✨ Add controller workqueue option

pkg/controller/controller.go

@@ -59,6 +59,18 @@ type Options struct {
 	// The overall is a token bucket and the per-item is exponential.
 	RateLimiter ratelimiter.RateLimiter
 
+	// NewQueue constructs the queue for this controller once the controller is ready to start.
+	// With NewQueue a custom queue implementation can be used, e.g. a priority queue to prioritize with which
+	// priority/order objects are reconciled (e.g. to reconcile objects with changes first).
+	// This is a func because the standard Kubernetes work queues start themselves immediately, which
+	// leads to goroutine leaks if something calls controller.New repeatedly.
+	// The NewQueue func gets the controller name and the RateLimiter option (defaulted if necessary) passed in.
+	// NewQueue defaults to NewRateLimitingQueueWithConfig.
+	//
+	// NOTE: LOW LEVEL PRIMITIVE!
+	// Only use a custom NewQueue if you know what you are doing.
+	NewQueue func(controllerName string, rateLimiter ratelimiter.RateLimiter) workqueue.RateLimitingInterface
+
 	// LogConstructor is used to construct a logger used for this controller and passed
 	// to each reconciliation via the context field.
 	LogConstructor func(request *reconcile.Request) logr.Logger
@@ -147,6 +159,14 @@ func NewUnmanaged(name string, mgr manager.Manager, options Options) (Controller
 		options.RateLimiter = workqueue.DefaultControllerRateLimiter()
 	}
 
+	if options.NewQueue == nil {
+		options.NewQueue = func(controllerName string, rateLimiter ratelimiter.RateLimiter) workqueue.RateLimitingInterface {
+			return workqueue.NewRateLimitingQueueWithConfig(rateLimiter, workqueue.RateLimitingQueueConfig{
+				Name: controllerName,
+			})
+		}
+	}
+
 	if options.RecoverPanic == nil {
 		options.RecoverPanic = mgr.GetControllerOptions().RecoverPanic
 	}
@@ -157,12 +177,9 @@ func NewUnmanaged(name string, mgr manager.Manager, options Options) (Controller
 
 	// Create controller with dependencies set
 	return &controller.Controller{
-		Do: options.Reconciler,
-		MakeQueue: func() workqueue.RateLimitingInterface {
-			return workqueue.NewRateLimitingQueueWithConfig(options.RateLimiter, workqueue.RateLimitingQueueConfig{
-				Name: name,
-			})
-		},
+		Do:                      options.Reconciler,
+		RateLimiter:             options.RateLimiter,
+		NewQueue:                options.NewQueue,
 		MaxConcurrentReconciles: options.MaxConcurrentReconciles,
 		CacheSyncTimeout:        options.CacheSyncTimeout,
 		Name:                    name,

pkg/controller/controller_test.go

@@ -24,6 +24,7 @@ import (
 	. "github.com/onsi/gomega"
 	"go.uber.org/goleak"
 	corev1 "k8s.io/api/core/v1"
+	"k8s.io/client-go/util/workqueue"
 	"k8s.io/utils/ptr"
 
 	"sigs.k8s.io/controller-runtime/pkg/config"
@@ -32,6 +33,7 @@ import (
 	"sigs.k8s.io/controller-runtime/pkg/handler"
 	internalcontroller "sigs.k8s.io/controller-runtime/pkg/internal/controller"
 	"sigs.k8s.io/controller-runtime/pkg/manager"
+	"sigs.k8s.io/controller-runtime/pkg/ratelimiter"
 	"sigs.k8s.io/controller-runtime/pkg/reconcile"
 	"sigs.k8s.io/controller-runtime/pkg/source"
 )
@@ -133,6 +135,48 @@ var _ = Describe("controller.Controller", func() {
 			Eventually(func() error { return goleak.Find(currentGRs) }).Should(Succeed())
 		})
 
+		It("should default RateLimiter and NewQueue if not specified", func() {
+			m, err := manager.New(cfg, manager.Options{})
+			Expect(err).NotTo(HaveOccurred())
+
+			c, err := controller.New("new-controller", m, controller.Options{
+				Reconciler: reconcile.Func(nil),
+			})
+			Expect(err).NotTo(HaveOccurred())
+
+			ctrl, ok := c.(*internalcontroller.Controller)
+			Expect(ok).To(BeTrue())
+
+			Expect(ctrl.RateLimiter).NotTo(BeNil())
+			Expect(ctrl.NewQueue).NotTo(BeNil())
+		})
+
+		It("should not override RateLimiter and NewQueue if specified", func() {
+			m, err := manager.New(cfg, manager.Options{})
+			Expect(err).NotTo(HaveOccurred())
+
+			customRateLimiter := workqueue.NewItemExponentialFailureRateLimiter(5*time.Millisecond, 1000*time.Second)
+			customNewQueueCalled := false
+			customNewQueue := func(controllerName string, rateLimiter ratelimiter.RateLimiter) workqueue.RateLimitingInterface {
+				customNewQueueCalled = true
+				return nil
+			}
+
+			c, err := controller.New("new-controller", m, controller.Options{
+				Reconciler:  reconcile.Func(nil),
+				RateLimiter: customRateLimiter,
+				NewQueue:    customNewQueue,
+			})
+			Expect(err).NotTo(HaveOccurred())
+
+			ctrl, ok := c.(*internalcontroller.Controller)
+			Expect(ok).To(BeTrue())
+
+			Expect(ctrl.RateLimiter).To(BeIdenticalTo(customRateLimiter))
+			ctrl.NewQueue("controller1", nil)
+			Expect(customNewQueueCalled).To(BeTrue(), "Expected customNewQueue to be called")
+		})
+
 		It("should default RecoverPanic from the manager", func() {
 			m, err := manager.New(cfg, manager.Options{Controller: config.Controller{RecoverPanic: ptr.To(true)}})
 			Expect(err).NotTo(HaveOccurred())

pkg/internal/controller/controller.go

@@ -33,6 +33,7 @@ import (
 	ctrlmetrics "sigs.k8s.io/controller-runtime/pkg/internal/controller/metrics"
 	logf "sigs.k8s.io/controller-runtime/pkg/log"
 	"sigs.k8s.io/controller-runtime/pkg/predicate"
+	"sigs.k8s.io/controller-runtime/pkg/ratelimiter"
 	"sigs.k8s.io/controller-runtime/pkg/reconcile"
 	"sigs.k8s.io/controller-runtime/pkg/source"
 )
@@ -50,10 +51,13 @@ type Controller struct {
 	// Defaults to the DefaultReconcileFunc.
 	Do reconcile.Reconciler
 
-	// MakeQueue constructs the queue for this controller once the controller is ready to start.
-	// This exists because the standard Kubernetes workqueues start themselves immediately, which
+	// RateLimiter is used to limit how frequently requests may be queued into the work queue.
+	RateLimiter ratelimiter.RateLimiter
+
+	// NewQueue constructs the queue for this controller once the controller is ready to start.
+	// This is a func because the standard Kubernetes work queues start themselves immediately, which
 	// leads to goroutine leaks if something calls controller.New repeatedly.
-	MakeQueue func() workqueue.RateLimitingInterface
+	NewQueue func(controllerName string, rateLimiter ratelimiter.RateLimiter) workqueue.RateLimitingInterface
 
 	// Queue is an listeningQueue that listens for events from Informers and adds object keys to
 	// the Queue for processing
@@ -158,7 +162,7 @@ func (c *Controller) Start(ctx context.Context) error {
 	// Set the internal context.
 	c.ctx = ctx
 
-	c.Queue = c.MakeQueue()
+	c.Queue = c.NewQueue(c.Name, c.RateLimiter)
 	go func() {
 		<-ctx.Done()
 		c.Queue.ShutDown()

pkg/internal/controller/controller_test.go

@@ -43,6 +43,7 @@ import (
 	ctrlmetrics "sigs.k8s.io/controller-runtime/pkg/internal/controller/metrics"
 	"sigs.k8s.io/controller-runtime/pkg/internal/log"
 	"sigs.k8s.io/controller-runtime/pkg/predicate"
+	"sigs.k8s.io/controller-runtime/pkg/ratelimiter"
 	"sigs.k8s.io/controller-runtime/pkg/reconcile"
 	"sigs.k8s.io/controller-runtime/pkg/source"
 )
@@ -68,7 +69,7 @@ var _ = Describe("controller", func() {
 		ctrl = &Controller{
 			MaxConcurrentReconciles: 1,
 			Do:                      fakeReconcile,
-			MakeQueue:               func() workqueue.RateLimitingInterface { return queue },
+			NewQueue:                func(string, ratelimiter.RateLimiter) workqueue.RateLimitingInterface { return queue },
 			LogConstructor: func(_ *reconcile.Request) logr.Logger {
 				return log.RuntimeLog.WithName("controller").WithName("test")
 			},
@@ -408,8 +409,8 @@ var _ = Describe("controller", func() {
 		// TODO(directxman12): we should ensure that backoff occurrs with error requeue
 
 		It("should not reset backoff until there's a non-error result", func() {
-			dq := &DelegatingQueue{RateLimitingInterface: ctrl.MakeQueue()}
-			ctrl.MakeQueue = func() workqueue.RateLimitingInterface { return dq }
+			dq := &DelegatingQueue{RateLimitingInterface: ctrl.NewQueue("controller1", nil)}
+			ctrl.NewQueue = func(string, ratelimiter.RateLimiter) workqueue.RateLimitingInterface { return dq }
 
 			ctx, cancel := context.WithCancel(context.Background())
 			defer cancel()
@@ -444,8 +445,8 @@ var _ = Describe("controller", func() {
 		})
 
 		It("should requeue a Request with rate limiting if the Result sets Requeue:true and continue processing items", func() {
-			dq := &DelegatingQueue{RateLimitingInterface: ctrl.MakeQueue()}
-			ctrl.MakeQueue = func() workqueue.RateLimitingInterface { return dq }
+			dq := &DelegatingQueue{RateLimitingInterface: ctrl.NewQueue("controller1", nil)}
+			ctrl.NewQueue = func(string, ratelimiter.RateLimiter) workqueue.RateLimitingInterface { return dq }
 
 			ctx, cancel := context.WithCancel(context.Background())
 			defer cancel()
@@ -474,8 +475,8 @@ var _ = Describe("controller", func() {
 		})
 
 		It("should requeue a Request after a duration (but not rate-limitted) if the Result sets RequeueAfter (regardless of Requeue)", func() {
-			dq := &DelegatingQueue{RateLimitingInterface: ctrl.MakeQueue()}
-			ctrl.MakeQueue = func() workqueue.RateLimitingInterface { return dq }
+			dq := &DelegatingQueue{RateLimitingInterface: ctrl.NewQueue("controller1", nil)}
+			ctrl.NewQueue = func(string, ratelimiter.RateLimiter) workqueue.RateLimitingInterface { return dq }
 
 			ctx, cancel := context.WithCancel(context.Background())
 			defer cancel()
@@ -504,8 +505,8 @@ var _ = Describe("controller", func() {
 		})
 
 		It("should perform error behavior if error is not nil, regardless of RequeueAfter", func() {
-			dq := &DelegatingQueue{RateLimitingInterface: ctrl.MakeQueue()}
-			ctrl.MakeQueue = func() workqueue.RateLimitingInterface { return dq }
+			dq := &DelegatingQueue{RateLimitingInterface: ctrl.NewQueue("controller1", nil)}
+			ctrl.NewQueue = func(string, ratelimiter.RateLimiter) workqueue.RateLimitingInterface { return dq }
 
 			ctx, cancel := context.WithCancel(context.Background())
 			defer cancel()