Merge pull request #251 from yangzhouhan/master

add client streaming response trace and prefix all traces with "sent:" or "recv:"

call.go

@@ -133,7 +133,6 @@ func Invoke(ctx context.Context, method string, args, reply interface{}, cc *Cli
 			}
 		}()
 	}
-
 	callHdr := &transport.CallHdr{
 		Host:   cc.authority,
 		Method: method,
@@ -165,7 +164,7 @@ func Invoke(ctx context.Context, method string, args, reply interface{}, cc *Cli
 			return toRPCErr(err)
 		}
 		if EnableTracing {
-			c.traceInfo.tr.LazyLog(payload{args}, true)
+			c.traceInfo.tr.LazyLog(&payload{sent: true, msg: args}, true)
 		}
 		stream, err = sendRequest(ctx, cc.dopts.codec, callHdr, t, args, topts)
 		if err != nil {
@@ -184,7 +183,7 @@ func Invoke(ctx context.Context, method string, args, reply interface{}, cc *Cli
 			continue
 		}
 		if EnableTracing {
-			c.traceInfo.tr.LazyLog(payload{reply}, true)
+			c.traceInfo.tr.LazyLog(&payload{sent: false, msg: reply}, true)
 		}
 		t.CloseStream(stream, lastErr)
 		if lastErr != nil {

stream.go

@@ -166,7 +166,7 @@ func (cs *clientStream) SendMsg(m interface{}) (err error) {
 	if cs.tracing {
 		cs.mu.Lock()
 		if cs.traceInfo.tr != nil {
-			cs.traceInfo.tr.LazyLog(payload{m}, true)
+			cs.traceInfo.tr.LazyLog(&payload{sent: true, msg: m}, true)
 		}
 		cs.mu.Unlock()
 	}
@@ -195,6 +195,13 @@ func (cs *clientStream) RecvMsg(m interface{}) (err error) {
 		}
 	}()
 	if err == nil {
+		if cs.tracing {
+			cs.mu.Lock()
+			if cs.traceInfo.tr != nil {
+				cs.traceInfo.tr.LazyLog(&payload{sent: false, msg: m}, true)
+			}
+			cs.mu.Unlock()
+		}
 		if !cs.desc.ClientStreams || cs.desc.ServerStreams {
 			return
 		}

trace.go

@@ -93,12 +93,17 @@ func (f *firstLine) String() string {
 
 // payload represents an RPC request or response payload.
 type payload struct {
-	m interface{} // e.g. a proto.Message
+	sent bool        // whether this is an outgoing payload
+	msg  interface{} // e.g. a proto.Message
 	// TODO(dsymonds): add stringifying info to codec, and limit how much we hold here?
 }
 
 func (p payload) String() string {
-	return fmt.Sprint(p.m)
+	if p.sent {
+		return fmt.Sprintf("sent: %v", p.msg)
+	} else {
+		return fmt.Sprintf("recv: %v", p.msg)
+	}
 }
 
 type fmtStringer struct {