rebase: add controller runtime dependency

this commits add the controller runtime
and its dependency to the vendor.

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>

vendor/sigs.k8s.io/controller-runtime/pkg/leaderelection/doc.go

@@ -0,0 +1,24 @@
+/*
+Copyright 2018 The Kubernetes 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
+
+    http://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.
+*/
+
+/*
+Package leaderelection contains a constructors for a leader election resource lock.
+This is used to ensure that multiple copies of a controller manager can be run with
+only one active set of controllers, for active-passive HA.
+
+It uses built-in Kubernetes leader election APIs.
+*/
+package leaderelection

vendor/sigs.k8s.io/controller-runtime/pkg/leaderelection/leader_election.go

@@ -0,0 +1,111 @@
+/*
+Copyright 2018 The Kubernetes 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
+
+    http://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.
+*/
+
+package leaderelection
+
+import (
+	"errors"
+	"fmt"
+	"io/ioutil"
+	"os"
+
+	"k8s.io/apimachinery/pkg/util/uuid"
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/rest"
+	"k8s.io/client-go/tools/leaderelection/resourcelock"
+	"sigs.k8s.io/controller-runtime/pkg/recorder"
+)
+
+const inClusterNamespacePath = "/var/run/secrets/kubernetes.io/serviceaccount/namespace"
+
+// Options provides the required configuration to create a new resource lock
+type Options struct {
+	// LeaderElection determines whether or not to use leader election when
+	// starting the manager.
+	LeaderElection bool
+
+	// LeaderElectionNamespace determines the namespace in which the leader
+	// election configmap will be created.
+	LeaderElectionNamespace string
+
+	// LeaderElectionID determines the name of the configmap that leader election
+	// will use for holding the leader lock.
+	LeaderElectionID string
+}
+
+// NewResourceLock creates a new config map resource lock for use in a leader
+// election loop
+func NewResourceLock(config *rest.Config, recorderProvider recorder.Provider, options Options) (resourcelock.Interface, error) {
+	if !options.LeaderElection {
+		return nil, nil
+	}
+
+	// LeaderElectionID must be provided to prevent clashes
+	if options.LeaderElectionID == "" {
+		return nil, errors.New("LeaderElectionID must be configured")
+	}
+
+	// Default the namespace (if running in cluster)
+	if options.LeaderElectionNamespace == "" {
+		var err error
+		options.LeaderElectionNamespace, err = getInClusterNamespace()
+		if err != nil {
+			return nil, fmt.Errorf("unable to find leader election namespace: %w", err)
+		}
+	}
+
+	// Leader id, needs to be unique
+	id, err := os.Hostname()
+	if err != nil {
+		return nil, err
+	}
+	id = id + "_" + string(uuid.NewUUID())
+
+	// Construct client for leader election
+	client, err := kubernetes.NewForConfig(config)
+	if err != nil {
+		return nil, err
+	}
+
+	// TODO(JoelSpeed): switch to leaderelection object in 1.12
+	return resourcelock.New(resourcelock.ConfigMapsResourceLock,
+		options.LeaderElectionNamespace,
+		options.LeaderElectionID,
+		client.CoreV1(),
+		client.CoordinationV1(),
+		resourcelock.ResourceLockConfig{
+			Identity:      id,
+			EventRecorder: recorderProvider.GetEventRecorderFor(id),
+		})
+}
+
+func getInClusterNamespace() (string, error) {
+	// Check whether the namespace file exists.
+	// If not, we are not running in cluster so can't guess the namespace.
+	_, err := os.Stat(inClusterNamespacePath)
+	if os.IsNotExist(err) {
+		return "", fmt.Errorf("not running in-cluster, please specify LeaderElectionNamespace")
+	} else if err != nil {
+		return "", fmt.Errorf("error checking namespace file: %w", err)
+	}
+
+	// Load the namespace file and return its content
+	namespace, err := ioutil.ReadFile(inClusterNamespacePath)
+	if err != nil {
+		return "", fmt.Errorf("error reading namespace file: %w", err)
+	}
+	return string(namespace), nil
+}