open-consul/agent/rpc/subscribe/logger.go
2020-10-30 14:34:04 -04:00

70 lines
1.8 KiB
Go

package subscribe
import (
"sync"
"time"
"github.com/hashicorp/go-uuid"
"github.com/hashicorp/consul/agent/consul/stream"
"github.com/hashicorp/consul/proto/pbsubscribe"
)
// streamID is used in logs as a unique identifier for a subscription. The value
// is created lazily on the first call to String() so that we do not call it
// if trace logging is disabled.
// If a random UUID can not be created, defaults to the current time formatted
// as RFC3339Nano.
//
// TODO(banks) it might be nice one day to replace this with OpenTracing ID
// if one is set etc. but probably pointless until we support that properly
// in other places so it's actually propagated properly. For now this just
// makes lifetime of a stream more traceable in our regular server logs for
// debugging/dev.
type streamID struct {
once sync.Once
id string
}
func (s *streamID) String() string {
s.once.Do(func() {
var err error
s.id, err = uuid.GenerateUUID()
if err != nil {
s.id = time.Now().Format(time.RFC3339Nano)
}
})
return s.id
}
func newLoggerForRequest(l Logger, req *pbsubscribe.SubscribeRequest) Logger {
return l.With(
"topic", req.Topic.String(),
"dc", req.Datacenter,
"key", req.Key,
"namespace", req.Namespace,
"index", req.Index,
"stream_id", &streamID{})
}
type eventLogger struct {
logger Logger
snapshotDone bool
count uint64
}
func (l *eventLogger) Trace(e stream.Event) {
switch {
case e.IsEndOfSnapshot():
l.snapshotDone = true
l.logger.Trace("snapshot complete", "index", e.Index, "sent", l.count)
case e.IsNewSnapshotToFollow():
l.logger.Trace("starting new snapshot", "sent", l.count)
return
case l.snapshotDone:
l.logger.Trace("sending events", "index", e.Index, "sent", l.count, "batch_size", e.Len())
}
l.count += uint64(e.Len())
}