Modernize code generation (#3003)

Signed-off-by: Mikkel Oscar Lyderik Larsen <mikkel.larsen@zalando.de>

pkg/generated/informers/externalversions/acid.zalan.do/v1/postgresql.go

@@ -25,13 +25,13 @@ SOFTWARE.
 package v1
 
 import (
-	"context"
+	context "context"
 	time "time"
 
-	acidzalandov1 "github.com/zalando/postgres-operator/pkg/apis/acid.zalan.do/v1"
+	apisacidzalandov1 "github.com/zalando/postgres-operator/pkg/apis/acid.zalan.do/v1"
 	versioned "github.com/zalando/postgres-operator/pkg/generated/clientset/versioned"
 	internalinterfaces "github.com/zalando/postgres-operator/pkg/generated/informers/externalversions/internalinterfaces"
-	v1 "github.com/zalando/postgres-operator/pkg/generated/listers/acid.zalan.do/v1"
+	acidzalandov1 "github.com/zalando/postgres-operator/pkg/generated/listers/acid.zalan.do/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	runtime "k8s.io/apimachinery/pkg/runtime"
 	watch "k8s.io/apimachinery/pkg/watch"
@@ -42,7 +42,7 @@ import (
 // Postgresqls.
 type PostgresqlInformer interface {
 	Informer() cache.SharedIndexInformer
-	Lister() v1.PostgresqlLister
+	Lister() acidzalandov1.PostgresqlLister
 }
 
 type postgresqlInformer struct {
@@ -77,7 +77,7 @@ func NewFilteredPostgresqlInformer(client versioned.Interface, namespace string,
 				return client.AcidV1().Postgresqls(namespace).Watch(context.TODO(), options)
 			},
 		},
-		&acidzalandov1.Postgresql{},
+		&apisacidzalandov1.Postgresql{},
 		resyncPeriod,
 		indexers,
 	)
@@ -88,9 +88,9 @@ func (f *postgresqlInformer) defaultInformer(client versioned.Interface, resyncP
 }
 
 func (f *postgresqlInformer) Informer() cache.SharedIndexInformer {
-	return f.factory.InformerFor(&acidzalandov1.Postgresql{}, f.defaultInformer)
+	return f.factory.InformerFor(&apisacidzalandov1.Postgresql{}, f.defaultInformer)
 }
 
-func (f *postgresqlInformer) Lister() v1.PostgresqlLister {
-	return v1.NewPostgresqlLister(f.Informer().GetIndexer())
+func (f *postgresqlInformer) Lister() acidzalandov1.PostgresqlLister {
+	return acidzalandov1.NewPostgresqlLister(f.Informer().GetIndexer())
 }

pkg/generated/informers/externalversions/acid.zalan.do/v1/postgresteam.go

@@ -25,13 +25,13 @@ SOFTWARE.
 package v1
 
 import (
-	"context"
+	context "context"
 	time "time"
 
-	acidzalandov1 "github.com/zalando/postgres-operator/pkg/apis/acid.zalan.do/v1"
+	apisacidzalandov1 "github.com/zalando/postgres-operator/pkg/apis/acid.zalan.do/v1"
 	versioned "github.com/zalando/postgres-operator/pkg/generated/clientset/versioned"
 	internalinterfaces "github.com/zalando/postgres-operator/pkg/generated/informers/externalversions/internalinterfaces"
-	v1 "github.com/zalando/postgres-operator/pkg/generated/listers/acid.zalan.do/v1"
+	acidzalandov1 "github.com/zalando/postgres-operator/pkg/generated/listers/acid.zalan.do/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	runtime "k8s.io/apimachinery/pkg/runtime"
 	watch "k8s.io/apimachinery/pkg/watch"
@@ -42,7 +42,7 @@ import (
 // PostgresTeams.
 type PostgresTeamInformer interface {
 	Informer() cache.SharedIndexInformer
-	Lister() v1.PostgresTeamLister
+	Lister() acidzalandov1.PostgresTeamLister
 }
 
 type postgresTeamInformer struct {
@@ -77,7 +77,7 @@ func NewFilteredPostgresTeamInformer(client versioned.Interface, namespace strin
 				return client.AcidV1().PostgresTeams(namespace).Watch(context.TODO(), options)
 			},
 		},
-		&acidzalandov1.PostgresTeam{},
+		&apisacidzalandov1.PostgresTeam{},
 		resyncPeriod,
 		indexers,
 	)
@@ -88,9 +88,9 @@ func (f *postgresTeamInformer) defaultInformer(client versioned.Interface, resyn
 }
 
 func (f *postgresTeamInformer) Informer() cache.SharedIndexInformer {
-	return f.factory.InformerFor(&acidzalandov1.PostgresTeam{}, f.defaultInformer)
+	return f.factory.InformerFor(&apisacidzalandov1.PostgresTeam{}, f.defaultInformer)
 }
 
-func (f *postgresTeamInformer) Lister() v1.PostgresTeamLister {
-	return v1.NewPostgresTeamLister(f.Informer().GetIndexer())
+func (f *postgresTeamInformer) Lister() acidzalandov1.PostgresTeamLister {
+	return acidzalandov1.NewPostgresTeamLister(f.Informer().GetIndexer())
 }

pkg/generated/informers/externalversions/factory.go

@@ -49,11 +49,17 @@ type sharedInformerFactory struct {
 	lock             sync.Mutex
 	defaultResync    time.Duration
 	customResync     map[reflect.Type]time.Duration
+	transform        cache.TransformFunc
 
 	informers map[reflect.Type]cache.SharedIndexInformer
 	// startedInformers is used for tracking which informers have been started.
 	// This allows Start() to be called multiple times safely.
 	startedInformers map[reflect.Type]bool
+	// wg tracks how many goroutines were started.
+	wg sync.WaitGroup
+	// shuttingDown is true when Shutdown has been called. It may still be running
+	// because it needs to wait for goroutines.
+	shuttingDown bool
 }
 
 // WithCustomResyncConfig sets a custom resync period for the specified informer types.
@@ -82,6 +88,14 @@ func WithNamespace(namespace string) SharedInformerOption {
 	}
 }
 
+// WithTransform sets a transform on all informers.
+func WithTransform(transform cache.TransformFunc) SharedInformerOption {
+	return func(factory *sharedInformerFactory) *sharedInformerFactory {
+		factory.transform = transform
+		return factory
+	}
+}
+
 // NewSharedInformerFactory constructs a new instance of sharedInformerFactory for all namespaces.
 func NewSharedInformerFactory(client versioned.Interface, defaultResync time.Duration) SharedInformerFactory {
 	return NewSharedInformerFactoryWithOptions(client, defaultResync)
@@ -114,20 +128,39 @@ func NewSharedInformerFactoryWithOptions(client versioned.Interface, defaultResy
 	return factory
 }
 
-// Start initializes all requested informers.
 func (f *sharedInformerFactory) Start(stopCh <-chan struct{}) {
 	f.lock.Lock()
 	defer f.lock.Unlock()
 
+	if f.shuttingDown {
+		return
+	}
+
 	for informerType, informer := range f.informers {
 		if !f.startedInformers[informerType] {
-			go informer.Run(stopCh)
+			f.wg.Add(1)
+			// We need a new variable in each loop iteration,
+			// otherwise the goroutine would use the loop variable
+			// and that keeps changing.
+			informer := informer
+			go func() {
+				defer f.wg.Done()
+				informer.Run(stopCh)
+			}()
 			f.startedInformers[informerType] = true
 		}
 	}
 }
 
-// WaitForCacheSync waits for all started informers' cache were synced.
+func (f *sharedInformerFactory) Shutdown() {
+	f.lock.Lock()
+	f.shuttingDown = true
+	f.lock.Unlock()
+
+	// Will return immediately if there is nothing to wait for.
+	f.wg.Wait()
+}
+
 func (f *sharedInformerFactory) WaitForCacheSync(stopCh <-chan struct{}) map[reflect.Type]bool {
 	informers := func() map[reflect.Type]cache.SharedIndexInformer {
 		f.lock.Lock()
@@ -149,7 +182,7 @@ func (f *sharedInformerFactory) WaitForCacheSync(stopCh <-chan struct{}) map[ref
 	return res
 }
 
-// InternalInformerFor returns the SharedIndexInformer for obj using an internal
+// InformerFor returns the SharedIndexInformer for obj using an internal
 // client.
 func (f *sharedInformerFactory) InformerFor(obj runtime.Object, newFunc internalinterfaces.NewInformerFunc) cache.SharedIndexInformer {
 	f.lock.Lock()
@@ -167,6 +200,7 @@ func (f *sharedInformerFactory) InformerFor(obj runtime.Object, newFunc internal
 	}
 
 	informer = newFunc(f.client, resyncPeriod)
+	informer.SetTransform(f.transform)
 	f.informers[informerType] = informer
 
 	return informer
@@ -174,11 +208,59 @@ func (f *sharedInformerFactory) InformerFor(obj runtime.Object, newFunc internal
 
 // SharedInformerFactory provides shared informers for resources in all known
 // API group versions.
+//
+// It is typically used like this:
+//
+//	ctx, cancel := context.Background()
+//	defer cancel()
+//	factory := NewSharedInformerFactory(client, resyncPeriod)
+//	defer factory.WaitForStop()    // Returns immediately if nothing was started.
+//	genericInformer := factory.ForResource(resource)
+//	typedInformer := factory.SomeAPIGroup().V1().SomeType()
+//	factory.Start(ctx.Done())          // Start processing these informers.
+//	synced := factory.WaitForCacheSync(ctx.Done())
+//	for v, ok := range synced {
+//	    if !ok {
+//	        fmt.Fprintf(os.Stderr, "caches failed to sync: %v", v)
+//	        return
+//	    }
+//	}
+//
+//	// Creating informers can also be created after Start, but then
+//	// Start must be called again:
+//	anotherGenericInformer := factory.ForResource(resource)
+//	factory.Start(ctx.Done())
 type SharedInformerFactory interface {
 	internalinterfaces.SharedInformerFactory
-	ForResource(resource schema.GroupVersionResource) (GenericInformer, error)
+
+	// Start initializes all requested informers. They are handled in goroutines
+	// which run until the stop channel gets closed.
+	// Warning: Start does not block. When run in a go-routine, it will race with a later WaitForCacheSync.
+	Start(stopCh <-chan struct{})
+
+	// Shutdown marks a factory as shutting down. At that point no new
+	// informers can be started anymore and Start will return without
+	// doing anything.
+	//
+	// In addition, Shutdown blocks until all goroutines have terminated. For that
+	// to happen, the close channel(s) that they were started with must be closed,
+	// either before Shutdown gets called or while it is waiting.
+	//
+	// Shutdown may be called multiple times, even concurrently. All such calls will
+	// block until all goroutines have terminated.
+	Shutdown()
+
+	// WaitForCacheSync blocks until all started informers' caches were synced
+	// or the stop channel gets closed.
 	WaitForCacheSync(stopCh <-chan struct{}) map[reflect.Type]bool
 
+	// ForResource gives generic access to a shared informer of the matching type.
+	ForResource(resource schema.GroupVersionResource) (GenericInformer, error)
+
+	// InformerFor returns the SharedIndexInformer for obj using an internal
+	// client.
+	InformerFor(obj runtime.Object, newFunc internalinterfaces.NewInformerFunc) cache.SharedIndexInformer
+
 	Acid() acidzalando.Interface
 	Zalando() zalandoorg.Interface
 }

pkg/generated/informers/externalversions/generic.go

@@ -25,7 +25,7 @@ SOFTWARE.
 package externalversions
 
 import (
-	"fmt"
+	fmt "fmt"
 
 	v1 "github.com/zalando/postgres-operator/pkg/apis/acid.zalan.do/v1"
 	zalandoorgv1 "github.com/zalando/postgres-operator/pkg/apis/zalando.org/v1"

pkg/generated/informers/externalversions/zalando.org/v1/fabriceventstream.go

@@ -25,13 +25,13 @@ SOFTWARE.
 package v1
 
 import (
-	"context"
+	context "context"
 	time "time"
 
-	zalandoorgv1 "github.com/zalando/postgres-operator/pkg/apis/zalando.org/v1"
+	apiszalandoorgv1 "github.com/zalando/postgres-operator/pkg/apis/zalando.org/v1"
 	versioned "github.com/zalando/postgres-operator/pkg/generated/clientset/versioned"
 	internalinterfaces "github.com/zalando/postgres-operator/pkg/generated/informers/externalversions/internalinterfaces"
-	v1 "github.com/zalando/postgres-operator/pkg/generated/listers/zalando.org/v1"
+	zalandoorgv1 "github.com/zalando/postgres-operator/pkg/generated/listers/zalando.org/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	runtime "k8s.io/apimachinery/pkg/runtime"
 	watch "k8s.io/apimachinery/pkg/watch"
@@ -42,7 +42,7 @@ import (
 // FabricEventStreams.
 type FabricEventStreamInformer interface {
 	Informer() cache.SharedIndexInformer
-	Lister() v1.FabricEventStreamLister
+	Lister() zalandoorgv1.FabricEventStreamLister
 }
 
 type fabricEventStreamInformer struct {
@@ -77,7 +77,7 @@ func NewFilteredFabricEventStreamInformer(client versioned.Interface, namespace
 				return client.ZalandoV1().FabricEventStreams(namespace).Watch(context.TODO(), options)
 			},
 		},
-		&zalandoorgv1.FabricEventStream{},
+		&apiszalandoorgv1.FabricEventStream{},
 		resyncPeriod,
 		indexers,
 	)
@@ -88,9 +88,9 @@ func (f *fabricEventStreamInformer) defaultInformer(client versioned.Interface,
 }
 
 func (f *fabricEventStreamInformer) Informer() cache.SharedIndexInformer {
-	return f.factory.InformerFor(&zalandoorgv1.FabricEventStream{}, f.defaultInformer)
+	return f.factory.InformerFor(&apiszalandoorgv1.FabricEventStream{}, f.defaultInformer)
 }
 
-func (f *fabricEventStreamInformer) Lister() v1.FabricEventStreamLister {
-	return v1.NewFabricEventStreamLister(f.Informer().GetIndexer())
+func (f *fabricEventStreamInformer) Lister() zalandoorgv1.FabricEventStreamLister {
+	return zalandoorgv1.NewFabricEventStreamLister(f.Informer().GetIndexer())
 }