[query][test] Add unit test for tracing http requests in query server (…

…#6131)

## Which problem is this PR solving?
- Towards #6026 

## Description of the changes
- Added a unit test for tracing http request endpoints in query server 

## How was this change tested?
- CI

## Checklist
- [x] I have read
https://github.com/jaegertracing/jaeger/blob/master/CONTRIBUTING_GUIDELINES.md
- [x] I have signed all commits
- [x] I have added unit tests for the new functionality
- [x] I have run lint and test steps successfully
  - for `jaeger`: `make lint test`
  - for `jaeger-ui`: `yarn lint` and `yarn test`

---------

Signed-off-by: Mahad Zaryab <[email protected]>

cmd/query/app/server_test.go

@@ -4,6 +4,7 @@
 package app
 
 import (
+	"bytes"
 	"context"
 	"crypto/tls"
 	"fmt"
@@ -12,6 +13,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/gogo/protobuf/jsonpb"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/mock"
 	"github.com/stretchr/testify/require"
@@ -20,6 +22,8 @@ import (
 	"go.opentelemetry.io/collector/config/confighttp"
 	"go.opentelemetry.io/collector/config/confignet"
 	"go.opentelemetry.io/collector/config/configtls"
+	sdktrace "go.opentelemetry.io/otel/sdk/trace"
+	"go.opentelemetry.io/otel/sdk/trace/tracetest"
 	"go.uber.org/zap"
 	"go.uber.org/zap/zaptest"
 	"go.uber.org/zap/zaptest/observer"
@@ -855,3 +859,106 @@ func TestServerHTTPTenancy(t *testing.T) {
 		})
 	}
 }
+
+func TestServerHTTP_TracesRequest(t *testing.T) {
+	makeMockTrace := func(t *testing.T) *model.Trace {
+		out := new(bytes.Buffer)
+		err := new(jsonpb.Marshaler).Marshal(out, mockTrace)
+		require.NoError(t, err)
+		var trace model.Trace
+		require.NoError(t, jsonpb.Unmarshal(out, &trace))
+		trace.Spans[1].References = []model.SpanRef{
+			{TraceID: model.NewTraceID(0, 0)},
+		}
+		return &trace
+	}
+
+	tests := []struct {
+		name          string
+		httpEndpoint  string
+		grpcEndpoint  string
+		queryString   string
+		expectedTrace string
+	}{
+		{
+			name:          "different ports",
+			httpEndpoint:  ":8080",
+			grpcEndpoint:  ":8081",
+			queryString:   "/api/traces/123456aBC",
+			expectedTrace: "/api/traces/{traceID}",
+		},
+		{
+			name:          "different ports for v3 api",
+			httpEndpoint:  ":8080",
+			grpcEndpoint:  ":8081",
+			queryString:   "/api/v3/traces/123456aBC",
+			expectedTrace: "/api/v3/traces/{trace_id}",
+		},
+		{
+			name:          "same port",
+			httpEndpoint:  ":8080",
+			grpcEndpoint:  ":8080",
+			queryString:   "/api/traces/123456aBC",
+			expectedTrace: "/api/traces/{traceID}",
+		},
+		{
+			name:          "same port for v3 api",
+			httpEndpoint:  ":8080",
+			grpcEndpoint:  ":8080",
+			queryString:   "/api/v3/traces/123456aBC",
+			expectedTrace: "/api/v3/traces/{trace_id}",
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			serverOptions := &QueryOptions{
+				HTTP: confighttp.ServerConfig{
+					Endpoint: test.httpEndpoint,
+				},
+				GRPC: configgrpc.ServerConfig{
+					NetAddr: confignet.AddrConfig{
+						Endpoint:  test.grpcEndpoint,
+						Transport: confignet.TransportTypeTCP,
+					},
+				},
+			}
+
+			exporter := tracetest.NewInMemoryExporter()
+			tracerProvider := sdktrace.NewTracerProvider(
+				sdktrace.WithSyncer(exporter),
+				sdktrace.WithSampler(sdktrace.AlwaysSample()),
+			)
+			tracer := jtracer.JTracer{OTEL: tracerProvider}
+
+			tenancyMgr := tenancy.NewManager(&serverOptions.Tenancy)
+			querySvc := makeQuerySvc()
+			querySvc.spanReader.On("GetTrace", mock.AnythingOfType("*context.valueCtx"), model.NewTraceID(0, 0x123456abc)).
+				Return(makeMockTrace(t), nil).Once()
+			telset := initTelSet(zaptest.NewLogger(t), &tracer, healthcheck.New())
+
+			server, err := NewServer(context.Background(), querySvc.qs,
+				nil, serverOptions, tenancyMgr, telset)
+			require.NoError(t, err)
+			require.NoError(t, server.Start(context.Background()))
+			t.Cleanup(func() {
+				require.NoError(t, server.Close())
+			})
+
+			req, err := http.NewRequest(http.MethodGet, "http://localhost:8080"+test.queryString, nil)
+			require.NoError(t, err)
+
+			client := &http.Client{}
+			resp, err := client.Do(req)
+			require.NoError(t, err)
+
+			if test.expectedTrace != "" {
+				assert.Len(t, exporter.GetSpans(), 1, "HTTP request was traced and span reported")
+				assert.Equal(t, test.expectedTrace, exporter.GetSpans()[0].Name)
+			} else {
+				assert.Empty(t, exporter.GetSpans(), "HTTP request was not traced")
+			}
+			require.NoError(t, resp.Body.Close())
+		})
+	}
+}