micro/debug/trace/memory/memory.go
Janos Dobronszki 92571db693
Tracing: traces now correctly form a tree (#1170)
* First cut of trace

* Dial it back yo

* Defensive programming
2020-02-06 17:22:16 +00:00

91 lines
1.8 KiB
Go

package memory
import (
"context"
"time"
"github.com/google/uuid"
"github.com/micro/go-micro/v2/debug/trace"
"github.com/micro/go-micro/v2/util/ring"
)
type Tracer struct {
opts trace.Options
// ring buffer of traces
buffer *ring.Buffer
}
func (t *Tracer) Read(opts ...trace.ReadOption) ([]*trace.Span, error) {
var options trace.ReadOptions
for _, o := range opts {
o(&options)
}
sp := t.buffer.Get(t.buffer.Size())
var spans []*trace.Span
for _, span := range sp {
val := span.Value.(*trace.Span)
// skip if trace id is specified and doesn't match
if len(options.Trace) > 0 && val.Trace != options.Trace {
continue
}
spans = append(spans, val)
}
return spans, nil
}
func (t *Tracer) Start(ctx context.Context, name string) (context.Context, *trace.Span) {
span := &trace.Span{
Name: name,
Trace: uuid.New().String(),
Id: uuid.New().String(),
Started: time.Now(),
Metadata: make(map[string]string),
}
// return span if no context
if ctx == nil {
return trace.ToContext(context.Background(), span.Trace, span.Id), span
}
traceID, parentSpanID, ok := trace.FromContext(ctx)
// If the trace can not be found in the header,
// that means this is where the trace is created.
if !ok {
return trace.ToContext(ctx, span.Trace, span.Id), span
}
// set trace id
span.Trace = traceID
// set parent
span.Parent = parentSpanID
// return the span
return trace.ToContext(ctx, span.Trace, span.Id), span
}
func (t *Tracer) Finish(s *trace.Span) error {
// set finished time
s.Duration = time.Since(s.Started)
// save the span
t.buffer.Put(s)
return nil
}
func NewTracer(opts ...trace.Option) trace.Tracer {
var options trace.Options
for _, o := range opts {
o(&options)
}
return &Tracer{
opts: options,
// the last 256 requests
buffer: ring.New(256),
}
}