Merge pull request #1299 from Gurpartap/guestbook-go

Rewrite of the Guestbook example in Go

examples/guestbook-go/README.md

@@ -0,0 +1,174 @@
+## GuestBook example
+
+This example shows how to build a simple multi-tier web application using Kubernetes and Docker.
+
+The example combines a web frontend, a redis master for storage and a replicated set of redis slaves.
+
+### Step Zero: Prerequisites
+
+This example assumes that you have forked the repository and [turned up a Kubernetes cluster](https://github.com/GoogleCloudPlatform/kubernetes#contents):
+
+```shell
+$ cd kubernetes
+$ hack/dev-build-and-up.sh
+```
+
+### Step One: Turn up the redis master.
+
+Use the file `examples/guestbook-go/redis-master-pod.json` which describes a single pod running a redis key-value server in a container.
+
+Create the redis pod in your Kubernetes cluster using the `kubecfg` CLI:
+
+```shell
+$ cluster/kubecfg.sh -c examples/guestbook-go/redis-master-pod.json create pods
+```
+
+Once that's up you can list the pods in the cluster, to verify that the master is running:
+
+```shell
+$ cluster/kubecfg.sh list pods
+```
+
+You'll see a single redis master pod. It will also display the machine that the pod is running on once it gets placed (may take up to thirty seconds).
+
+```
+  ID                Image(s)            Host                                          Labels                 Status
+----------          ----------          ----------                                    ----------             ----------
+redis-master-pod    gurpartap/redis     kubernetes-minion-3.c.briandpe-api.internal   name=redis,role=master      Running
+```
+
+If you ssh to that machine, you can run `docker ps` to see the actual pod:
+
+```shell
+$ gcutil ssh --zone us-central1-b kubernetes-minion-3
+$ sudo docker ps
+
+me@kubernetes-minion-3:~$ sudo docker ps
+CONTAINER ID  IMAGE                   COMMAND              CREATED         STATUS
+e443647cd064  gurpartap/redis:latest  redis-server /etc/r  22 minutes ago  Up 22 minutes
+```
+
+(Note that initial `docker pull` may take a few minutes, depending on network conditions.)
+
+### Step Two: Turn up the master service.
+A Kubernetes 'service' is a named load balancer that proxies traffic to one or more containers. The services in a Kubernetes cluster are discoverable inside other containers via environment variables. Services find the containers to load balance based on pod labels.
+
+The pod that you created in Step One has the label `name=redis` and `role=master`. The selector field of the service determines which pods will receive the traffic sent to the service.  Use the file `examples/guestbook-go/redis-master-service.json`
+
+To create the service with the `kubecfg` cli:
+
+```shell
+$ cluster/kubecfg.sh -c examples/guestbook-go/redis-master-service.json create services
+ID                     Labels              Selector                 Port
+----------             ----------          ----------               ----------
+redis-master                               name=redis,role=master   6379
+```
+
+This will cause all pods to see the redis master apparently running on localhost:6379.
+
+Once created, the service proxy on each minion is configured to set up a proxy on the specified port (in this case port 6379).
+
+### Step Three: Turn up the replicated slave pods.
+Although the redis master is a single pod, the redis read slaves are a 'replicated' pod. In Kubernetes, a replication controller is responsible for managing multiple instances of a replicated pod.
+
+Use the file `examples/guestbook-go/redis-slave-controller.json`
+
+to create the replication controller by running:
+
+```shell
+$ cluster/kubecfg.sh -c examples/guestbook-go/redis-slave-controller.json create replicationControllers
+  ID                    Image(s)         Selector               Replicas
+----------              ----------       ----------             ----------
+redis-slave-controller  gurpartap/redis  name=redis,role=slave  2
+```
+
+The redis slave configures itself by looking for the Kubernetes service environment variables in the container environment. In particular, the redis slave is started with the following command:
+
+```shell
+redis-server --slaveof $SERVICE_HOST $REDIS_MASTER_SERVICE_PORT
+```
+
+Once that's up you can list the pods in the cluster, to verify that the master and slaves are running:
+
+```shell
+$ cluster/kubecfg.sh list pods
+  ID              Image(s)         Host                                         Labels                                                         Status
+----------        ----------       ----------                                   ----------                                                     ----------
+redis-master-pod  gurpartap/redis  kubernetes-minion-3.c.briandpe-api.internal  name=redis,role=master                                              Running
+4d65822107fcfd52  gurpartap/redis  kubernetes-minion-3.c.briandpe-api.internal  name=redis,role=slave,replicationController=redis-slave-controller  Running
+78629a0f5f3f164f  gurpartap/redis  kubernetes-minion-4.c.briandpe-api.internal  name=redis,role=slave,replicationController=redis-slave-controller  Running
+```
+
+You will see a single redis master pod and two redis slave pods.
+
+### Step Four: Create the redis slave service.
+
+Just like the master, we want to have a service to proxy connections to the read slaves. In this case, in addition to discovery, the slave service provides transparent load balancing to clients. The service specification for the slaves is in `examples/guestbook-go/redis-slave-service.json`
+
+This time the selector for the service is `name=redis,role=slave`, because that identifies the pods running redis slaves. It may also be helpful to set labels on your service itself--as we've done here--to make it easy to locate them with the `kubecfg -l "label=value" list services` command.
+
+Now that you have created the service specification, create it in your cluster with the `kubecfg` CLI:
+
+```shell
+$ cluster/kubecfg.sh -c examples/guestbook-go/redis-slave-service.json create services
+  ID         Labels            Selector               Port
+----------   ----------        ----------             ----------
+redis-slave  name=redis-slave  name=redis,role=slave  6379
+```
+
+### Step Five: Create the guestbook pod.
+
+This is a simple Go net/http ([negroni](https://github.com/codegangsta/negroni) based) server that is configured to talk to either the slave or master services depending on whether the request is a read or a write. It exposes a simple JSON interface, and serves a jQuery-Ajax based UX. Like the redis read slaves it is a replicated service instantiated by a replication controller.
+
+The pod is described in the file `examples/guestbook-go/guestbook-controller.json`:
+
+Using this file, you can turn up your guestbook with:
+
+```shell
+$ cluster/kubecfg.sh -c examples/guestbook-go/guestbook-controller.json create replicationControllers
+  ID                  Image(s)         Selector       Replicas
+----------            ----------       ----------     ----------
+guestbook-controller  gurpartap/redis  name=guestbook  3
+```
+
+Once that's up (it may take ten to thirty seconds to create the pods) you can list the pods in the cluster, to verify that the master, slaves and guestbook frontends are running:
+
+```shell
+$ cluster/kubecfg.sh list pods
+  ID              Image(s)              Host                                         Labels                                                              Status
+----------        ----------            ----------                                   ----------                                                          ----------
+redis-master-pod  gurpartap/redis       kubernetes-minion-3.c.briandpe-api.internal  name=redis,role=master                                              Running
+4d65822107fcfd52  gurpartap/redis       kubernetes-minion-3.c.briandpe-api.internal  name=redis,role=slave,replicationController=redis-slave-controller  Running
+380704bb7b4d7c03  kubernetes/guestbook  kubernetes-minion-3.c.briandpe-api.internal  name=guestbook,replicationController=guestbook-controller           Running
+55104dc76695721d  kubernetes/guestbook  kubernetes-minion-2.c.briandpe-api.internal  name=guestbook,replicationController=guestbook-controller           Running
+365a858149c6e2d1  kubernetes/guestbook  kubernetes-minion-1.c.briandpe-api.internal  name=guestbook,replicationController=guestbook-controller           Running
+78629a0f5f3f164f  gurpartap/redis       kubernetes-minion-4.c.briandpe-api.internal  name=redis,role=slave,replicationController=redis-slave-controller  Running
+```
+
+You will see a single redis master pod, two redis slaves, and three guestbook pods.
+
+To play with the service itself, find the name of a guestbook, grab the external IP of that host from the [Google Cloud Console][cloud-console] or the `gcutil` tool, and visit `http://<host-ip>:3000`.
+
+```shell
+$ gcutil listinstances
+```
+
+You may need to open the firewall for port 3000 using the [console][cloud-console] or the `gcutil` tool. The following command will allow traffic from any source to instances tagged `kubernetes-minion`:
+
+```shell
+$ gcutil addfirewall --allowed=tcp:3000 --target_tags=kubernetes-minion kubernetes-minion-3000
+```
+
+If you are running Kubernetes locally, you can just visit http://localhost:3000
+For details about limiting traffic to specific sources, see the [gcutil documentation][gcutil-docs]
+
+[cloud-console]: https://console.developer.google.com
+[gcutil-docs]: https://developers.google.com/compute/docs/gcutil/reference/firewall#addfirewall
+
+### Step Six: Cleanup
+
+To turn down a Kubernetes cluster:
+
+```shell
+$ cluster/kube-down.sh
+```

examples/guestbook-go/_src/Dockerfile

@@ -0,0 +1,9 @@
+FROM google/golang:latest
+
+RUN mkdir -p /gopath/src/github.com/GoogleCloudPlatform/ && cd /gopath/src/github.com/GoogleCloudPlatform/ && \
+    git clone http://github.com/GoogleCloudPlatform/kubernetes && \
+    cd /gopath/src/github.com/GoogleCloudPlatform/kubernetes/examples/guestbook-go/src/ && \
+    go get && go build -o ../bin/guestbook && \
+    cp ./guestbook/Dockerfile /gopath/src/github.com/GoogleCloudPlatform/kubernetes/examples/guestbook-go/
+
+CMD docker build --rm --force-rm -t kubernetes/guestbook /gopath/src/github.com/GoogleCloudPlatform/kubernetes/examples/guestbook-go/

examples/guestbook-go/_src/README.md

@@ -0,0 +1,42 @@
+## Building and releasing Guestbook Image
+
+Guestbook build process employs the usage of docker-in-docker to build an image within another. This requires that the build image has access to the `docker` program's binary, which defaults to the docker available on your host machine. In the case of boot2docker, `DOCKER_BIN` must be set to the binary's location in the boot2docker's vm.
+
+Releasing the image requires that you have access to the docker registry user account which will host the image.
+
+To build and release the guestbook image:
+
+    cd examples/guestbook-go/src
+    ./script/release.sh
+
+If you're using boot2docker, specify the `DOCKER_BIN` environment variable
+
+    DOCKER_BIN="$(boot2docker ssh which docker)" ./script/release.sh
+
+#### Step by step
+
+If you may want to, you can build and push the image step by step.
+
+###### Start fresh before building
+
+    ./script/clean.sh 2> /dev/null
+
+###### Build
+
+Builds a docker image that builds the app and packages it into a minimal docker image
+
+    ./script/build.sh
+
+If you're using boot2docker, specify the `DOCKER_BIN` environment variable
+
+    DOCKER_BIN="$(boot2docker ssh which docker)" ./script/build.sh
+
+###### Push
+
+Accepts an optional tag (defaults to "latest")
+
+    ./script/push.sh [TAG]
+
+###### Clean up
+
+    ./script/clean.sh

examples/guestbook-go/_src/guestbook/Dockerfile

@@ -0,0 +1,10 @@
+FROM busybox:ubuntu-14.04
+
+ADD ./bin/guestbook /app/guestbook
+ADD ./src/public/index.html /app/public/index.html
+ADD ./src/public/script.js /app/public/script.js
+ADD ./src/public/style.css /app/public/style.css
+
+WORKDIR /app
+CMD ["./guestbook"]
+EXPOSE 3000

examples/guestbook-go/_src/main.go

@@ -0,0 +1,86 @@
+/*
+Copyright 2014 Google Inc. All rights reserved.
+
+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 (
+	"encoding/json"
+	"net/http"
+	"os"
+	"strings"
+
+	"github.com/codegangsta/negroni"
+	"github.com/gorilla/mux"
+	"github.com/xyproto/simpleredis"
+)
+
+var pool *simpleredis.ConnectionPool
+
+func ListRangeHandler(rw http.ResponseWriter, req *http.Request) {
+	key := mux.Vars(req)["key"]
+	list := simpleredis.NewList(pool, key)
+	members := HandleError(list.GetAll()).([]string)
+	membersJSON := HandleError(json.MarshalIndent(members, "", "  ")).([]byte)
+	rw.Write(membersJSON)
+}
+
+func ListPushHandler(rw http.ResponseWriter, req *http.Request) {
+	key := mux.Vars(req)["key"]
+	value := mux.Vars(req)["value"]
+	list := simpleredis.NewList(pool, key)
+	HandleError(nil, list.Add(value))
+	ListRangeHandler(rw, req)
+}
+
+func InfoHandler(rw http.ResponseWriter, req *http.Request) {
+	info := HandleError(pool.Get(0).Do("INFO")).([]byte)
+	rw.Write(info)
+}
+
+func EnvHandler(rw http.ResponseWriter, req *http.Request) {
+	environment := make(map[string]string)
+	for _, item := range os.Environ() {
+		splits := strings.Split(item, "=")
+		key := splits[0]
+		val := strings.Join(splits[1:], "=")
+		environment[key] = val
+	}
+
+	envJSON := HandleError(json.MarshalIndent(environment, "", "  ")).([]byte)
+	rw.Write(envJSON)
+}
+
+func HandleError(result interface{}, err error) (r interface{}) {
+	if err != nil {
+		panic(err)
+	}
+	return result
+}
+
+func main() {
+	pool = simpleredis.NewConnectionPoolHost(os.Getenv("SERVICE_HOST") + ":" + os.Getenv("REDIS_MASTER_SERVICE_PORT"))
+	defer pool.Close()
+
+	r := mux.NewRouter()
+	r.Path("/lrange/{key}").Methods("GET").HandlerFunc(ListRangeHandler)
+	r.Path("/rpush/{key}/{value}").Methods("GET").HandlerFunc(ListPushHandler)
+	r.Path("/info").Methods("GET").HandlerFunc(InfoHandler)
+	r.Path("/env").Methods("GET").HandlerFunc(EnvHandler)
+
+	n := negroni.Classic()
+	n.UseHandler(r)
+	n.Run(":3000")
+}

examples/guestbook-go/_src/public/index.html

@@ -0,0 +1,34 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta content="text/html; charset=utf-8" http-equiv="Content-Type">
+    <meta charset="utf-8">
+    <meta content="width=device-width" name="viewport">
+    <link href="/style.css" rel="stylesheet">
+    <title>Guestbook</title>
+  </head>
+  <body>
+    <div id="header">
+      <h1>Guestbook</h1>
+    </div>
+
+    <div id="guestbook-entries">
+      <p>Waiting for database connection...</p>
+    </div>
+
+    <div>
+      <form id="guestbook-form">
+        <input autocomplete="off" id="guestbook-entry-content" type="text">
+        <a href="#" id="guestbook-submit">Submit</a>
+      </form>
+    </div>
+
+    <div>
+      <p><h2 id="guestbook-host-address"></h2></p>
+      <p><a href="/env">/env</a>
+      <a href="/info">/info</a></p>
+    </div>
+    <script src="//ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
+    <script src="/script.js"></script>
+  </body>
+</html>

examples/guestbook-go/_src/public/script.js

@@ -0,0 +1,46 @@
+$(document).ready(function() {
+  var headerTitleElement = $("#header h1");
+  var entriesElement = $("#guestbook-entries");
+  var formElement = $("#guestbook-form");
+  var submitElement = $("#guestbook-submit");
+  var entryContentElement = $("#guestbook-entry-content");
+  var hostAddressElement = $("#guestbook-host-address");
+
+  var appendGuestbookEntries = function(data) {
+    entriesElement.empty();
+    $.each(data, function(key, val) {
+      entriesElement.append("<p>" + val + "</p>");
+    });
+  }
+
+  var handleSubmission = function(e) {
+    e.preventDefault();
+    var entryValue = entryContentElement.val()
+    if (entryValue.length > 0) {
+      entriesElement.append("<p>...</p>");
+      $.getJSON("rpush/guestbook/" + entryValue, appendGuestbookEntries);
+    }
+    return false;
+  }
+
+  // colors = purple, blue, red, green, yellow
+  var colors = ["#549", "#18d", "#d31", "#2a4", "#db1"];
+  var randomColor = colors[Math.floor(5 * Math.random())];
+  (function setElementsColor(color) {
+    headerTitleElement.css("color", color);
+    entryContentElement.css("box-shadow", "inset 0 0 0 2px " + color);
+    submitElement.css("background-color", color);
+  })(randomColor);
+
+  submitElement.click(handleSubmission);
+  formElement.submit(handleSubmission);
+  hostAddressElement.append(document.URL);
+
+  // Poll every second.
+  (function fetchGuestbook() {
+    $.getJSON("lrange/guestbook").done(appendGuestbookEntries).always(
+      function() {
+        setTimeout(fetchGuestbook, 1000);
+      });
+  })();
+});

examples/guestbook-go/_src/public/style.css

@@ -0,0 +1,61 @@
+body, input {
+  color: #123;
+  font-family: "Gill Sans", sans-serif;
+}
+
+div {
+  overflow: hidden;
+  padding: 1em 0;
+  position: relative;
+  text-align: center;
+}
+
+h1, h2, p, input, a {
+  font-weight: 300;
+  margin: 0;
+}
+
+h1 {
+  color: #BDB76B;
+  font-size: 3.5em;
+}
+
+h2 {
+  color: #999;
+}
+
+form {
+  margin: 0 auto;
+  max-width: 50em;
+  text-align: center;
+}
+
+input {
+  border: 0;
+  border-radius: 1000px;
+  box-shadow: inset 0 0 0 2px #BDB76B;
+  display: inline;
+  font-size: 1.5em;
+  margin-bottom: 1em;
+  outline: none;
+  padding: .5em 5%;
+  width: 55%;
+}
+
+form a {
+  background: #BDB76B;
+  border: 0;
+  border-radius: 1000px;
+  color: #FFF;
+  font-size: 1.25em;
+  font-weight: 400;
+  padding: .75em 2em;
+  text-decoration: none;
+  text-transform: uppercase;
+  white-space: normal;
+}
+
+p {
+  font-size: 1.5em;
+  line-height: 1.5;
+}

examples/guestbook-go/_src/script/build.sh

@@ -0,0 +1,35 @@
+#!/bin/bash
+
+# Copyright 2014 Google Inc. All rights reserved.
+#
+# 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.
+
+# Usage: ./script/build.sh
+
+set -o errexit
+set -o nounset
+set -o pipefail
+
+if [[ "${DOCKER_BIN+set}" == "set" ]]; then
+  echo "Using DOCKER_BIN=\"${DOCKER_BIN}\" from the environment."
+elif DOCKER_BIN=$(which docker); then
+  echo "Setting DOCKER_BIN=\"${DOCKER_BIN}\" from host machine."
+else
+  echo "Could not find a working docker binary and none passed in DOCKER_BIN." >&2
+  exit 1
+fi
+
+docker build --rm --force-rm -t kubernetes/guestbook-build .
+docker run --rm -v "${DOCKER_BIN}:/usr/local/bin/docker" \
+                -v "/var/run/docker.sock:/var/run/docker.sock" \
+                -ti --name guestbook-build kubernetes/guestbook-build

examples/guestbook-go/_src/script/clean.sh

@@ -0,0 +1,25 @@
+#!/bin/bash
+
+# Copyright 2014 Google Inc. All rights reserved.
+#
+# 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.
+
+# Usage: ./script/clean.sh
+
+set -o errexit
+set -o nounset
+set -o pipefail
+
+docker rm -f guestbook-build 2> /dev/null || true
+docker rmi -f kubernetes/guestbook-build || true
+docker rmi -f kubernetes/guestbook || true

examples/guestbook-go/_src/script/push.sh

@@ -0,0 +1,24 @@
+#!/bin/bash
+
+# Copyright 2014 Google Inc. All rights reserved.
+#
+# 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.
+
+# Usage: ./script/push.sh [TAG]
+
+set -o errexit
+set -o nounset
+set -o pipefail
+
+guestbook_version=${1:-latest}
+docker push "kubernetes/guestbook:${guestbook_version}"

examples/guestbook-go/_src/script/release.sh

@@ -0,0 +1,40 @@
+#!/bin/bash
+
+# Copyright 2014 Google Inc. All rights reserved.
+#
+# 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.
+
+# Usage: ./script/release.sh [TAG]
+
+set -o errexit
+set -o nounset
+set -o pipefail
+
+base_dir=$(dirname "$0")
+base_dir=$(cd "${base_dir}" && pwd)
+
+guestbook_version=${1:-latest}
+
+echo " ---> Cleaning up before building..."
+"${base_dir}/clean.sh" 2> /dev/null
+
+echo " ---> Building..."
+"${base_dir}/build.sh"
+
+echo " ---> Pushing kubernetes/guestbook:${guestbook_version}..."
+"${base_dir}/push.sh" "${guestbook_version}"
+
+echo " ---> Cleaning up..."
+"${base_dir}/clean.sh"
+
+echo " ---> Done."

examples/guestbook-go/guestbook-controller.json

@@ -0,0 +1,24 @@
+{
+  "apiVersion": "v1beta1",
+  "kind": "ReplicationController",
+  "id": "guestbook-controller",
+  "desiredState": {
+    "replicas": 3,
+    "replicaSelector": { "name": "guestbook" },
+    "podTemplate": {
+      "desiredState": {
+        "manifest": {
+          "version": "v1beta1",
+          "id": "guestbook-controller",
+          "containers": [{
+            "image": "kubernetes/guestbook",
+            "name": "guestbook",
+            "ports": [{ "name": "http-server", "containerPort": 3000 }]
+          }],
+        }
+      },
+      "labels": { "name": "guestbook" }
+    },
+  },
+  "labels": { "name": "guestbook" }
+}

examples/guestbook-go/guestbook-service.json

@@ -0,0 +1,8 @@
+{
+  "apiVersion": "v1beta1",
+  "kind": "Service",
+  "id": "guestbook",
+  "port": 3000,
+  "containerPort": "http-server",
+  "selector": { "name": "guestbook" }
+}

examples/guestbook-go/redis-master-pod.json

@@ -0,0 +1,17 @@
+{
+  "apiVersion": "v1beta1",
+  "kind": "Pod",
+  "id": "redis-master-pod",
+  "desiredState": {
+    "manifest": {
+      "version": "v1beta1",
+      "id": "redis-master-pod",
+      "containers": [{
+        "name": "redis-master",
+        "image": "gurpartap/redis",
+        "ports": [{ "name": "redis-server", "containerPort": 6379 }]
+      }]
+    }
+  },
+  "labels": { "name": "redis", "role": "master" }
+}

examples/guestbook-go/redis-master-service.json

@@ -0,0 +1,8 @@
+{
+  "apiVersion": "v1beta1",
+  "kind": "Service",
+  "id": "redis-master",
+  "port": 6379,
+  "containerPort": "redis-server",
+  "selector": { "name": "redis", "role": "master" }
+}

examples/guestbook-go/redis-slave-controller.json

@@ -0,0 +1,25 @@
+{
+  "apiVersion": "v1beta1",
+  "kind": "ReplicationController",
+  "id": "redis-slave-controller",
+  "desiredState": {
+    "replicas": 2,
+    "replicaSelector": { "name": "redis", "role": "slave" },
+    "podTemplate": {
+      "desiredState": {
+        "manifest": {
+          "version": "v1beta1",
+          "id": "redis-slave-controller",
+          "containers": [{
+            "name": "redis-slave",
+            "image": "gurpartap/redis",
+            "command": ["sh", "-c", "redis-server /etc/redis/redis.conf --slaveof $SERVICE_HOST $REDIS_MASTER_SERVICE_PORT"],
+            "ports": [{ "name": "redis-server", "containerPort": 6379 }]
+          }]
+        }
+      },
+      "labels": { "name": "redis", "role": "slave" }
+    }
+  },
+  "labels": { "name": "redis", "role": "slave" }
+}

examples/guestbook-go/redis-slave-service.json

@@ -0,0 +1,9 @@
+{
+  "apiVersion": "v1beta1",
+  "kind": "Service",
+  "id": "redis-slave",
+  "port": 6379,
+  "containerPort": "redis-server",
+  "labels": { "name": "redis", "role": "slave" },
+  "selector": { "name": "redis", "role": "slave" }
+}