Add tests to Retention service

internal/meta_client.go

@@ -32,6 +32,8 @@ type MetaClientMock struct {
 
 	OpenFn func() error
 
+	PruneShardGroupsFn func() error
+
 	RetentionPolicyFn func(database, name string) (rpi *meta.RetentionPolicyInfo, err error)
 
 	AuthenticateFn           func(username, password string) (ui meta.User, err error)
@@ -164,3 +166,5 @@ func (c *MetaClientMock) Users() []meta.UserInfo                  { return c.Use
 func (c *MetaClientMock) Open() error                { return c.OpenFn() }
 func (c *MetaClientMock) Data() meta.Data            { return c.DataFn() }
 func (c *MetaClientMock) SetData(d *meta.Data) error { return c.SetDataFn(d) }
+
+func (c *MetaClientMock) PruneShardGroups() error { return c.PruneShardGroupsFn() }

services/retention/service.go

@@ -22,7 +22,7 @@ type Service struct {
 		DeleteShard(shardID uint64) error
 	}
 
-	checkInterval time.Duration
+	config Config
 	wg     sync.WaitGroup
 	done   chan struct{}
 
@@ -32,15 +32,21 @@ type Service struct {
 // NewService returns a configured retention policy enforcement service.
 func NewService(c Config) *Service {
 	return &Service{
-		checkInterval: time.Duration(c.CheckInterval),
-		done:          make(chan struct{}),
+		config: c,
 		logger: zap.New(zap.NullEncoder()),
 	}
 }
 
 // Open starts retention policy enforcement.
 func (s *Service) Open() error {
-	s.logger.Info(fmt.Sprint("Starting retention policy enforcement service with check interval of ", s.checkInterval))
+	if !s.config.Enabled || s.done != nil {
+		return nil
+	}
+
+	s.logger.Info(fmt.Sprint("Starting retention policy enforcement service with check interval of ", s.config.CheckInterval))
+
+	s.done = make(chan struct{})
+
 	s.wg.Add(2)
 	go s.deleteShardGroups()
 	go s.deleteShards()
@@ -49,9 +55,15 @@ func (s *Service) Open() error {
 
 // Close stops retention policy enforcement.
 func (s *Service) Close() error {
+	if !s.config.Enabled || s.done == nil {
+		return nil
+	}
+
 	s.logger.Info("retention policy enforcement terminating")
 	close(s.done)
+
 	s.wg.Wait()
+	s.done = nil
 	return nil
 }
 
@@ -63,7 +75,7 @@ func (s *Service) WithLogger(log zap.Logger) {
 func (s *Service) deleteShardGroups() {
 	defer s.wg.Done()
 
-	ticker := time.NewTicker(s.checkInterval)
+	ticker := time.NewTicker(time.Duration(s.config.CheckInterval))
 	defer ticker.Stop()
 	for {
 		select {
@@ -92,7 +104,7 @@ func (s *Service) deleteShardGroups() {
 func (s *Service) deleteShards() {
 	defer s.wg.Done()
 
-	ticker := time.NewTicker(s.checkInterval)
+	ticker := time.NewTicker(time.Duration(s.config.CheckInterval))
 	defer ticker.Stop()
 	for {
 		select {

services/retention/service_test.go

@@ -0,0 +1,78 @@
+package retention_test
+
+import (
+	"bytes"
+	"testing"
+
+	"github.com/influxdata/influxdb/internal"
+	"github.com/influxdata/influxdb/services/retention"
+	"github.com/uber-go/zap"
+)
+
+func TestService_OpenDisabled(t *testing.T) {
+	// Opening a disabled service should be a no-op.
+	c := retention.NewConfig()
+	c.Enabled = false
+	s := NewService(c)
+
+	if err := s.Open(); err != nil {
+		t.Fatal(err)
+	}
+
+	if s.LogBuf.String() != "" {
+		t.Fatalf("service logged %q, didn't expect any logging", s.LogBuf.String())
+	}
+}
+
+func TestService_OpenClose(t *testing.T) {
+	// Opening a disabled service should be a no-op.
+	s := NewService(retention.NewConfig())
+
+	if err := s.Open(); err != nil {
+		t.Fatal(err)
+	}
+
+	if s.LogBuf.String() == "" {
+		t.Fatal("service didn't log anything on open")
+	}
+
+	// Reopening is a no-op
+	if err := s.Open(); err != nil {
+		t.Fatal(err)
+	}
+
+	if err := s.Close(); err != nil {
+		t.Fatal(err)
+	}
+
+	// Re-closing is a no-op
+	if err := s.Close(); err != nil {
+		t.Fatal(err)
+	}
+}
+
+type Service struct {
+	MetaClient *internal.MetaClientMock
+	TSDBStore  *internal.TSDBStoreMock
+
+	LogBuf bytes.Buffer
+	*retention.Service
+}
+
+func NewService(c retention.Config) *Service {
+	s := &Service{
+		MetaClient: &internal.MetaClientMock{},
+		TSDBStore:  &internal.TSDBStoreMock{},
+		Service:    retention.NewService(c),
+	}
+
+	l := zap.New(
+		zap.NewTextEncoder(),
+		zap.Output(zap.AddSync(&s.LogBuf)),
+	)
+	s.WithLogger(l)
+
+	s.Service.MetaClient = s.MetaClient
+	s.Service.TSDBStore = s.TSDBStore
+	return s
+}