plugin/metrics: Switch to using promhttp instead of deprecated Handler (#1312)

prometheus.Handler is deprecated according to the godoc for the package so
instead we're using promhttp.

Additionally, we are exposing the Registry that metrics is using so other
plugins that are not inside of coredns can read the registry. Otherwise, if
we kept using the Default one, there's no way to access that from outside
of the coredns repo since it is vendored.

vendor/k8s.io/client-go/examples/README.md

@@ -0,0 +1,31 @@
+# client-go Examples
+
+This directory contains examples that cover various use cases and functionality
+for client-go.
+
+### Configuration
+
+- [**Authenticate in cluster**](./in-cluster-client-configuration): Configure a
+  client while running inside the Kubernetes cluster.
+- [**Authenticate out of cluster**](./out-of-cluster-client-configuration):
+  Configure a client to access a Kubernetes cluster from outside.
+
+### Basics
+
+- [**Managing resources with API**](./create-update-delete-deployment): Create,
+  get, update, delete a Deployment resource.
+
+### Advanced Concepts
+
+- [**Work queues**](./workqueue): Create a hotloop-free controller with the
+  rate-limited workqueue and the [informer framework][informer].
+- [**Third-party resources (deprecated)**](./third-party-resources-deprecated):
+  Register a third-party resource type with the API, create/update/query this third-party
+  type, and write a controller that drives the cluster state based on the changes to
+  the third-party resources.
+- [**Custom Resource Definition (successor of TPR)**](https://git.k8s.io/apiextensions-apiserver/examples/client-go):
+  Register a custom resource type with the API, create/update/query this custom
+  type, and write a controller that drives the cluster state based on the changes to
+  the custom resources.
+
+[informer]: https://godoc.org/k8s.io/client-go/tools/cache#NewInformer

vendor/k8s.io/client-go/examples/create-update-delete-deployment/BUILD

@@ -0,0 +1,29 @@
+package(default_visibility = ["//visibility:public"])
+
+licenses(["notice"])
+
+load(
+    "@io_bazel_rules_go//go:def.bzl",
+    "go_binary",
+    "go_library",
+)
+
+go_binary(
+    name = "create-update-delete-deployment",
+    library = ":go_default_library",
+    tags = ["automanaged"],
+)
+
+go_library(
+    name = "go_default_library",
+    srcs = ["main.go"],
+    tags = ["automanaged"],
+    deps = [
+        "//vendor/k8s.io/apimachinery/pkg/api/errors:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
+        "//vendor/k8s.io/client-go/kubernetes:go_default_library",
+        "//vendor/k8s.io/client-go/pkg/api/v1:go_default_library",
+        "//vendor/k8s.io/client-go/pkg/apis/apps/v1beta1:go_default_library",
+        "//vendor/k8s.io/client-go/tools/clientcmd:go_default_library",
+    ],
+)

vendor/k8s.io/client-go/examples/create-update-delete-deployment/README.md

@@ -0,0 +1,81 @@
+# Create, Update & Delete Deployment
+
+This example program demonstrates the fundamental operations for managing on
+[Deployment][1] resources, such as `Create`, `List`, `Update` and `Delete`.
+
+You can adopt the source code from this example to write programs that manage
+other types of resources through the Kubernetes API.
+
+## Running this example
+
+Make sure you have a Kubernetes cluster and `kubectl` is configured:
+
+    kubectl get nodes
+
+Compile this example on your workstation:
+
+```
+cd create-update-delete-deployment
+go build -o ./app
+```
+
+Now, run this application on your workstation with your local kubeconfig file:
+
+```
+./app -kubeconfig=$HOME/.kube/config
+```
+
+Running this command will execute the following operations on your cluster:
+
+1. **Create Deployment:** This will create a 2 replica Deployment. Verify with
+   `kubectl get pods`.
+2. **Update Deployment:** This will update the Deployment resource created in
+   previous step to set the replica count to 1 and add annotations. You are
+   encouraged to inspect the retry loop that handles conflicts. Verify the new
+   replica count and `foo=bar` annotation with `kubectl describe deployment
+   demo`.
+3. **List Deployments:** This will retrieve Deployments in the `default`
+   namespace and print their names and replica counts.
+4. **Delete Deployment:** This will delete the Deployment object and its
+   dependent ReplicaSet resource. Verify with `kubectl get deployments`.
+
+Each step is separated by an interactive prompt. You must hit the
+<kbd>Return</kbd> key to proceeed to the next step. You can use these prompts as
+a break to take time to  run `kubectl` and inspect the result of the operations
+executed.
+
+You should see an output like the following:
+
+```
+Creating deployment...
+Created deployment "demo-deployment".
+-> Press Return key to continue.
+
+Updating deployment...
+Updated deployment...
+-> Press Return key to continue.
+
+Listing deployments in namespace "default":
+ * demo-deployment (1 replicas)
+-> Press Return key to continue.
+
+Deleting deployment...
+Deleted deployment.
+```
+
+## Cleanup
+
+Successfully running this program will clean the created artifacts. If you
+terminate the program without completing, you can clean up the created
+deployment with:
+
+    kubectl delete deploy demo-deployment
+
+## Troubleshooting
+
+If you are getting the following error, make sure Kubernetes version of your
+cluster is v1.6 or above in `kubectl version`:
+
+    panic: the server could not find the requested resource
+
+[1]: https://kubernetes.io/docs/user-guide/deployments/

vendor/k8s.io/client-go/examples/create-update-delete-deployment/main.go

@@ -0,0 +1,165 @@
+/*
+Copyright 2017 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.
+*/
+
+// Note: the example only works with the code within the same release/branch.
+package main
+
+import (
+	"bufio"
+	"flag"
+	"fmt"
+	"os"
+
+	"k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/client-go/kubernetes"
+	apiv1 "k8s.io/client-go/pkg/api/v1"
+	appsv1beta1 "k8s.io/client-go/pkg/apis/apps/v1beta1"
+	"k8s.io/client-go/tools/clientcmd"
+	// Uncomment the following line to load the gcp plugin (only required to authenticate against GKE clusters).
+	// _ "k8s.io/client-go/plugin/pkg/client/auth/gcp"
+)
+
+func main() {
+	kubeconfig := flag.String("kubeconfig", "", "absolute path to the kubeconfig file")
+	flag.Parse()
+	if *kubeconfig == "" {
+		panic("-kubeconfig not specified")
+	}
+	config, err := clientcmd.BuildConfigFromFlags("", *kubeconfig)
+	if err != nil {
+		panic(err)
+	}
+	clientset, err := kubernetes.NewForConfig(config)
+	if err != nil {
+		panic(err)
+	}
+
+	deploymentsClient := clientset.AppsV1beta1().Deployments(apiv1.NamespaceDefault)
+
+	deployment := &appsv1beta1.Deployment{
+		ObjectMeta: metav1.ObjectMeta{
+			Name: "demo-deployment",
+		},
+		Spec: appsv1beta1.DeploymentSpec{
+			Replicas: int32Ptr(2),
+			Template: apiv1.PodTemplateSpec{
+				ObjectMeta: metav1.ObjectMeta{
+					Labels: map[string]string{
+						"app": "demo",
+					},
+				},
+				Spec: apiv1.PodSpec{
+					Containers: []apiv1.Container{
+						{
+							Name:  "web",
+							Image: "nginx:1.13",
+							Ports: []apiv1.ContainerPort{
+								{
+									Name:          "http",
+									Protocol:      apiv1.ProtocolTCP,
+									ContainerPort: 80,
+								},
+							},
+						},
+					},
+				},
+			},
+		},
+	}
+
+	// Create Deployment
+	fmt.Println("Creating deployment...")
+	result, err := deploymentsClient.Create(deployment)
+	if err != nil {
+		panic(err)
+	}
+	fmt.Printf("Created deployment %q.\n", result.GetObjectMeta().GetName())
+
+	// Update Deployment
+	prompt()
+	fmt.Println("Updating deployment...")
+	//    You have two options to Update() this Deployment:
+	//
+	//    1. Modify the "deployment" variable and call: Update(deployment).
+	//       This works like the "kubectl replace" command and it overwrites/loses changes
+	//       made by other clients between you Create() and Update() the object.
+	//    2. Modify the "result" returned by Create()/Get() and retry Update(result) until
+	//       you no longer get a conflict error. This way, you can preserve changes made
+	//       by other clients between Create() and Update(). This is implemented below:
+
+	for {
+		result.Spec.Replicas = int32Ptr(1)                    // reduce replica count
+		result.Spec.Template.Annotations = map[string]string{ // add annotations
+			"foo": "bar",
+		}
+
+		if _, err := deploymentsClient.Update(result); errors.IsConflict(err) {
+			// Deployment is modified in the meanwhile, query the latest version
+			// and modify the retrieved object.
+			fmt.Println("encountered conflict, retrying")
+			result, err = deploymentsClient.Get("demo-deployment", metav1.GetOptions{})
+			if err != nil {
+				panic(fmt.Errorf("Get failed: %+v", err))
+			}
+		} else if err != nil {
+			panic(err)
+		} else {
+			break
+		}
+
+		// TODO: You should sleep here with an exponential backoff to avoid
+		// exhausting the apiserver, and add a limit/timeout on the retries to
+		// avoid getting stuck in this loop indefintiely.
+	}
+	fmt.Println("Updated deployment...")
+
+	// List Deployments
+	prompt()
+	fmt.Printf("Listing deployments in namespace %q:\n", apiv1.NamespaceDefault)
+	list, err := deploymentsClient.List(metav1.ListOptions{})
+	if err != nil {
+		panic(err)
+	}
+	for _, d := range list.Items {
+		fmt.Printf(" * %s (%d replicas)\n", d.Name, *d.Spec.Replicas)
+	}
+
+	// Delete Deployment
+	prompt()
+	fmt.Println("Deleting deployment...")
+	deletePolicy := metav1.DeletePropagationForeground
+	if err := deploymentsClient.Delete("demo-deployment", &metav1.DeleteOptions{
+		PropagationPolicy: &deletePolicy,
+	}); err != nil {
+		panic(err)
+	}
+	fmt.Println("Deleted deployment.")
+}
+
+func prompt() {
+	fmt.Printf("-> Press Return key to continue.")
+	scanner := bufio.NewScanner(os.Stdin)
+	for scanner.Scan() {
+		break
+	}
+	if err := scanner.Err(); err != nil {
+		panic(err)
+	}
+	fmt.Println()
+}
+
+func int32Ptr(i int32) *int32 { return &i }

vendor/k8s.io/client-go/examples/in-cluster-client-configuration/BUILD

@@ -0,0 +1,27 @@
+package(default_visibility = ["//visibility:public"])
+
+licenses(["notice"])
+
+load(
+    "@io_bazel_rules_go//go:def.bzl",
+    "go_binary",
+    "go_library",
+)
+
+go_binary(
+    name = "in-cluster-client-configuration",
+    library = ":go_default_library",
+    tags = ["automanaged"],
+)
+
+go_library(
+    name = "go_default_library",
+    srcs = ["main.go"],
+    tags = ["automanaged"],
+    deps = [
+        "//vendor/k8s.io/apimachinery/pkg/api/errors:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
+        "//vendor/k8s.io/client-go/kubernetes:go_default_library",
+        "//vendor/k8s.io/client-go/rest:go_default_library",
+    ],
+)

vendor/k8s.io/client-go/examples/in-cluster-client-configuration/Dockerfile

@@ -0,0 +1,17 @@
+# Copyright 2017 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.
+
+FROM debian
+COPY ./app /app
+ENTRYPOINT /app

vendor/k8s.io/client-go/examples/in-cluster-client-configuration/README.md

@@ -0,0 +1,50 @@
+# Authenticating inside the cluster
+
+This example shows you how to configure a client with client-go to authenticate
+to the Kubernetes API from an application running inside the Kubernetes cluster.
+
+client-go uses the [Service Account token][sa] mounted inside the Pod at the
+`/var/run/secrets/kubernetes.io/serviceaccount` path when the
+`rest.InClusterConfig()` is used.
+
+## Running this example
+
+First compile the application for Linux:
+
+    cd in-cluster-client-configuration
+    GOOS=linux go build -o ./app .
+
+Then package it to a docker image using the provided Dockerfile to run it on
+Kubernetes.
+
+If you are running a [Minikube][mk] cluster, you can build this image directly
+on the Docker engine of the Minikube node without pushing it to a registry. To
+build the image on Minikube:
+
+    eval $(minikube docker-env)
+    docker build -t in-cluster .
+
+If you are not using Minikube, you should build this image and push it to a registry
+that your Kubernetes cluster can pull from.
+
+Then, run the image in a Pod with a single instance Deployment:
+
+    $ kubectl run --rm -i demo --image=in-cluster --image-pull-policy=Never
+
+    There are 4 pods in the cluster
+    There are 4 pods in the cluster
+    There are 4 pods in the cluster
+    ...
+
+The example now runs on Kubernetes API and successfully queries the number of
+pods in the cluster every 10 seconds.
+
+### Clean up
+
+To stop this example and clean up the pod, press <kbd>Ctrl</kbd>+<kbd>C</kbd> on
+the `kubectl run` command and then run:
+
+    kubectl delete deployment demo
+
+[sa]: https://kubernetes.io/docs/admin/authentication/#service-account-tokens
+[mk]: https://kubernetes.io/docs/getting-started-guides/minikube/

vendor/k8s.io/client-go/examples/in-cluster-client-configuration/main.go

@@ -0,0 +1,64 @@
+/*
+Copyright 2016 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.
+*/
+
+// Note: the example only works with the code within the same release/branch.
+package main
+
+import (
+	"fmt"
+	"time"
+
+	"k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/rest"
+)
+
+func main() {
+	// creates the in-cluster config
+	config, err := rest.InClusterConfig()
+	if err != nil {
+		panic(err.Error())
+	}
+	// creates the clientset
+	clientset, err := kubernetes.NewForConfig(config)
+	if err != nil {
+		panic(err.Error())
+	}
+	for {
+		pods, err := clientset.CoreV1().Pods("").List(metav1.ListOptions{})
+		if err != nil {
+			panic(err.Error())
+		}
+		fmt.Printf("There are %d pods in the cluster\n", len(pods.Items))
+
+		// Examples for error handling:
+		// - Use helper functions like e.g. errors.IsNotFound()
+		// - And/or cast to StatusError and use its properties like e.g. ErrStatus.Message
+		_, err = clientset.CoreV1().Pods("default").Get("example-xxxxx", metav1.GetOptions{})
+		if errors.IsNotFound(err) {
+			fmt.Printf("Pod not found\n")
+		} else if statusError, isStatus := err.(*errors.StatusError); isStatus {
+			fmt.Printf("Error getting pod %v\n", statusError.ErrStatus.Message)
+		} else if err != nil {
+			panic(err.Error())
+		} else {
+			fmt.Printf("Found pod\n")
+		}
+
+		time.Sleep(10 * time.Second)
+	}
+}

vendor/k8s.io/client-go/examples/out-of-cluster-client-configuration/BUILD

@@ -0,0 +1,27 @@
+package(default_visibility = ["//visibility:public"])
+
+licenses(["notice"])
+
+load(
+    "@io_bazel_rules_go//go:def.bzl",
+    "go_binary",
+    "go_library",
+)
+
+go_binary(
+    name = "out-of-cluster-client-configuration",
+    library = ":go_default_library",
+    tags = ["automanaged"],
+)
+
+go_library(
+    name = "go_default_library",
+    srcs = ["main.go"],
+    tags = ["automanaged"],
+    deps = [
+        "//vendor/k8s.io/apimachinery/pkg/api/errors:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
+        "//vendor/k8s.io/client-go/kubernetes:go_default_library",
+        "//vendor/k8s.io/client-go/tools/clientcmd:go_default_library",
+    ],
+)

vendor/k8s.io/client-go/examples/out-of-cluster-client-configuration/README.md

@@ -0,0 +1,35 @@
+# Authenticating outside the cluster
+
+This example shows you how to configure a client with client-go to authenticate
+to the Kubernetes API from an application running outside the Kubernetes
+cluster.
+
+You can use your kubeconfig file that contains the context information
+of your cluster to initialize a client. The kubeconfig file is also used
+by the `kubectl` command to authenticate to the clusters.
+
+## Running this example
+
+Make sure your `kubectl` is configured and pointed to a cluster. Run
+`kubectl get nodes` to confirm.
+
+Run this application with:
+
+    cd out-of-cluster-client-configuration
+    go build -o app .
+    ./app
+
+Running this application will use the kubeconfig file and then authenticate to the
+cluster, and print the number of nodes in the cluster every 10 seconds:
+
+    $ ./app
+    There are 3 pods in the cluster
+    There are 3 pods in the cluster
+    There are 3 pods in the cluster
+    ...
+
+Press <kbd>Ctrl</kbd>+<kbd>C</kbd> to quit this application.
+
+> **Note:** You can use the `-kubeconfig` option to use a different config file. By default
+this program picks up the default file used by kubectl (when `KUBECONFIG`
+environment variable is not set).

vendor/k8s.io/client-go/examples/out-of-cluster-client-configuration/main.go

@@ -0,0 +1,85 @@
+/*
+Copyright 2016 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.
+*/
+
+// Note: the example only works with the code within the same release/branch.
+package main
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"path/filepath"
+	"time"
+
+	"k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/tools/clientcmd"
+	// Uncomment the following line to load the gcp plugin (only required to authenticate against GKE clusters).
+	// _ "k8s.io/client-go/plugin/pkg/client/auth/gcp"
+)
+
+func main() {
+	var kubeconfig *string
+	if home := homeDir(); home != "" {
+		kubeconfig = flag.String("kubeconfig", filepath.Join(home, ".kube", "config"), "(optional) absolute path to the kubeconfig file")
+	} else {
+		kubeconfig = flag.String("kubeconfig", "", "absolute path to the kubeconfig file")
+	}
+	flag.Parse()
+
+	// use the current context in kubeconfig
+	config, err := clientcmd.BuildConfigFromFlags("", *kubeconfig)
+	if err != nil {
+		panic(err.Error())
+	}
+
+	// create the clientset
+	clientset, err := kubernetes.NewForConfig(config)
+	if err != nil {
+		panic(err.Error())
+	}
+	for {
+		pods, err := clientset.CoreV1().Pods("").List(metav1.ListOptions{})
+		if err != nil {
+			panic(err.Error())
+		}
+		fmt.Printf("There are %d pods in the cluster\n", len(pods.Items))
+
+		// Examples for error handling:
+		// - Use helper functions like e.g. errors.IsNotFound()
+		// - And/or cast to StatusError and use its properties like e.g. ErrStatus.Message
+		_, err = clientset.CoreV1().Pods("default").Get("example-xxxxx", metav1.GetOptions{})
+		if errors.IsNotFound(err) {
+			fmt.Printf("Pod not found\n")
+		} else if statusError, isStatus := err.(*errors.StatusError); isStatus {
+			fmt.Printf("Error getting pod %v\n", statusError.ErrStatus.Message)
+		} else if err != nil {
+			panic(err.Error())
+		} else {
+			fmt.Printf("Found pod\n")
+		}
+
+		time.Sleep(10 * time.Second)
+	}
+}
+
+func homeDir() string {
+	if h := os.Getenv("HOME"); h != "" {
+		return h
+	}
+	return os.Getenv("USERPROFILE") // windows
+}

vendor/k8s.io/client-go/examples/third-party-resources-deprecated/BUILD

@@ -0,0 +1,32 @@
+package(default_visibility = ["//visibility:public"])
+
+licenses(["notice"])
+
+load(
+    "@io_bazel_rules_go//go:def.bzl",
+    "go_binary",
+    "go_library",
+)
+
+go_library(
+    name = "go_default_library",
+    srcs = ["main.go"],
+    tags = ["automanaged"],
+    deps = [
+        "//vendor/k8s.io/apimachinery/pkg/api/errors:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
+        "//vendor/k8s.io/client-go/examples/third-party-resources-deprecated/apis/tpr/v1:go_default_library",
+        "//vendor/k8s.io/client-go/examples/third-party-resources-deprecated/client:go_default_library",
+        "//vendor/k8s.io/client-go/examples/third-party-resources-deprecated/controller:go_default_library",
+        "//vendor/k8s.io/client-go/kubernetes:go_default_library",
+        "//vendor/k8s.io/client-go/pkg/api/v1:go_default_library",
+        "//vendor/k8s.io/client-go/rest:go_default_library",
+        "//vendor/k8s.io/client-go/tools/clientcmd:go_default_library",
+    ],
+)
+
+go_binary(
+    name = "third-party-resources-deprecated",
+    library = ":go_default_library",
+    tags = ["automanaged"],
+)

vendor/k8s.io/client-go/examples/third-party-resources-deprecated/README.md

@@ -0,0 +1,46 @@
+# Third Party Resources Example – Deprecated
+
+**Note:** ThirdPartyResources are deprecated since 1.7. The successor is CustomResourceDefinition in the apiextensions.k8s.io API group.
+
+This particular example demonstrates how to perform basic operations such as:
+
+* How to register a new ThirdPartyResource (custom Resource type)
+* How to create/get/list instances of your new Resource type (update/delete/etc work as well but are not demonstrated) 
+* How to setup a controller on Resource handling create/update/delete events
+
+## Running
+
+```
+# assumes you have a working kubeconfig, not required if operating in-cluster
+go run *.go -kubeconfig=$HOME/.kube/config
+```
+
+## Use Cases
+
+ThirdPartyResources can be used to implement custom Resource types for your Kubernetes cluster.
+These act like most other Resources in Kubernetes, and may be `kubectl apply`'d, etc.
+
+Some example use cases:
+
+* Provisioning/Management of external datastores/databases (eg. CloudSQL/RDS instances)
+* Higher level abstractions around Kubernetes primitives (eg. a single Resource to define an etcd cluster, backed by a Service and a ReplicationController) 
+
+## Defining types
+
+Each instance of your ThirdPartyResource has an attached Spec, which should be defined via a `struct{}` to provide data format validation.
+In practice, this Spec is arbitrary key-value data that specifies the configuration/behavior of your Resource.
+
+For example, if you were implementing a ThirdPartyResource for a Database, you might provide a DatabaseSpec like the following:
+
+``` go
+type DatabaseSpec struct {
+	Databases []string `json:"databases"`
+	Users     []User   `json:"users"`
+	Version   string   `json:"version"`
+}
+
+type User struct {
+	Name     string `json:"name"`
+	Password string `json:"password"`
+}
+```

vendor/k8s.io/client-go/examples/third-party-resources-deprecated/apis/tpr/v1/BUILD

@@ -0,0 +1,37 @@
+package(default_visibility = ["//visibility:public"])
+
+licenses(["notice"])
+
+load(
+    "@io_bazel_rules_go//go:def.bzl",
+    "go_library",
+    "go_test",
+)
+
+go_test(
+    name = "go_default_test",
+    srcs = ["types_test.go"],
+    library = ":go_default_library",
+    tags = ["automanaged"],
+    deps = [
+        "//vendor/github.com/google/gofuzz:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/api/testing:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/runtime:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/runtime/serializer:go_default_library",
+    ],
+)
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "register.go",
+        "types.go",
+    ],
+    tags = ["automanaged"],
+    deps = [
+        "//vendor/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/runtime:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/runtime/schema:go_default_library",
+    ],
+)

vendor/k8s.io/client-go/examples/third-party-resources-deprecated/apis/tpr/v1/register.go

@@ -0,0 +1,49 @@
+/*
+Copyright 2017 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 v1
+
+import (
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+)
+
+var (
+	SchemeBuilder = runtime.NewSchemeBuilder(addKnownTypes)
+	AddToScheme   = SchemeBuilder.AddToScheme
+)
+
+// GroupName is the group name use in this package.
+const GroupName = "tpr.client-go.k8s.io"
+
+// SchemeGroupVersion is the group version used to register these objects.
+var SchemeGroupVersion = schema.GroupVersion{Group: GroupName, Version: "v1"}
+
+// Resource takes an unqualified resource and returns a Group-qualified GroupResource.
+func Resource(resource string) schema.GroupResource {
+	return SchemeGroupVersion.WithResource(resource).GroupResource()
+}
+
+// addKnownTypes adds the set of types defined in this package to the supplied scheme.
+func addKnownTypes(scheme *runtime.Scheme) error {
+	scheme.AddKnownTypes(SchemeGroupVersion,
+		&Example{},
+		&ExampleList{},
+	)
+	metav1.AddToGroupVersion(scheme, SchemeGroupVersion)
+	return nil
+}

vendor/k8s.io/client-go/examples/third-party-resources-deprecated/apis/tpr/v1/types.go

@@ -0,0 +1,53 @@
+/*
+Copyright 2017 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 v1
+
+import (
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+const ExampleResourcePlural = "examples"
+
+type Example struct {
+	metav1.TypeMeta   `json:",inline"`
+	metav1.ObjectMeta `json:"metadata"`
+	Spec              ExampleSpec   `json:"spec"`
+	Status            ExampleStatus `json:"status,omitempty"`
+}
+
+type ExampleSpec struct {
+	Foo string `json:"foo"`
+	Bar bool   `json:"bar"`
+}
+
+type ExampleStatus struct {
+	State   ExampleState `json:"state,omitempty"`
+	Message string       `json:"message,omitempty"`
+}
+
+type ExampleState string
+
+const (
+	ExampleStateCreated   ExampleState = "Created"
+	ExampleStateProcessed ExampleState = "Processed"
+)
+
+type ExampleList struct {
+	metav1.TypeMeta `json:",inline"`
+	metav1.ListMeta `json:"metadata"`
+	Items           []Example `json:"items"`
+}

vendor/k8s.io/client-go/examples/third-party-resources-deprecated/apis/tpr/v1/types_test.go

@@ -0,0 +1,63 @@
+/*
+Copyright 2017 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 v1
+
+import (
+	"math/rand"
+	"testing"
+
+	"github.com/google/gofuzz"
+
+	apitesting "k8s.io/apimachinery/pkg/api/testing"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/serializer"
+)
+
+var _ runtime.Object = &Example{}
+var _ metav1.ObjectMetaAccessor = &Example{}
+
+var _ runtime.Object = &ExampleList{}
+var _ metav1.ListMetaAccessor = &ExampleList{}
+
+func exampleFuzzerFuncs(t apitesting.TestingCommon) []interface{} {
+	return []interface{}{
+		func(obj *ExampleList, c fuzz.Continue) {
+			c.FuzzNoCustom(obj)
+			obj.Items = make([]Example, c.Intn(10))
+			for i := range obj.Items {
+				c.Fuzz(&obj.Items[i])
+			}
+		},
+	}
+}
+
+// TestRoundTrip tests that the third-party kinds can be marshaled and unmarshaled correctly to/from JSON
+// without the loss of information. Moreover, deep copy is tested.
+func TestRoundTrip(t *testing.T) {
+	scheme := runtime.NewScheme()
+	codecs := serializer.NewCodecFactory(scheme)
+
+	AddToScheme(scheme)
+
+	seed := rand.Int63()
+	fuzzerFuncs := apitesting.MergeFuzzerFuncs(t, apitesting.GenericFuzzerFuncs(t, codecs), exampleFuzzerFuncs(t))
+	fuzzer := apitesting.FuzzerFor(fuzzerFuncs, rand.NewSource(seed))
+
+	apitesting.RoundTripSpecificKindWithoutProtobuf(t, SchemeGroupVersion.WithKind("Example"), scheme, codecs, fuzzer, nil)
+	apitesting.RoundTripSpecificKindWithoutProtobuf(t, SchemeGroupVersion.WithKind("ExampleList"), scheme, codecs, fuzzer, nil)
+}

vendor/k8s.io/client-go/examples/third-party-resources-deprecated/client/BUILD

@@ -0,0 +1,29 @@
+package(default_visibility = ["//visibility:public"])
+
+licenses(["notice"])
+
+load(
+    "@io_bazel_rules_go//go:def.bzl",
+    "go_library",
+)
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "client.go",
+        "tpr.go",
+    ],
+    tags = ["automanaged"],
+    deps = [
+        "//vendor/k8s.io/apimachinery/pkg/api/errors:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/runtime:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/runtime/serializer:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/util/wait:go_default_library",
+        "//vendor/k8s.io/client-go/examples/third-party-resources-deprecated/apis/tpr/v1:go_default_library",
+        "//vendor/k8s.io/client-go/kubernetes:go_default_library",
+        "//vendor/k8s.io/client-go/pkg/api/v1:go_default_library",
+        "//vendor/k8s.io/client-go/pkg/apis/extensions/v1beta1:go_default_library",
+        "//vendor/k8s.io/client-go/rest:go_default_library",
+    ],
+)

vendor/k8s.io/client-go/examples/third-party-resources-deprecated/client/client.go

@@ -0,0 +1,45 @@
+/*
+Copyright 2017 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 client
+
+import (
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/serializer"
+	"k8s.io/client-go/rest"
+
+	tprv1 "k8s.io/client-go/examples/third-party-resources-deprecated/apis/tpr/v1"
+)
+
+func NewClient(cfg *rest.Config) (*rest.RESTClient, *runtime.Scheme, error) {
+	scheme := runtime.NewScheme()
+	if err := tprv1.AddToScheme(scheme); err != nil {
+		return nil, nil, err
+	}
+
+	config := *cfg
+	config.GroupVersion = &tprv1.SchemeGroupVersion
+	config.APIPath = "/apis"
+	config.ContentType = runtime.ContentTypeJSON
+	config.NegotiatedSerializer = serializer.DirectCodecFactory{CodecFactory: serializer.NewCodecFactory(scheme)}
+
+	client, err := rest.RESTClientFor(&config)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	return client, scheme, nil
+}

vendor/k8s.io/client-go/examples/third-party-resources-deprecated/client/tpr.go

@@ -0,0 +1,76 @@
+/*
+Copyright 2017 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 client
+
+import (
+	"time"
+
+	apierrors "k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/util/wait"
+	tprv1 "k8s.io/client-go/examples/third-party-resources-deprecated/apis/tpr/v1"
+	"k8s.io/client-go/kubernetes"
+	apiv1 "k8s.io/client-go/pkg/api/v1"
+	"k8s.io/client-go/pkg/apis/extensions/v1beta1"
+	"k8s.io/client-go/rest"
+	// Uncomment the following line to load the gcp plugin (only required to authenticate against GKE clusters).
+	// _ "k8s.io/client-go/plugin/pkg/client/auth/gcp"
+)
+
+func CreateTPR(clientset kubernetes.Interface) error {
+	tpr := &v1beta1.ThirdPartyResource{
+		ObjectMeta: metav1.ObjectMeta{
+			Name: "example." + tprv1.GroupName,
+		},
+		Versions: []v1beta1.APIVersion{
+			{Name: tprv1.SchemeGroupVersion.Version},
+		},
+		Description: "An Example ThirdPartyResource",
+	}
+	_, err := clientset.ExtensionsV1beta1().ThirdPartyResources().Create(tpr)
+	return err
+}
+
+func WaitForExampleResource(exampleClient *rest.RESTClient) error {
+	return wait.Poll(100*time.Millisecond, 60*time.Second, func() (bool, error) {
+		_, err := exampleClient.Get().Namespace(apiv1.NamespaceDefault).Resource(tprv1.ExampleResourcePlural).DoRaw()
+		if err == nil {
+			return true, nil
+		}
+		if apierrors.IsNotFound(err) {
+			return false, nil
+		}
+		return false, err
+	})
+}
+
+func WaitForExampleInstanceProcessed(exampleClient *rest.RESTClient, name string) error {
+	return wait.Poll(100*time.Millisecond, 10*time.Second, func() (bool, error) {
+		var example tprv1.Example
+		err := exampleClient.Get().
+			Resource(tprv1.ExampleResourcePlural).
+			Namespace(apiv1.NamespaceDefault).
+			Name(name).
+			Do().Into(&example)
+
+		if err == nil && example.Status.State == tprv1.ExampleStateProcessed {
+			return true, nil
+		}
+
+		return false, err
+	})
+}

vendor/k8s.io/client-go/examples/third-party-resources-deprecated/controller/BUILD

@@ -0,0 +1,22 @@
+package(default_visibility = ["//visibility:public"])
+
+licenses(["notice"])
+
+load(
+    "@io_bazel_rules_go//go:def.bzl",
+    "go_library",
+)
+
+go_library(
+    name = "go_default_library",
+    srcs = ["controller.go"],
+    tags = ["automanaged"],
+    deps = [
+        "//vendor/k8s.io/apimachinery/pkg/fields:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/runtime:go_default_library",
+        "//vendor/k8s.io/client-go/examples/third-party-resources-deprecated/apis/tpr/v1:go_default_library",
+        "//vendor/k8s.io/client-go/pkg/api/v1:go_default_library",
+        "//vendor/k8s.io/client-go/rest:go_default_library",
+        "//vendor/k8s.io/client-go/tools/cache:go_default_library",
+    ],
+)

vendor/k8s.io/client-go/examples/third-party-resources-deprecated/controller/controller.go

@@ -0,0 +1,126 @@
+/*
+Copyright 2017 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 controller
+
+import (
+	"context"
+	"fmt"
+
+	"k8s.io/apimachinery/pkg/fields"
+	"k8s.io/apimachinery/pkg/runtime"
+	apiv1 "k8s.io/client-go/pkg/api/v1"
+	"k8s.io/client-go/rest"
+	"k8s.io/client-go/tools/cache"
+
+	tprv1 "k8s.io/client-go/examples/third-party-resources-deprecated/apis/tpr/v1"
+)
+
+// Watcher is an example of watching on resource create/update/delete events
+type ExampleController struct {
+	ExampleClient *rest.RESTClient
+	ExampleScheme *runtime.Scheme
+}
+
+// Run starts an Example resource controller
+func (c *ExampleController) Run(ctx context.Context) error {
+	fmt.Print("Watch Example objects\n")
+
+	// Watch Example objects
+	_, err := c.watchExamples(ctx)
+	if err != nil {
+		fmt.Printf("Failed to register watch for Example resource: %v\n", err)
+		return err
+	}
+
+	<-ctx.Done()
+	return ctx.Err()
+}
+
+func (c *ExampleController) watchExamples(ctx context.Context) (cache.Controller, error) {
+	source := cache.NewListWatchFromClient(
+		c.ExampleClient,
+		tprv1.ExampleResourcePlural,
+		apiv1.NamespaceAll,
+		fields.Everything())
+
+	_, controller := cache.NewInformer(
+		source,
+
+		// The object type.
+		&tprv1.Example{},
+
+		// resyncPeriod
+		// Every resyncPeriod, all resources in the cache will retrigger events.
+		// Set to 0 to disable the resync.
+		0,
+
+		// Your custom resource event handlers.
+		cache.ResourceEventHandlerFuncs{
+			AddFunc:    c.onAdd,
+			UpdateFunc: c.onUpdate,
+			DeleteFunc: c.onDelete,
+		})
+
+	go controller.Run(ctx.Done())
+	return controller, nil
+}
+
+func (c *ExampleController) onAdd(obj interface{}) {
+	example := obj.(*tprv1.Example)
+	fmt.Printf("[CONTROLLER] OnAdd %s\n", example.ObjectMeta.SelfLink)
+
+	// NEVER modify objects from the store. It's a read-only, local cache.
+	// You can use exampleScheme.Copy() to make a deep copy of original object and modify this copy
+	// Or create a copy manually for better performance
+	copyObj, err := c.ExampleScheme.Copy(example)
+	if err != nil {
+		fmt.Printf("ERROR creating a deep copy of example object: %v\n", err)
+		return
+	}
+
+	exampleCopy := copyObj.(*tprv1.Example)
+	exampleCopy.Status = tprv1.ExampleStatus{
+		State:   tprv1.ExampleStateProcessed,
+		Message: "Successfully processed by controller",
+	}
+
+	err = c.ExampleClient.Put().
+		Name(example.ObjectMeta.Name).
+		Namespace(example.ObjectMeta.Namespace).
+		Resource(tprv1.ExampleResourcePlural).
+		Body(exampleCopy).
+		Do().
+		Error()
+
+	if err != nil {
+		fmt.Printf("ERROR updating status: %v\n", err)
+	} else {
+		fmt.Printf("UPDATED status: %#v\n", exampleCopy)
+	}
+}
+
+func (c *ExampleController) onUpdate(oldObj, newObj interface{}) {
+	oldExample := oldObj.(*tprv1.Example)
+	newExample := newObj.(*tprv1.Example)
+	fmt.Printf("[CONTROLLER] OnUpdate oldObj: %s\n", oldExample.ObjectMeta.SelfLink)
+	fmt.Printf("[CONTROLLER] OnUpdate newObj: %s\n", newExample.ObjectMeta.SelfLink)
+}
+
+func (c *ExampleController) onDelete(obj interface{}) {
+	example := obj.(*tprv1.Example)
+	fmt.Printf("[CONTROLLER] OnDelete %s\n", example.ObjectMeta.SelfLink)
+}

vendor/k8s.io/client-go/examples/third-party-resources-deprecated/main.go

@@ -0,0 +1,132 @@
+/*
+Copyright 2017 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.
+*/
+
+// Note: the example only works with the code within the same release/branch.
+package main
+
+import (
+	"context"
+	"flag"
+	"fmt"
+
+	apierrors "k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/client-go/kubernetes"
+	apiv1 "k8s.io/client-go/pkg/api/v1"
+	"k8s.io/client-go/rest"
+	"k8s.io/client-go/tools/clientcmd"
+
+	// Uncomment the following line to load the gcp plugin (only required to authenticate against GKE clusters).
+	// _ "k8s.io/client-go/plugin/pkg/client/auth/gcp"
+
+	tprv1 "k8s.io/client-go/examples/third-party-resources-deprecated/apis/tpr/v1"
+	exampleclient "k8s.io/client-go/examples/third-party-resources-deprecated/client"
+	examplecontroller "k8s.io/client-go/examples/third-party-resources-deprecated/controller"
+)
+
+func main() {
+	kubeconfig := flag.String("kubeconfig", "", "Path to a kube config. Only required if out-of-cluster.")
+	flag.Parse()
+
+	// Create the client config. Use kubeconfig if given, otherwise assume in-cluster.
+	config, err := buildConfig(*kubeconfig)
+	if err != nil {
+		panic(err)
+	}
+
+	clientset, err := kubernetes.NewForConfig(config)
+	if err != nil {
+		panic(err)
+	}
+
+	// initialize third party resource if it does not exist
+	err = exampleclient.CreateTPR(clientset)
+	if err != nil && !apierrors.IsAlreadyExists(err) {
+		panic(err)
+	}
+
+	// make a new config for our extension's API group, using the first config as a baseline
+	exampleClient, exampleScheme, err := exampleclient.NewClient(config)
+	if err != nil {
+		panic(err)
+	}
+
+	// wait until TPR gets processed
+	err = exampleclient.WaitForExampleResource(exampleClient)
+	if err != nil {
+		panic(err)
+	}
+
+	// start a controller on instances of our TPR
+	controller := examplecontroller.ExampleController{
+		ExampleClient: exampleClient,
+		ExampleScheme: exampleScheme,
+	}
+
+	ctx, cancelFunc := context.WithCancel(context.Background())
+	defer cancelFunc()
+	go controller.Run(ctx)
+
+	// Create an instance of our TPR
+	example := &tprv1.Example{
+		ObjectMeta: metav1.ObjectMeta{
+			Name: "example1",
+		},
+		Spec: tprv1.ExampleSpec{
+			Foo: "hello",
+			Bar: true,
+		},
+		Status: tprv1.ExampleStatus{
+			State:   tprv1.ExampleStateCreated,
+			Message: "Created, not processed yet",
+		},
+	}
+	var result tprv1.Example
+	err = exampleClient.Post().
+		Resource(tprv1.ExampleResourcePlural).
+		Namespace(apiv1.NamespaceDefault).
+		Body(example).
+		Do().Into(&result)
+	if err == nil {
+		fmt.Printf("CREATED: %#v\n", result)
+	} else if apierrors.IsAlreadyExists(err) {
+		fmt.Printf("ALREADY EXISTS: %#v\n", result)
+	} else {
+		panic(err)
+	}
+
+	// Poll until Example object is handled by controller and gets status updated to "Processed"
+	err = exampleclient.WaitForExampleInstanceProcessed(exampleClient, "example1")
+	if err != nil {
+		panic(err)
+	}
+	fmt.Print("PROCESSED\n")
+
+	// Fetch a list of our TPRs
+	exampleList := tprv1.ExampleList{}
+	err = exampleClient.Get().Resource(tprv1.ExampleResourcePlural).Do().Into(&exampleList)
+	if err != nil {
+		panic(err)
+	}
+	fmt.Printf("LIST: %#v\n", exampleList)
+}
+
+func buildConfig(kubeconfig string) (*rest.Config, error) {
+	if kubeconfig != "" {
+		return clientcmd.BuildConfigFromFlags("", kubeconfig)
+	}
+	return rest.InClusterConfig()
+}

vendor/k8s.io/client-go/examples/workqueue/BUILD

@@ -0,0 +1,33 @@
+package(default_visibility = ["//visibility:public"])
+
+licenses(["notice"])
+
+load(
+    "@io_bazel_rules_go//go:def.bzl",
+    "go_binary",
+    "go_library",
+)
+
+go_binary(
+    name = "workqueue",
+    library = ":go_default_library",
+    tags = ["automanaged"],
+)
+
+go_library(
+    name = "go_default_library",
+    srcs = ["main.go"],
+    tags = ["automanaged"],
+    deps = [
+        "//vendor/github.com/golang/glog:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/fields:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/util/runtime:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/util/wait:go_default_library",
+        "//vendor/k8s.io/client-go/kubernetes:go_default_library",
+        "//vendor/k8s.io/client-go/pkg/api/v1:go_default_library",
+        "//vendor/k8s.io/client-go/tools/cache:go_default_library",
+        "//vendor/k8s.io/client-go/tools/clientcmd:go_default_library",
+        "//vendor/k8s.io/client-go/util/workqueue:go_default_library",
+    ],
+)

vendor/k8s.io/client-go/examples/workqueue/README.md

@@ -0,0 +1,17 @@
+# Workqueue Example
+
+This example demonstrates how to write a controller which follows the states
+of watched resources.
+
+It demonstrates how to:
+ * combine the workqueue with a cache to a full controller
+ * synchronize the controller on startup
+
+The example is based on https://git.k8s.io/community/contributors/devel/controllers.md.
+
+## Running
+
+```
+# if outside of the cluster
+go run *.go -kubeconfig=/my/config -logtostderr=true
+```

vendor/k8s.io/client-go/examples/workqueue/main.go

@@ -0,0 +1,217 @@
+/*
+Copyright 2017 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 main
+
+import (
+	"flag"
+	"fmt"
+	"time"
+
+	"github.com/golang/glog"
+
+	meta_v1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/fields"
+	"k8s.io/apimachinery/pkg/util/runtime"
+	"k8s.io/apimachinery/pkg/util/wait"
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/pkg/api/v1"
+	"k8s.io/client-go/tools/cache"
+	"k8s.io/client-go/tools/clientcmd"
+	"k8s.io/client-go/util/workqueue"
+)
+
+type Controller struct {
+	indexer  cache.Indexer
+	queue    workqueue.RateLimitingInterface
+	informer cache.Controller
+}
+
+func NewController(queue workqueue.RateLimitingInterface, indexer cache.Indexer, informer cache.Controller) *Controller {
+	return &Controller{
+		informer: informer,
+		indexer:  indexer,
+		queue:    queue,
+	}
+}
+
+func (c *Controller) processNextItem() bool {
+	// Wait until there is a new item in the working queue
+	key, quit := c.queue.Get()
+	if quit {
+		return false
+	}
+	// Tell the queue that we are done with processing this key. This unblocks the key for other workers
+	// This allows safe parallel processing because two pods with the same key are never processed in
+	// parallel.
+	defer c.queue.Done(key)
+
+	// Invoke the method containing the business logic
+	err := c.syncToStdout(key.(string))
+	// Handle the error if something went wrong during the execution of the business logic
+	c.handleErr(err, key)
+	return true
+}
+
+// syncToStdout is the business logic of the controller. In this controller it simply prints
+// information about the pod to stdout. In case an error happened, it has to simply return the error.
+// The retry logic should not be part of the business logic.
+func (c *Controller) syncToStdout(key string) error {
+	obj, exists, err := c.indexer.GetByKey(key)
+	if err != nil {
+		glog.Errorf("Fetching object with key %s from store failed with %v", key, err)
+		return err
+	}
+
+	if !exists {
+		// Below we will warm up our cache with a Pod, so that we will see a delete for one pod
+		fmt.Printf("Pod %s does not exist anymore\n", key)
+	} else {
+		// Note that you also have to check the uid if you have a local controlled resource, which
+		// is dependent on the actual instance, to detect that a Pod was recreated with the same name
+		fmt.Printf("Sync/Add/Update for Pod %s\n", obj.(*v1.Pod).GetName())
+	}
+	return nil
+}
+
+// handleErr checks if an error happened and makes sure we will retry later.
+func (c *Controller) handleErr(err error, key interface{}) {
+	if err == nil {
+		// Forget about the #AddRateLimited history of the key on every successful synchronization.
+		// This ensures that future processing of updates for this key is not delayed because of
+		// an outdated error history.
+		c.queue.Forget(key)
+		return
+	}
+
+	// This controller retries 5 times if something goes wrong. After that, it stops trying.
+	if c.queue.NumRequeues(key) < 5 {
+		glog.Infof("Error syncing pod %v: %v", key, err)
+
+		// Re-enqueue the key rate limited. Based on the rate limiter on the
+		// queue and the re-enqueue history, the key will be processed later again.
+		c.queue.AddRateLimited(key)
+		return
+	}
+
+	c.queue.Forget(key)
+	// Report to an external entity that, even after several retries, we could not successfully process this key
+	runtime.HandleError(err)
+	glog.Infof("Dropping pod %q out of the queue: %v", key, err)
+}
+
+func (c *Controller) Run(threadiness int, stopCh chan struct{}) {
+	defer runtime.HandleCrash()
+
+	// Let the workers stop when we are done
+	defer c.queue.ShutDown()
+	glog.Info("Starting Pod controller")
+
+	go c.informer.Run(stopCh)
+
+	// Wait for all involved caches to be synced, before processing items from the queue is started
+	if !cache.WaitForCacheSync(stopCh, c.informer.HasSynced) {
+		runtime.HandleError(fmt.Errorf("Timed out waiting for caches to sync"))
+		return
+	}
+
+	for i := 0; i < threadiness; i++ {
+		go wait.Until(c.runWorker, time.Second, stopCh)
+	}
+
+	<-stopCh
+	glog.Info("Stopping Pod controller")
+}
+
+func (c *Controller) runWorker() {
+	for c.processNextItem() {
+	}
+}
+
+func main() {
+	var kubeconfig string
+	var master string
+
+	flag.StringVar(&kubeconfig, "kubeconfig", "", "absolute path to the kubeconfig file")
+	flag.StringVar(&master, "master", "", "master url")
+	flag.Parse()
+
+	// creates the connection
+	config, err := clientcmd.BuildConfigFromFlags(master, kubeconfig)
+	if err != nil {
+		glog.Fatal(err)
+	}
+
+	// creates the clientset
+	clientset, err := kubernetes.NewForConfig(config)
+	if err != nil {
+		glog.Fatal(err)
+	}
+
+	// create the pod watcher
+	podListWatcher := cache.NewListWatchFromClient(clientset.Core().RESTClient(), "pods", v1.NamespaceDefault, fields.Everything())
+
+	// create the workqueue
+	queue := workqueue.NewRateLimitingQueue(workqueue.DefaultControllerRateLimiter())
+
+	// Bind the workqueue to a cache with the help of an informer. This way we make sure that
+	// whenever the cache is updated, the pod key is added to the workqueue.
+	// Note that when we finally process the item from the workqueue, we might see a newer version
+	// of the Pod than the version which was responsible for triggering the update.
+	indexer, informer := cache.NewIndexerInformer(podListWatcher, &v1.Pod{}, 0, cache.ResourceEventHandlerFuncs{
+		AddFunc: func(obj interface{}) {
+			key, err := cache.MetaNamespaceKeyFunc(obj)
+			if err == nil {
+				queue.Add(key)
+			}
+		},
+		UpdateFunc: func(old interface{}, new interface{}) {
+			key, err := cache.MetaNamespaceKeyFunc(new)
+			if err == nil {
+				queue.Add(key)
+			}
+		},
+		DeleteFunc: func(obj interface{}) {
+			// IndexerInformer uses a delta queue, therefore for deletes we have to use this
+			// key function.
+			key, err := cache.DeletionHandlingMetaNamespaceKeyFunc(obj)
+			if err == nil {
+				queue.Add(key)
+			}
+		},
+	}, cache.Indexers{})
+
+	controller := NewController(queue, indexer, informer)
+
+	// We can now warm up the cache for initial synchronization.
+	// Let's suppose that we knew about a pod "mypod" on our last run, therefore add it to the cache.
+	// If this pod is not there anymore, the controller will be notified about the removal after the
+	// cache has synchronized.
+	indexer.Add(&v1.Pod{
+		ObjectMeta: meta_v1.ObjectMeta{
+			Name:      "mypod",
+			Namespace: v1.NamespaceDefault,
+		},
+	})
+
+	// Now let's start the controller
+	stop := make(chan struct{})
+	defer close(stop)
+	go controller.Run(1, stop)
+
+	// Wait forever
+	select {}
+}