Add context to EventHandler(s)

This changeset adds a context.Context parameter to every EventHandler
call. Most project might use MapFunc specifically to retrieve other
objects with clients and potentially enqueue requests to a watching
object. A context is useful in these cases to avoid using context.TODO()
or Background() which never gets cancelled.

Signed-off-by: Vince Prignano <[email protected]>

Author: vincepri

pkg/builder/controller_test.go

@@ -497,7 +497,7 @@ var _ = Describe("application", func() {
 				For(&appsv1.Deployment{}, OnlyMetadata).
 				Owns(&appsv1.ReplicaSet{}, OnlyMetadata).
 				Watches(&appsv1.StatefulSet{},
-					handler.EnqueueRequestsFromMapFunc(func(o client.Object) []reconcile.Request {
+					handler.EnqueueRequestsFromMapFunc(func(ctx context.Context, o client.Object) []reconcile.Request {
 						defer GinkgoRecover()
 
 						ometa := o.(*metav1.PartialObjectMetadata)

pkg/handler/enqueue.go

@@ -17,6 +17,8 @@ limitations under the License.
 package handler
 
 import (
+	"context"
+
 	"k8s.io/apimachinery/pkg/types"
 	"k8s.io/client-go/util/workqueue"
 	"sigs.k8s.io/controller-runtime/pkg/event"
@@ -36,7 +38,7 @@ var _ EventHandler = &EnqueueRequestForObject{}
 type EnqueueRequestForObject struct{}
 
 // Create implements EventHandler.
-func (e *EnqueueRequestForObject) Create(evt event.CreateEvent, q workqueue.RateLimitingInterface) {
+func (e *EnqueueRequestForObject) Create(ctx context.Context, evt event.CreateEvent, q workqueue.RateLimitingInterface) {
 	if evt.Object == nil {
 		enqueueLog.Error(nil, "CreateEvent received with no metadata", "event", evt)
 		return
@@ -48,7 +50,7 @@ func (e *EnqueueRequestForObject) Create(evt event.CreateEvent, q workqueue.Rate
 }
 
 // Update implements EventHandler.
-func (e *EnqueueRequestForObject) Update(evt event.UpdateEvent, q workqueue.RateLimitingInterface) {
+func (e *EnqueueRequestForObject) Update(ctx context.Context, evt event.UpdateEvent, q workqueue.RateLimitingInterface) {
 	switch {
 	case evt.ObjectNew != nil:
 		q.Add(reconcile.Request{NamespacedName: types.NamespacedName{
@@ -66,7 +68,7 @@ func (e *EnqueueRequestForObject) Update(evt event.UpdateEvent, q workqueue.Rate
 }
 
 // Delete implements EventHandler.
-func (e *EnqueueRequestForObject) Delete(evt event.DeleteEvent, q workqueue.RateLimitingInterface) {
+func (e *EnqueueRequestForObject) Delete(ctx context.Context, evt event.DeleteEvent, q workqueue.RateLimitingInterface) {
 	if evt.Object == nil {
 		enqueueLog.Error(nil, "DeleteEvent received with no metadata", "event", evt)
 		return
@@ -78,7 +80,7 @@ func (e *EnqueueRequestForObject) Delete(evt event.DeleteEvent, q workqueue.Rate
 }
 
 // Generic implements EventHandler.
-func (e *EnqueueRequestForObject) Generic(evt event.GenericEvent, q workqueue.RateLimitingInterface) {
+func (e *EnqueueRequestForObject) Generic(ctx context.Context, evt event.GenericEvent, q workqueue.RateLimitingInterface) {
 	if evt.Object == nil {
 		enqueueLog.Error(nil, "GenericEvent received with no metadata", "event", evt)
 		return

pkg/handler/enqueue_mapped.go

@@ -17,6 +17,8 @@ limitations under the License.
 package handler
 
 import (
+	"context"
+
 	"k8s.io/client-go/util/workqueue"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 	"sigs.k8s.io/controller-runtime/pkg/event"
@@ -25,7 +27,7 @@ import (
 
 // MapFunc is the signature required for enqueueing requests from a generic function.
 // This type is usually used with EnqueueRequestsFromMapFunc when registering an event handler.
-type MapFunc func(client.Object) []reconcile.Request
+type MapFunc func(context.Context, client.Object) []reconcile.Request
 
 // EnqueueRequestsFromMapFunc enqueues Requests by running a transformation function that outputs a collection
 // of reconcile.Requests on each Event.  The reconcile.Requests may be for an arbitrary set of objects
@@ -51,32 +53,32 @@ type enqueueRequestsFromMapFunc struct {
 }
 
 // Create implements EventHandler.
-func (e *enqueueRequestsFromMapFunc) Create(evt event.CreateEvent, q workqueue.RateLimitingInterface) {
+func (e *enqueueRequestsFromMapFunc) Create(ctx context.Context, evt event.CreateEvent, q workqueue.RateLimitingInterface) {
 	reqs := map[reconcile.Request]empty{}
-	e.mapAndEnqueue(q, evt.Object, reqs)
+	e.mapAndEnqueue(ctx, q, evt.Object, reqs)
 }
 
 // Update implements EventHandler.
-func (e *enqueueRequestsFromMapFunc) Update(evt event.UpdateEvent, q workqueue.RateLimitingInterface) {
+func (e *enqueueRequestsFromMapFunc) Update(ctx context.Context, evt event.UpdateEvent, q workqueue.RateLimitingInterface) {
 	reqs := map[reconcile.Request]empty{}
-	e.mapAndEnqueue(q, evt.ObjectOld, reqs)
-	e.mapAndEnqueue(q, evt.ObjectNew, reqs)
+	e.mapAndEnqueue(ctx, q, evt.ObjectOld, reqs)
+	e.mapAndEnqueue(ctx, q, evt.ObjectNew, reqs)
 }
 
 // Delete implements EventHandler.
-func (e *enqueueRequestsFromMapFunc) Delete(evt event.DeleteEvent, q workqueue.RateLimitingInterface) {
+func (e *enqueueRequestsFromMapFunc) Delete(ctx context.Context, evt event.DeleteEvent, q workqueue.RateLimitingInterface) {
 	reqs := map[reconcile.Request]empty{}
-	e.mapAndEnqueue(q, evt.Object, reqs)
+	e.mapAndEnqueue(ctx, q, evt.Object, reqs)
 }
 
 // Generic implements EventHandler.
-func (e *enqueueRequestsFromMapFunc) Generic(evt event.GenericEvent, q workqueue.RateLimitingInterface) {
+func (e *enqueueRequestsFromMapFunc) Generic(ctx context.Context, evt event.GenericEvent, q workqueue.RateLimitingInterface) {
 	reqs := map[reconcile.Request]empty{}
-	e.mapAndEnqueue(q, evt.Object, reqs)
+	e.mapAndEnqueue(ctx, q, evt.Object, reqs)
 }
 
-func (e *enqueueRequestsFromMapFunc) mapAndEnqueue(q workqueue.RateLimitingInterface, object client.Object, reqs map[reconcile.Request]empty) {
-	for _, req := range e.toRequests(object) {
+func (e *enqueueRequestsFromMapFunc) mapAndEnqueue(ctx context.Context, q workqueue.RateLimitingInterface, object client.Object, reqs map[reconcile.Request]empty) {
+	for _, req := range e.toRequests(ctx, object) {
 		_, ok := reqs[req]
 		if !ok {
 			q.Add(req)

pkg/handler/enqueue_owner.go

@@ -17,6 +17,7 @@ limitations under the License.
 package handler
 
 import (
+	"context"
 	"fmt"
 
 	"k8s.io/apimachinery/pkg/api/meta"
@@ -82,7 +83,7 @@ type enqueueRequestForOwner struct {
 }
 
 // Create implements EventHandler.
-func (e *enqueueRequestForOwner) Create(evt event.CreateEvent, q workqueue.RateLimitingInterface) {
+func (e *enqueueRequestForOwner) Create(ctx context.Context, evt event.CreateEvent, q workqueue.RateLimitingInterface) {
 	reqs := map[reconcile.Request]empty{}
 	e.getOwnerReconcileRequest(evt.Object, reqs)
 	for req := range reqs {
@@ -91,7 +92,7 @@ func (e *enqueueRequestForOwner) Create(evt event.CreateEvent, q workqueue.RateL
 }
 
 // Update implements EventHandler.
-func (e *enqueueRequestForOwner) Update(evt event.UpdateEvent, q workqueue.RateLimitingInterface) {
+func (e *enqueueRequestForOwner) Update(ctx context.Context, evt event.UpdateEvent, q workqueue.RateLimitingInterface) {
 	reqs := map[reconcile.Request]empty{}
 	e.getOwnerReconcileRequest(evt.ObjectOld, reqs)
 	e.getOwnerReconcileRequest(evt.ObjectNew, reqs)
@@ -101,7 +102,7 @@ func (e *enqueueRequestForOwner) Update(evt event.UpdateEvent, q workqueue.RateL
 }
 
 // Delete implements EventHandler.
-func (e *enqueueRequestForOwner) Delete(evt event.DeleteEvent, q workqueue.RateLimitingInterface) {
+func (e *enqueueRequestForOwner) Delete(ctx context.Context, evt event.DeleteEvent, q workqueue.RateLimitingInterface) {
 	reqs := map[reconcile.Request]empty{}
 	e.getOwnerReconcileRequest(evt.Object, reqs)
 	for req := range reqs {
@@ -110,7 +111,7 @@ func (e *enqueueRequestForOwner) Delete(evt event.DeleteEvent, q workqueue.RateL
 }
 
 // Generic implements EventHandler.
-func (e *enqueueRequestForOwner) Generic(evt event.GenericEvent, q workqueue.RateLimitingInterface) {
+func (e *enqueueRequestForOwner) Generic(ctx context.Context, evt event.GenericEvent, q workqueue.RateLimitingInterface) {
 	reqs := map[reconcile.Request]empty{}
 	e.getOwnerReconcileRequest(evt.Object, reqs)
 	for req := range reqs {

pkg/handler/eventhandler.go

@@ -17,6 +17,8 @@ limitations under the License.
 package handler
 
 import (
+	"context"
+
 	"k8s.io/client-go/util/workqueue"
 	"sigs.k8s.io/controller-runtime/pkg/event"
 )
@@ -41,17 +43,17 @@ import (
 // Most users shouldn't need to implement their own EventHandler.
 type EventHandler interface {
 	// Create is called in response to an create event - e.g. Pod Creation.
-	Create(event.CreateEvent, workqueue.RateLimitingInterface)
+	Create(context.Context, event.CreateEvent, workqueue.RateLimitingInterface)
 
 	// Update is called in response to an update event -  e.g. Pod Updated.
-	Update(event.UpdateEvent, workqueue.RateLimitingInterface)
+	Update(context.Context, event.UpdateEvent, workqueue.RateLimitingInterface)
 
 	// Delete is called in response to a delete event - e.g. Pod Deleted.
-	Delete(event.DeleteEvent, workqueue.RateLimitingInterface)
+	Delete(context.Context, event.DeleteEvent, workqueue.RateLimitingInterface)
 
 	// Generic is called in response to an event of an unknown type or a synthetic event triggered as a cron or
 	// external trigger request - e.g. reconcile Autoscaling, or a Webhook.
-	Generic(event.GenericEvent, workqueue.RateLimitingInterface)
+	Generic(context.Context, event.GenericEvent, workqueue.RateLimitingInterface)
 }
 
 var _ EventHandler = Funcs{}
@@ -60,45 +62,45 @@ var _ EventHandler = Funcs{}
 type Funcs struct {
 	// Create is called in response to an add event.  Defaults to no-op.
 	// RateLimitingInterface is used to enqueue reconcile.Requests.
-	CreateFunc func(event.CreateEvent, workqueue.RateLimitingInterface)
+	CreateFunc func(context.Context, event.CreateEvent, workqueue.RateLimitingInterface)
 
 	// Update is called in response to an update event.  Defaults to no-op.
 	// RateLimitingInterface is used to enqueue reconcile.Requests.
-	UpdateFunc func(event.UpdateEvent, workqueue.RateLimitingInterface)
+	UpdateFunc func(context.Context, event.UpdateEvent, workqueue.RateLimitingInterface)
 
 	// Delete is called in response to a delete event.  Defaults to no-op.
 	// RateLimitingInterface is used to enqueue reconcile.Requests.
-	DeleteFunc func(event.DeleteEvent, workqueue.RateLimitingInterface)
+	DeleteFunc func(context.Context, event.DeleteEvent, workqueue.RateLimitingInterface)
 
 	// GenericFunc is called in response to a generic event.  Defaults to no-op.
 	// RateLimitingInterface is used to enqueue reconcile.Requests.
-	GenericFunc func(event.GenericEvent, workqueue.RateLimitingInterface)
+	GenericFunc func(context.Context, event.GenericEvent, workqueue.RateLimitingInterface)
 }
 
 // Create implements EventHandler.
-func (h Funcs) Create(e event.CreateEvent, q workqueue.RateLimitingInterface) {
+func (h Funcs) Create(ctx context.Context, e event.CreateEvent, q workqueue.RateLimitingInterface) {
 	if h.CreateFunc != nil {
-		h.CreateFunc(e, q)
+		h.CreateFunc(ctx, e, q)
 	}
 }
 
 // Delete implements EventHandler.
-func (h Funcs) Delete(e event.DeleteEvent, q workqueue.RateLimitingInterface) {
+func (h Funcs) Delete(ctx context.Context, e event.DeleteEvent, q workqueue.RateLimitingInterface) {
 	if h.DeleteFunc != nil {
-		h.DeleteFunc(e, q)
+		h.DeleteFunc(ctx, e, q)
 	}
 }
 
 // Update implements EventHandler.
-func (h Funcs) Update(e event.UpdateEvent, q workqueue.RateLimitingInterface) {
+func (h Funcs) Update(ctx context.Context, e event.UpdateEvent, q workqueue.RateLimitingInterface) {
 	if h.UpdateFunc != nil {
-		h.UpdateFunc(e, q)
+		h.UpdateFunc(ctx, e, q)
 	}
 }
 
 // Generic implements EventHandler.
-func (h Funcs) Generic(e event.GenericEvent, q workqueue.RateLimitingInterface) {
+func (h Funcs) Generic(ctx context.Context, e event.GenericEvent, q workqueue.RateLimitingInterface) {
 	if h.GenericFunc != nil {
-		h.GenericFunc(e, q)
+		h.GenericFunc(ctx, e, q)
 	}
 }