| // Copyright 2017, OpenCensus Authors |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package ocgrpc |
| |
| import ( |
| "context" |
| "strings" |
| |
| "google.golang.org/grpc/codes" |
| "google.golang.org/grpc/metadata" |
| "google.golang.org/grpc/stats" |
| "google.golang.org/grpc/status" |
| |
| "go.opencensus.io/trace" |
| "go.opencensus.io/trace/propagation" |
| ) |
| |
| const traceContextKey = "grpc-trace-bin" |
| |
| // TagRPC creates a new trace span for the client side of the RPC. |
| // |
| // It returns ctx with the new trace span added and a serialization of the |
| // SpanContext added to the outgoing gRPC metadata. |
| func (c *ClientHandler) traceTagRPC(ctx context.Context, rti *stats.RPCTagInfo) context.Context { |
| name := strings.TrimPrefix(rti.FullMethodName, "/") |
| name = strings.Replace(name, "/", ".", -1) |
| ctx, span := trace.StartSpan(ctx, name, |
| trace.WithSampler(c.StartOptions.Sampler), |
| trace.WithSpanKind(trace.SpanKindClient)) // span is ended by traceHandleRPC |
| traceContextBinary := propagation.Binary(span.SpanContext()) |
| return metadata.AppendToOutgoingContext(ctx, traceContextKey, string(traceContextBinary)) |
| } |
| |
| // TagRPC creates a new trace span for the server side of the RPC. |
| // |
| // It checks the incoming gRPC metadata in ctx for a SpanContext, and if |
| // it finds one, uses that SpanContext as the parent context of the new span. |
| // |
| // It returns ctx, with the new trace span added. |
| func (s *ServerHandler) traceTagRPC(ctx context.Context, rti *stats.RPCTagInfo) context.Context { |
| md, _ := metadata.FromIncomingContext(ctx) |
| name := strings.TrimPrefix(rti.FullMethodName, "/") |
| name = strings.Replace(name, "/", ".", -1) |
| traceContext := md[traceContextKey] |
| var ( |
| parent trace.SpanContext |
| haveParent bool |
| ) |
| if len(traceContext) > 0 { |
| // Metadata with keys ending in -bin are actually binary. They are base64 |
| // encoded before being put on the wire, see: |
| // https://github.com/grpc/grpc-go/blob/08d6261/Documentation/grpc-metadata.md#storing-binary-data-in-metadata |
| traceContextBinary := []byte(traceContext[0]) |
| parent, haveParent = propagation.FromBinary(traceContextBinary) |
| if haveParent && !s.IsPublicEndpoint { |
| ctx, _ := trace.StartSpanWithRemoteParent(ctx, name, parent, |
| trace.WithSpanKind(trace.SpanKindServer), |
| trace.WithSampler(s.StartOptions.Sampler), |
| ) |
| return ctx |
| } |
| } |
| ctx, span := trace.StartSpan(ctx, name, |
| trace.WithSpanKind(trace.SpanKindServer), |
| trace.WithSampler(s.StartOptions.Sampler)) |
| if haveParent { |
| span.AddLink(trace.Link{TraceID: parent.TraceID, SpanID: parent.SpanID, Type: trace.LinkTypeChild}) |
| } |
| return ctx |
| } |
| |
| func traceHandleRPC(ctx context.Context, rs stats.RPCStats) { |
| span := trace.FromContext(ctx) |
| // TODO: compressed and uncompressed sizes are not populated in every message. |
| switch rs := rs.(type) { |
| case *stats.Begin: |
| span.AddAttributes( |
| trace.BoolAttribute("Client", rs.Client), |
| trace.BoolAttribute("FailFast", rs.FailFast)) |
| case *stats.InPayload: |
| span.AddMessageReceiveEvent(0 /* TODO: messageID */, int64(rs.Length), int64(rs.WireLength)) |
| case *stats.OutPayload: |
| span.AddMessageSendEvent(0, int64(rs.Length), int64(rs.WireLength)) |
| case *stats.End: |
| if rs.Error != nil { |
| s, ok := status.FromError(rs.Error) |
| if ok { |
| span.SetStatus(trace.Status{Code: int32(s.Code()), Message: s.Message()}) |
| } else { |
| span.SetStatus(trace.Status{Code: int32(codes.Internal), Message: rs.Error.Error()}) |
| } |
| } |
| span.End() |
| } |
| } |