Restore NewGRPCHandler method (#4083)

cmd/query/app/grpc_handler.go

@@ -57,6 +57,39 @@ type GRPCHandler struct {
 	nowFn               func() time.Time
 }
 
+// GRPCHandlerOptions contains optional members of GRPCHandler.
+type GRPCHandlerOptions struct {
+	Logger *zap.Logger
+	Tracer opentracing.Tracer
+	NowFn  func() time.Time
+}
+
+// NewGRPCHandler returns a GRPCHandler.
+func NewGRPCHandler(queryService *querysvc.QueryService,
+	metricsQueryService querysvc.MetricsQueryService,
+	options GRPCHandlerOptions,
+) *GRPCHandler {
+	if options.Logger == nil {
+		options.Logger = zap.NewNop()
+	}
+
+	if options.Tracer == nil {
+		options.Tracer = opentracing.NoopTracer{}
+	}
+
+	if options.NowFn == nil {
+		options.NowFn = time.Now
+	}
+
+	return &GRPCHandler{
+		queryService:        queryService,
+		metricsQueryService: metricsQueryService,
+		logger:              options.Logger,
+		tracer:              options.Tracer,
+		nowFn:               options.NowFn,
+	}
+}
+
 var _ api_v2.QueryServiceServer = (*GRPCHandler)(nil)
 
 // GetTrace is the gRPC handler to fetch traces based on trace-id.

cmd/query/app/grpc_handler_test.go

@@ -155,15 +155,13 @@ func newGRPCServer(t *testing.T, q *querysvc.QueryService, mq querysvc.MetricsQu
 		)
 	}
 	grpcServer := grpc.NewServer(grpcOpts...)
-	grpcHandler := &GRPCHandler{
-		queryService:        q,
-		metricsQueryService: mq,
-		logger:              logger,
-		tracer:              tracer,
-		nowFn: func() time.Time {
+	grpcHandler := NewGRPCHandler(q, mq, GRPCHandlerOptions{
+		Logger: logger,
+		Tracer: tracer,
+		NowFn: func() time.Time {
 			return now
 		},
-	}
+	})
 	api_v2.RegisterQueryServiceServer(grpcServer, grpcHandler)
 	metrics.RegisterMetricsQueryServiceServer(grpcServer, grpcHandler)
 
@@ -1168,3 +1166,19 @@ func TestTenancyContextFlowGRPC(t *testing.T) {
 		server.spanReader.AssertExpectations(t)
 	})
 }
+
+func TestNewGRPCHandlerWithEmptyOptions(t *testing.T) {
+	disabledReader, err := disabled.NewMetricsReader()
+	require.NoError(t, err)
+
+	q := querysvc.NewQueryService(
+		&spanstoremocks.Reader{},
+		&depsmocks.Reader{},
+		querysvc.QueryServiceOptions{})
+
+	handler := NewGRPCHandler(q, disabledReader, GRPCHandlerOptions{})
+
+	assert.NotNil(t, handler.logger)
+	assert.NotNil(t, handler.tracer)
+	assert.NotNil(t, handler.nowFn)
+}

cmd/query/app/server.go

@@ -130,13 +130,10 @@ func createGRPCServer(querySvc *querysvc.QueryService, metricsQuerySvc querysvc.
 	server := grpc.NewServer(grpcOpts...)
 	reflection.Register(server)
 
-	handler := &GRPCHandler{
-		queryService:        querySvc,
-		metricsQueryService: metricsQuerySvc,
-		logger:              logger,
-		tracer:              tracer,
-		nowFn:               time.Now,
-	}
+	handler := NewGRPCHandler(querySvc, metricsQuerySvc, GRPCHandlerOptions{
+		Logger: logger,
+		Tracer: tracer,
+	})
 	healthServer := health.NewServer()
 
 	api_v2.RegisterQueryServiceServer(server, handler)