⚠ Change leaderlock from ConfigMap to ConfigMapsLeasesResourceLock

This commit changes the leaderlock to ConfigMapsLeasesResourceLock,
which is intended to transition ppl from the ConfigMap to the more
modern Leases. It is breaking because additional RBAC is required.

Author: alvaroaleman

pkg/leaderelection/leader_election.go

@@ -81,7 +81,7 @@ func NewResourceLock(config *rest.Config, recorderProvider recorder.Provider, op
 	}
 
 	// TODO(JoelSpeed): switch to leaderelection object in 1.12
-	return resourcelock.New(resourcelock.ConfigMapsResourceLock,
+	return resourcelock.New(resourcelock.ConfigMapsLeasesResourceLock,
 		options.LeaderElectionNamespace,
 		options.LeaderElectionID,
 		client.CoreV1(),

pkg/manager/manager_test.go

@@ -302,6 +302,24 @@ var _ = Describe("manger.Manager", func() {
 				Expect(err).To(HaveOccurred())
 				Expect(err.Error()).To(ContainSubstring("unable to find leader election namespace: not running in-cluster, please specify LeaderElectionNamespace"))
 			})
+
+			// We must keep this default until we are sure all controller-runtime users have upgraded from the original default
+			// ConfigMap lock to a controller-runtime version that has this new default. Many users of controller-runtime skip
+			// versions, so we should be extremely conservative here.
+			It("should default to ConfigMapsLeasesResourceLock", func() {
+				m, err := New(cfg, Options{LeaderElection: true, LeaderElectionID: "controller-runtime", LeaderElectionNamespace: "my-ns"})
+				Expect(m).ToNot(BeNil())
+				Expect(err).ToNot(HaveOccurred())
+				cm, ok := m.(*controllerManager)
+				Expect(ok).To(BeTrue())
+				multilock, isMultiLock := cm.resourceLock.(*resourcelock.MultiLock)
+				Expect(isMultiLock).To(BeTrue())
+				_, primaryIsConfigMapLock := multilock.Primary.(*resourcelock.ConfigMapLock)
+				Expect(primaryIsConfigMapLock).To(BeTrue())
+				_, secondaryIsLeaseLock := multilock.Secondary.(*resourcelock.LeaseLock)
+				Expect(secondaryIsLeaseLock).To(BeTrue())
+
+			})
 		})
 
 		It("should create a listener for the metrics if a valid address is provided", func() {