Пример #1
0
// New returns an RelayService backed by a gRPC client connection. It is the
// responsibility of the caller to dial, and later close, the connection.
func New(conn *grpc.ClientConn, tracer stdopentracing.Tracer, logger log.Logger) relay.Service {
	// We construct a single ratelimiter middleware, to limit the total outgoing
	// QPS from this client to all methods on the remote instance. We also
	// construct per-endpoint circuitbreaker middlewares to demonstrate how
	// that's done, although they could easily be combined into a single breaker
	// for the entire remote instance, too.

	limiter := ratelimit.NewTokenBucketLimiter(jujuratelimit.NewBucketWithRate(100, 100))

	var connectEndpoint endpoint.Endpoint
	{
		connectEndpoint = grpctransport.NewClient(
			conn,
			"Relay",
			"Connect",
			relay.EncodeGRPCConnectRequest,
			relay.DecodeGRPCConnectResponse,
			pb.ConnectReply{},
			grpctransport.ClientBefore(opentracing.ToGRPCRequest(tracer, logger)),
		).Endpoint()
		connectEndpoint = opentracing.TraceClient(tracer, "Connect")(connectEndpoint)
		connectEndpoint = limiter(connectEndpoint)
		connectEndpoint = circuitbreaker.Gobreaker(gobreaker.NewCircuitBreaker(gobreaker.Settings{
			Name:    "Connect",
			Timeout: 30 * time.Second,
		}))(connectEndpoint)
	}

	var joinEndpoint endpoint.Endpoint
	{
		joinEndpoint = grpctransport.NewClient(
			conn,
			"Relay",
			"Join",
			relay.EncodeGRPCJoinRequest,
			relay.DecodeGRPCJoinResponse,
			pb.JoinReply{},
			grpctransport.ClientBefore(opentracing.ToGRPCRequest(tracer, logger)),
		).Endpoint()
		joinEndpoint = opentracing.TraceClient(tracer, "Join")(joinEndpoint)
		joinEndpoint = limiter(joinEndpoint)
		joinEndpoint = circuitbreaker.Gobreaker(gobreaker.NewCircuitBreaker(gobreaker.Settings{
			Name:    "Join",
			Timeout: 30 * time.Second,
		}))(joinEndpoint)
	}

	return relay.Endpoints{
		ConnectEndpoint: connectEndpoint,
		JoinEndpoint:    joinEndpoint,
	}
}
Пример #2
0
func TestTraceGRPCRequestRoundtrip(t *testing.T) {
	logger := log.NewNopLogger()
	tracer := mocktracer.New()

	// Initialize the ctx with a Span to inject.
	beforeSpan := tracer.StartSpan("to_inject").(*mocktracer.MockSpan)
	defer beforeSpan.Finish()
	beforeSpan.Context().SetBaggageItem("baggage", "check")
	beforeCtx := opentracing.ContextWithSpan(context.Background(), beforeSpan)

	toGRPCFunc := kitot.ToGRPCRequest(tracer, logger)
	md := metadata.Pairs()
	// Call the RequestFunc.
	afterCtx := toGRPCFunc(beforeCtx, &md)

	// The Span should not have changed.
	afterSpan := opentracing.SpanFromContext(afterCtx)
	if beforeSpan != afterSpan {
		t.Errorf("Should not swap in a new span")
	}

	// No spans should have finished yet.
	finishedSpans := tracer.GetFinishedSpans()
	if want, have := 0, len(finishedSpans); want != have {
		t.Errorf("Want %v span(s), found %v", want, have)
	}

	// Use FromGRPCRequest to verify that we can join with the trace given MD.
	fromGRPCFunc := kitot.FromGRPCRequest(tracer, "joined", logger)
	joinCtx := fromGRPCFunc(afterCtx, &md)
	joinedSpan := opentracing.SpanFromContext(joinCtx).(*mocktracer.MockSpan)

	joinedContext := joinedSpan.Context().(*mocktracer.MockSpanContext)
	beforeContext := beforeSpan.Context().(*mocktracer.MockSpanContext)

	if joinedContext.SpanID == beforeContext.SpanID {
		t.Error("SpanID should have changed", joinedContext.SpanID, beforeContext.SpanID)
	}

	// Check that the parent/child relationship is as expected for the joined span.
	if want, have := beforeContext.SpanID, joinedSpan.ParentID; want != have {
		t.Errorf("Want ParentID %q, have %q", want, have)
	}
	if want, have := "joined", joinedSpan.OperationName; want != have {
		t.Errorf("Want %q, have %q", want, have)
	}
	if want, have := "check", joinedSpan.Context().BaggageItem("baggage"); want != have {
		t.Errorf("Want %q, have %q", want, have)
	}
}
Пример #3
0
// MakeConcatEndpointFactory returns a loadbalancer.Factory that transforms
// GRPC host:port strings into Endpoints that call the Concat method on a GRPC
// server at that address.
func MakeConcatEndpointFactory(tracer opentracing.Tracer, tracingLogger log.Logger) loadbalancer.Factory {
	return func(instance string) (endpoint.Endpoint, io.Closer, error) {
		cc, err := grpc.Dial(instance, grpc.WithInsecure())
		return grpctransport.NewClient(
			cc,
			"Add",
			"Concat",
			encodeConcatRequest,
			decodeConcatResponse,
			pb.ConcatReply{},
			grpctransport.SetClientBefore(kitot.ToGRPCRequest(tracer, tracingLogger)),
		).Endpoint(), cc, err
	}
}