Create a /deep-dependencies endpoint

cmd/query/app/analytics/http_gateway.go

@@ -0,0 +1,90 @@
+// Copyright (c) 2025 The Jaeger Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package analytics
+
+import (
+	"encoding/json"
+	"net/http"
+
+	"github.com/gorilla/mux"
+	"go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
+	"go.opentelemetry.io/otel/trace"
+)
+
+const (
+	routeGetDeepDependencies = "/api/deep-dependencies"
+)
+
+// HTTPGateway exposes analytics HTTP endpoints.
+type HTTPGateway struct{}
+
+func RegisterRoutes(router *mux.Router) {
+	addRoute(router, getDeepDependencies, routeGetDeepDependencies).Methods(http.MethodGet)
+}
+
+// addRoute adds a new endpoint to the router with given path and handler function.
+// This code is mostly copied from ../http_handler.
+func addRoute(
+	router *mux.Router,
+	f func(http.ResponseWriter, *http.Request),
+	route string,
+	_ ...any, /* args */
+) *mux.Route {
+	var handler http.Handler = http.HandlerFunc(f)
+	handler = otelhttp.WithRouteTag(route, handler)
+	handler = spanNameHandler(route, handler)
+	return router.HandleFunc(route, handler.ServeHTTP)
+}
+
+func spanNameHandler(spanName string, handler http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		span := trace.SpanFromContext(r.Context())
+		span.SetName(spanName)
+		handler.ServeHTTP(w, r)
+	})
+}
+
+func getDeepDependencies(w http.ResponseWriter, _ *http.Request) {
+	dependencies := TDdgPayload{
+		Dependencies: []TDdgPayloadPath{
+			{
+				Path: []TDdgPayloadEntry{
+					{Service: "sample-serviceA", Operation: "sample-opA"},
+					{Service: "sample-serviceB", Operation: "sample-opB"},
+				},
+				Attributes: []Attribute{
+					{Key: "exemplar_trace_id", Value: "abc123"},
+				},
+			},
+		},
+	}
+
+	res, err := json.Marshal(dependencies)
+	if err != nil {
+		http.Error(w, "Failed to encode response", http.StatusNotImplemented)
+		return
+	}
+	w.Header().Set("Content-Type", "application/json")
+	w.Write(res)
+}
+
+// Structs that need to be used or created for deep dependencies
+type TDdgPayloadEntry struct {
+	Operation string `json:"operation"`
+	Service   string `json:"service"`
+}
+
+type Attribute struct {
+	Key   string `json:"key"`
+	Value string `json:"value"`
+}
+
+type TDdgPayloadPath struct {
+	Path       []TDdgPayloadEntry `json:"path"`
+	Attributes []Attribute        `json:"attributes"`
+}
+
+type TDdgPayload struct {
+	Dependencies []TDdgPayloadPath `json:"dependencies"`
+}

cmd/query/app/analytics/http_gateway_test.go

@@ -0,0 +1,97 @@
+// Copyright (c) 2025 The Jaeger Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package analytics
+
+import (
+	"encoding/json"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/gorilla/mux"
+	"github.com/stretchr/testify/require"
+
+	_ "github.com/jaegertracing/jaeger/pkg/gogocodec" // force gogo codec registration
+)
+
+type testGateway struct {
+	url    string
+	router *mux.Router
+	// used to set a tenancy header when executing requests
+	setupRequest func(*http.Request)
+}
+
+func TestHTTPGateway(
+	t *testing.T,
+) {
+	gw := setupHTTPGateway(t, "/")
+	gw.setupRequest = func(_ *http.Request) {}
+	t.Run("getDeepDependencies", gw.runGatewayGetDeepDependencies)
+}
+
+func (gw *testGateway) runGatewayGetDeepDependencies(t *testing.T) {
+	expectedPath := []TDdgPayloadEntry{
+		{Service: "sample-serviceA", Operation: "sample-opA"},
+		{Service: "sample-serviceB", Operation: "sample-opB"},
+	}
+	expectedAttributes := []Attribute{
+		{Key: "exemplar_trace_id", Value: "abc123"},
+	}
+
+	body, statusCode := gw.execRequest(t, "/api/deep-dependencies")
+
+	require.Equal(t, http.StatusOK, statusCode)
+
+	var response TDdgPayload
+	err := json.Unmarshal(body, &response)
+	require.NoError(t, err)
+
+	require.Len(t, response.Dependencies, 1)
+	require.Equal(t, expectedPath, response.Dependencies[0].Path)
+	require.Equal(t, expectedAttributes, response.Dependencies[0].Attributes)
+}
+
+func (gw *testGateway) execRequest(t *testing.T, url string) ([]byte, int) {
+	req, err := http.NewRequest(http.MethodGet, gw.url+url, nil)
+	require.NoError(t, err)
+	req.Header.Set("Content-Type", "application/json")
+	gw.setupRequest(req)
+	response, err := http.DefaultClient.Do(req)
+	require.NoError(t, err)
+	body, err := io.ReadAll(response.Body)
+	require.NoError(t, err)
+	require.NoError(t, response.Body.Close())
+	return body, response.StatusCode
+}
+
+func setupHTTPGatewayNoServer(
+	_ *testing.T,
+	basePath string,
+) *testGateway {
+	gw := &testGateway{}
+
+	gw.router = &mux.Router{}
+	if basePath != "" && basePath != "/" {
+		gw.router = gw.router.PathPrefix(basePath).Subrouter()
+	}
+	RegisterRoutes(gw.router)
+	return gw
+}
+
+func setupHTTPGateway(
+	t *testing.T,
+	basePath string,
+) *testGateway {
+	gw := setupHTTPGatewayNoServer(t, basePath)
+
+	httpServer := httptest.NewServer(gw.router)
+	t.Cleanup(func() { httpServer.Close() })
+
+	gw.url = httpServer.URL
+	if basePath != "/" {
+		gw.url += basePath
+	}
+	return gw
+}

cmd/query/app/analytics/package_test.go

@@ -0,0 +1,14 @@
+// Copyright (c) 2023 The Jaeger Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package analytics
+
+import (
+	"testing"
+
+	"github.com/jaegertracing/jaeger/pkg/testutils"
+)
+
+func TestMain(m *testing.M) {
+	testutils.VerifyGoLeaks(m)
+}

cmd/query/app/server.go

@@ -26,6 +26,7 @@ import (
 	"google.golang.org/grpc/reflection"
 
 	"github.com/jaegertracing/jaeger-idl/proto-gen/api_v2"
+	"github.com/jaegertracing/jaeger/cmd/query/app/analytics"
 	"github.com/jaegertracing/jaeger/cmd/query/app/apiv3"
 	"github.com/jaegertracing/jaeger/cmd/query/app/querysvc"
 	v2querysvc "github.com/jaegertracing/jaeger/cmd/query/app/querysvc/v2/querysvc"
@@ -105,7 +106,6 @@ func registerGRPCHandlers(
 
 	api_v2.RegisterQueryServiceServer(server, handler)
 	api_v3.RegisterQueryServiceServer(server, &apiv3.Handler{QueryService: v2QuerySvc})
-
 	healthServer.SetServingStatus("jaeger.api_v2.QueryService", grpc_health_v1.HealthCheckResponse_SERVING)
 	healthServer.SetServingStatus("jaeger.api_v2.metrics.MetricsQueryService", grpc_health_v1.HealthCheckResponse_SERVING)
 	healthServer.SetServingStatus("jaeger.api_v3.QueryService", grpc_health_v1.HealthCheckResponse_SERVING)
@@ -183,6 +183,8 @@ func initRouter(
 		Tracer:       telset.TracerProvider,
 	}).RegisterRoutes(r)
 
+	analytics.RegisterRoutes(r)
+
 	apiHandler.RegisterRoutes(r)
 	staticHandlerCloser := RegisterStaticHandler(r, telset.Logger, queryOpts, querySvc.GetCapabilities())