Function HTTPGRPCTracingInterceptor

middleware/http_tracing.go:187–209

HTTPGRPCTracingInterceptor adds additional information about the encapsulated HTTP request to httpgrpc trace spans. The httpgrpc client wraps HTTP requests up into a generic httpgrpc.HTTP/Handle gRPC method. The httpgrpc server unwraps httpgrpc.HTTP/Handle gRPC requests into HTTP requests and forwa

(router *mux.Router)

// span tags to whatever parent span is active in the caller, rather than the /httpgrpc.HTTP/Handle
// span created by the tracing middleware for requests that arrive over the network.
func HTTPGRPCTracingInterceptor(router *mux.Router) grpc.UnaryServerInterceptor {
	return func(ctx context.Context, req any, info *grpc.UnaryServerInfo, handler grpc.UnaryHandler) (resp any, err error) {
		if info.FullMethod != "/httpgrpc.HTTP/Handle" {
			return handler(ctx, req)
		}

		httpgrpcRequest, ok := req.(*httpgrpc.HTTPRequest)
		if !ok {
			return handler(ctx, req)
		}

		httpRequest, err := httpgrpc.ToHTTPRequest(ctx, httpgrpcRequest)
		if err != nil {
			return handler(ctx, req)
		}

		if opentracing.IsGlobalTracerRegistered() {
			return handleHTTPGRPCRequestWithOpenTracing(ctx, req, httpRequest, router, handler)
		}

		return handleHTTPGRPCRequestWithOTel(ctx, req, httpRequest, router, handler)
	}
}

func handleHTTPGRPCRequestWithOpenTracing(ctx context.Context, req any, httpRequest *http.Request, router *mux.Router, handler grpc.UnaryHandler) (any, error) {
	tracer := opentracing.GlobalTracer()