Add leader election

Gopkg.toml

@@ -54,7 +54,7 @@ required = [
 
 [[override]]
   name = "knative.dev/pkg"
-  branch = "release-0.12"
+  branch = "release-0.13"
 
 [[override]]
   name = "knative.dev/test-infra"

cmd/manager/main.go

@@ -31,5 +31,5 @@ func main() {
 	if err != nil {
 		log.Fatal("Error building kubeconfig", err)
 	}
-	sharedmain.MainWithConfig(signals.NewContext(), "serving_operator", cfg, knativeserving.NewController)
+	sharedmain.MainWithConfig(signals.NewContext(), "serving-operator", cfg, knativeserving.NewController)
 }

config/config-leader-election.yaml

@@ -0,0 +1,64 @@
+# Copyright 2020 The Knative Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: config-leader-election
+  labels:
+    serving.knative.dev/release: devel
+data:
+  # An inactive but valid configuration follows; see example.
+  resourceLock: "leases"
+  leaseDuration: "15s"
+  renewDeadline: "10s"
+  retryPeriod: "2s"
+  _example: |
+    ################################
+    #                              #
+    #    EXAMPLE CONFIGURATION     #
+    #                              #
+    ################################
+
+    # This block is not actually functional configuration,
+    # but serves to illustrate the available configuration
+    # options and document them in a way that is accessible
+    # to users that `kubectl edit` this config map.
+    #
+    # These sample configuration options may be copied out of
+    # this example block and unindented to be in the data block
+    # to actually change the configuration.
+
+    # resourceLock controls which API resource is used as the basis for the
+    # leader election lock. Valid values are:
+    #
+    # - leases -> use the coordination API
+    # - configmaps -> use configmaps
+    # - endpoints -> use endpoints
+    resourceLock: "leases"
+
+    # leaseDuration is how long non-leaders will wait to try to acquire the
+    # lock; 15 seconds is the value used by core kubernetes controllers.
+    leaseDuration: "15s"
+    # renewDeadline is how long a leader will try to renew the lease before
+    # giving up; 10 seconds is the value used by core kubernetes controllers.
+    renewDeadline: "10s"
+    # retryPeriod is how long the leader election client waits between tries of
+    # actions; 2 seconds is the value used by core kubernetes controllers.
+    retryPeriod: "2s"
+    # enabledComponents is a comma-delimited list of component names for which
+    # leader election is enabled. Valid values are:
+    #
+    # - serving-operator
+    enabledComponents: "serving-operator"

config/role.yaml

@@ -52,6 +52,12 @@ rules:
   - '*'
   verbs:
   - '*'
+- apiGroups:
+  - coordination.k8s.io
+  resources:
+  - leases
+  verbs:
+  - '*'
 ---
 kind: ClusterRole
 apiVersion: rbac.authorization.k8s.io/v1