok := trace.FromContext(ctx)
    55  	// If the trace can not be found in the header,
    56  	// that means this is where the trace is created.
    57  	if !ok {
    58  		return trace.ToContext(ctx, span.Trace, span.Id), span
    59  	}
    60  
    61  	// set trace id
    62  	span.Trace = traceID
    63  	// set parent
    64  	span.Parent = parentSpanID
    65  
    66  	// return the span
    67  	return trace.ToContext(ctx, span.Trace, span.Id), span
    68  }
    69  
    70  func (t *Tracer) Finish(s *trace.Span) error {
    71  	// set finished time
    72  	s.Duration = time.Since(s.Started)
    73  	// save the span
    74  	t.buffer.Put(s)
    75  
    76  	return nil
    77  }
    78  
    79  func NewTracer(opts ...trace.Option) trace.Tracer {
    80  	var options trace.Options
    81  	for _, o := range opts {
    82  		o(&options)
    83  	}
    84  
    85  	return &Tracer{
    86  		opts: options,
    87  		// the last 256 requests
    88  		buffer: ring.New(256),
    89  	}
    90  }