[extension/jaegarremotesamplingextension/internal] add goleak tests for jaegerremotesampling extension (#31661)

Related to
#30438
Resolves #31157

Signed-off-by: Israel Blancas <[email protected]>

Author: iblancasa

.chloggen/goleak_jaegerremotesamplingextension.yaml

@@ -0,0 +1,27 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: bug_fix
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: jaegerremotesamplingextension
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: "Fix leaking goroutine on shutdown"
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [31157]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: []

extension/jaegerremotesampling/internal/grpc.go

@@ -90,7 +90,7 @@ func (s *SamplingGRPCServer) Shutdown(ctx context.Context) error {
 		return errGRPCServerNotRunning
 	}
 
-	ch := make(chan struct{})
+	ch := make(chan struct{}, 1)
 	go func() {
 		s.grpcServer.GracefulStop()
 		ch <- struct{}{}

extension/jaegerremotesampling/internal/grpc_test.go

@@ -54,7 +54,7 @@ func TestSamplingGRPCServer_Shutdown(t *testing.T) {
 		{
 			name: "graceful stop is successful with delay",
 			grpcServer: &grpcServerMock{
-				timeToGracefulStop: 5 * time.Second,
+				timeToGracefulStop: time.Millisecond,
 			},
 			timeout: time.Minute,
 		},
@@ -63,29 +63,45 @@ func TestSamplingGRPCServer_Shutdown(t *testing.T) {
 			grpcServer: &grpcServerMock{
 				timeToGracefulStop: time.Minute,
 			},
-			timeout: 5 * time.Second,
-		},
-		{
-			name:    "grpc server not started",
-			timeout: time.Minute,
-			expect:  errGRPCServerNotRunning,
+			timeout: time.Millisecond,
 		},
 	}
 
 	for _, tc := range tt {
 		t.Run(tc.name, func(t *testing.T) {
 			srv := &SamplingGRPCServer{grpcServer: tc.grpcServer}
 			ctx, cancel := context.WithTimeout(context.Background(), tc.timeout)
+			assert.NoError(t, tc.grpcServer.Serve(nil))
 			defer cancel()
 			assert.Equal(t, tc.expect, srv.Shutdown(ctx))
 		})
 	}
 }
 
+func TestSamplingGRPCServerNotStarted_Shutdown(t *testing.T) {
+	srv := &SamplingGRPCServer{}
+	assert.Equal(t, errGRPCServerNotRunning, srv.Shutdown(context.Background()))
+}
+
 type grpcServerMock struct {
 	timeToGracefulStop time.Duration
+	timer              *time.Timer
+	quit               chan bool
 }
 
-func (g *grpcServerMock) Serve(_ net.Listener) error { return nil }
-func (g *grpcServerMock) Stop()                      {}
-func (g *grpcServerMock) GracefulStop()              { time.Sleep(g.timeToGracefulStop) }
+func (g *grpcServerMock) Serve(_ net.Listener) error {
+	g.timer = time.NewTimer(g.timeToGracefulStop)
+	g.quit = make(chan bool)
+	return nil
+}
+func (g *grpcServerMock) Stop() {
+	g.quit <- true
+}
+func (g *grpcServerMock) GracefulStop() {
+	select {
+	case <-g.quit:
+		return
+	case <-g.timer.C:
+		return
+	}
+}

extension/jaegerremotesampling/internal/package_test.go

@@ -0,0 +1,14 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package internal
+
+import (
+	"testing"
+
+	"go.uber.org/goleak"
+)
+
+func TestMain(m *testing.M) {
+	goleak.VerifyTestMain(m)
+}