Chore: Fix plugins manager process data race in tests (#81914)

* Chore: synchronize writes to pkg.plugins.log.Logs to prevent data races in test code

* Chore: fix data race in tests in plugins process manager

* Chore: improve Logs method naming

* Chore: fix type change

pkg/plugins/log/fake.go

@@ -1,6 +1,9 @@
 package log
 
-import "context"
+import (
+	"context"
+	"sync"
+)
 
 var _ Logger = (*TestLogger)(nil)
 
@@ -20,27 +23,19 @@ func (f *TestLogger) New(_ ...any) Logger {
 }
 
 func (f *TestLogger) Info(msg string, ctx ...any) {
-	f.InfoLogs.Calls++
+	f.InfoLogs.Call(msg, ctx)
-	f.InfoLogs.Message = msg
-	f.InfoLogs.Ctx = ctx
 }
 
 func (f *TestLogger) Warn(msg string, ctx ...any) {
-	f.WarnLogs.Calls++
+	f.WarnLogs.Call(msg, ctx)
-	f.WarnLogs.Message = msg
-	f.WarnLogs.Ctx = ctx
 }
 
 func (f *TestLogger) Debug(msg string, ctx ...any) {
-	f.DebugLogs.Calls++
+	f.DebugLogs.Call(msg, ctx)
-	f.DebugLogs.Message = msg
-	f.DebugLogs.Ctx = ctx
 }
 
 func (f *TestLogger) Error(msg string, ctx ...any) {
-	f.ErrorLogs.Calls++
+	f.ErrorLogs.Call(msg, ctx)
-	f.ErrorLogs.Message = msg
-	f.ErrorLogs.Ctx = ctx
 }
 
 func (f *TestLogger) FromContext(_ context.Context) Logger {
@@ -51,6 +46,16 @@ type Logs struct {
 	Calls   int
 	Message string
 	Ctx     []any
+
+	mu sync.Mutex
+}
+
+func (l *Logs) Call(msg string, ctx ...any) {
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	l.Calls++
+	l.Message = msg
+	l.Ctx = ctx
 }
 
 var _ PrettyLogger = (*TestPrettyLogger)(nil)

pkg/plugins/manager/process/process.go

@@ -7,22 +7,24 @@ import (
 	"github.com/grafana/grafana/pkg/plugins"
 )
 
-var (
+const defaultKeepPluginAliveTickerDuration = time.Second
-	keepPluginAliveTickerDuration = time.Second * 1
-)
 
-type Service struct{}
+type Service struct {
+	keepPluginAliveTickerDuration time.Duration
+}
 
 func ProvideService() *Service {
-	return &Service{}
+	return &Service{
+		keepPluginAliveTickerDuration: defaultKeepPluginAliveTickerDuration,
+	}
 }
 
-func (*Service) Start(ctx context.Context, p *plugins.Plugin) error {
+func (s *Service) Start(ctx context.Context, p *plugins.Plugin) error {
 	if !p.IsManaged() || !p.Backend || p.SignatureError != nil {
 		return nil
 	}
 
-	if err := startPluginAndKeepItAlive(ctx, p); err != nil {
+	if err := s.startPluginAndKeepItAlive(ctx, p); err != nil {
 		return err
 	}
 
@@ -43,7 +45,7 @@ func (*Service) Stop(ctx context.Context, p *plugins.Plugin) error {
 	return nil
 }
 
-func startPluginAndKeepItAlive(ctx context.Context, p *plugins.Plugin) error {
+func (s *Service) startPluginAndKeepItAlive(ctx context.Context, p *plugins.Plugin) error {
 	if err := p.Start(ctx); err != nil {
 		return err
 	}
@@ -53,7 +55,7 @@ func startPluginAndKeepItAlive(ctx context.Context, p *plugins.Plugin) error {
 	}
 
 	go func(p *plugins.Plugin) {
-		if err := keepPluginAlive(p); err != nil {
+		if err := s.keepPluginAlive(p); err != nil {
 			p.Logger().Error("Attempt to restart killed plugin process failed", "error", err)
 		}
 	}(p)
@@ -62,8 +64,8 @@ func startPluginAndKeepItAlive(ctx context.Context, p *plugins.Plugin) error {
 }
 
 // keepPluginAlive will restart the plugin if the process is killed or exits
-func keepPluginAlive(p *plugins.Plugin) error {
+func (s *Service) keepPluginAlive(p *plugins.Plugin) error {
-	ticker := time.NewTicker(keepPluginAliveTickerDuration)
+	ticker := time.NewTicker(s.keepPluginAliveTickerDuration)
 
 	for {
 		<-ticker.C

pkg/plugins/manager/process/process_test.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"sync"
 	"testing"
-	"time"
 
 	"github.com/stretchr/testify/require"
 
@@ -15,7 +14,11 @@ import (
 )
 
 func TestProcessManager_Start(t *testing.T) {
+	t.Parallel()
+
 	t.Run("Plugin state determines process start", func(t *testing.T) {
+		t.Parallel()
+
 		tcs := []struct {
 			name               string
 			managed            bool
@@ -52,14 +55,20 @@ func TestProcessManager_Start(t *testing.T) {
 			},
 		}
 		for _, tc := range tcs {
+			// create a local copy of "tc" to allow concurrent access within tests to the different items of testCases,
+			// otherwise it would be like a moving pointer while tests run in parallel
+			tc := tc
+
 			t.Run(tc.name, func(t *testing.T) {
+				t.Parallel()
+
 				bp := fakes.NewFakeBackendPlugin(tc.managed)
 				p := createPlugin(t, bp, func(plugin *plugins.Plugin) {
 					plugin.Backend = tc.backend
 					plugin.SignatureError = tc.signatureError
 				})
 
-				m := &Service{}
+				m := ProvideService()
 				err := m.Start(context.Background(), p)
 				require.NoError(t, err)
 				require.Equal(t, tc.expectedStartCount, bp.StartCount)
@@ -74,18 +83,15 @@ func TestProcessManager_Start(t *testing.T) {
 	})
 
 	t.Run("Won't stop the plugin if the context is cancelled", func(t *testing.T) {
+		t.Parallel()
+
 		bp := fakes.NewFakeBackendPlugin(true)
 		p := createPlugin(t, bp, func(plugin *plugins.Plugin) {
 			plugin.Backend = true
 		})
 
-		tickerDuration := keepPluginAliveTickerDuration
+		m := ProvideService()
-		keepPluginAliveTickerDuration = 1 * time.Millisecond
+		m.keepPluginAliveTickerDuration = 1
-		defer func() {
-			keepPluginAliveTickerDuration = tickerDuration
-		}()
-
-		m := &Service{}
 		ctx := context.Background()
 		ctx, cancel := context.WithCancel(ctx)
 		err := m.Start(ctx, p)
@@ -100,7 +106,11 @@ func TestProcessManager_Start(t *testing.T) {
 }
 
 func TestProcessManager_Stop(t *testing.T) {
+	t.Parallel()
+
 	t.Run("Can stop a running plugin", func(t *testing.T) {
+		t.Parallel()
+
 		pluginID := "test-datasource"
 
 		bp := fakes.NewFakeBackendPlugin(true)
@@ -109,7 +119,7 @@ func TestProcessManager_Stop(t *testing.T) {
 			plugin.Backend = true
 		})
 
-		m := &Service{}
+		m := ProvideService()
 		err := m.Stop(context.Background(), p)
 		require.NoError(t, err)
 
@@ -120,18 +130,21 @@ func TestProcessManager_Stop(t *testing.T) {
 }
 
 func TestProcessManager_ManagedBackendPluginLifecycle(t *testing.T) {
-	bp := fakes.NewFakeBackendPlugin(true)
+	t.Parallel()
-	p := createPlugin(t, bp, func(plugin *plugins.Plugin) {
-		plugin.Backend = true
-	})
 
-	m := &Service{}
+	t.Run("When plugin process is killed, the process is restarted", func(t *testing.T) {
+		t.Parallel()
+		bp := fakes.NewFakeBackendPlugin(true)
+		p := createPlugin(t, bp, func(plugin *plugins.Plugin) {
+			plugin.Backend = true
+		})
 
-	err := m.Start(context.Background(), p)
+		m := ProvideService()
-	require.NoError(t, err)
+
-	require.Equal(t, 1, bp.StartCount)
+		err := m.Start(context.Background(), p)
+		require.NoError(t, err)
+		require.Equal(t, 1, bp.StartCount)
 
-	t.Run("When plugin process is killed, the process is restarted", func(t *testing.T) {
 		var wgKill sync.WaitGroup
 		wgKill.Add(1)
 		go func() {