chapter6

Signed-off-by: Peng Xiao <[email protected]>

chapter6/Vagrantfile

@@ -0,0 +1,34 @@
+# -*- mode: ruby -*-
+# vi: set ft=ruby :
+
+Vagrant.require_version ">= 1.6.0"
+
+boxes = [
+    {
+        :name => "docker-host",
+        :eth1 => "192.168.205.10",
+        :mem => "1024",
+        :cpu => "1"
+    }
+]
+
+Vagrant.configure(2) do |config|
+
+  config.vm.box = "centos/7"
+  boxes.each do |opts|
+    config.vm.define opts[:name] do |config|
+      config.vm.hostname = opts[:name]
+      config.vm.provider "vmware_fusion" do |v|
+        v.vmx["memsize"] = opts[:mem]
+        v.vmx["numvcpus"] = opts[:cpu]
+      end
+      config.vm.provider "virtualbox" do |v|
+        v.customize ["modifyvm", :id, "--memory", opts[:mem]]
+        v.customize ["modifyvm", :id, "--cpus", opts[:cpu]]
+      end
+      config.vm.network :private_network, ip: opts[:eth1]
+    end
+  end
+  config.vm.synced_folder "./labs", "/home/vagrant/labs"
+  config.vm.provision "shell", privileged: true, path: "./setup.sh"
+end

chapter6/labs/example-voting-app/README.md

@@ -0,0 +1,35 @@
+Example Voting App
+==================
+
+This is an example Docker app with multiple services. It is run with Docker Compose and uses Docker Networking to connect containers together. You will need Docker Compose 1.6 or later.
+
+More info at https://blog.docker.com/2015/11/docker-toolbox-compose/
+
+Architecture
+-----
+
+* A Python webapp which lets you vote between two options
+* A Redis queue which collects new votes
+* A Java worker which consumes votes and stores them in…
+* A Postgres database backed by a Docker volume
+* A Node.js webapp which shows the results of the voting in real time
+
+![pic](architecture.png)
+
+Running
+-------
+
+Run in this directory:
+
+    $ docker-compose up
+
+The app will be running on port 5000 on your Docker host, and the results will be on port 5001.
+
+Docker Hub images
+-----------------
+
+Docker Hub images for services in this app are built automatically from master:
+
+ - [docker/example-voting-app-voting-app](https://hub.docker.com/r/docker/example-voting-app-voting-app/)
+ - [docker/example-voting-app-result-app](https://hub.docker.com/r/docker/example-voting-app-result-app/)
+ - [docker/example-voting-app-worker](https://hub.docker.com/r/docker/example-voting-app-worker/)

chapter6/labs/example-voting-app/docker-compose.yml

@@ -0,0 +1,56 @@
+version: "3"
+
+services:
+  voting-app:
+    build: ./voting-app/.
+    volumes:
+     - ./voting-app:/app
+    ports:
+      - "5000:80"
+    links:
+      - redis
+    networks:
+      - front-tier
+      - back-tier
+
+  result-app:
+    build: ./result-app/.
+    volumes:
+      - ./result-app:/app
+    ports:
+      - "5001:80"
+    links:
+      - db
+    networks:
+      - front-tier
+      - back-tier
+
+  worker:
+    build: ./worker
+    links:
+      - db
+      - redis
+    networks:
+      - back-tier
+
+  redis:
+    image: redis
+    ports: ["6379"]
+    networks:
+      - back-tier
+
+  db:
+    image: postgres:9.4
+    volumes:
+      - "db-data:/var/lib/postgresql/data"
+    networks:
+      - back-tier
+
+volumes:
+  db-data:
+
+networks:
+  front-tier:
+  back-tier:
+
+

chapter6/labs/example-voting-app/result-app/Dockerfile

@@ -0,0 +1,15 @@
+FROM node:0.10
+
+RUN mkdir /app
+WORKDIR /app
+
+ADD package.json /app/package.json
+RUN npm install && npm ls
+RUN mv /app/node_modules /node_modules
+
+ADD . /app
+
+ENV PORT 80
+EXPOSE 80
+
+CMD ["node", "server.js"]

chapter6/labs/example-voting-app/result-app/package.json

@@ -0,0 +1,20 @@
+{
+  "name": "result-app",
+  "version": "1.0.0",
+  "description": "",
+  "main": "server.js",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "author": "",
+  "license": "MIT",
+  "dependencies": {
+    "body-parser": "^1.14.1",
+    "cookie-parser": "^1.4.0",
+    "express": "^4.13.3",
+    "method-override": "^2.3.5",
+    "async": "^1.5.0",
+    "pg": "^4.4.3",
+    "socket.io": "^1.3.7"
+  }
+}

chapter6/labs/example-voting-app/result-app/server.js

@@ -0,0 +1,78 @@
+var express = require('express'),
+    async = require('async'),
+    pg = require("pg"),
+    cookieParser = require('cookie-parser'),
+    bodyParser = require('body-parser'),
+    methodOverride = require('method-override'),
+    app = express(),
+    server = require('http').Server(app),
+    io = require('socket.io')(server);
+
+io.set('transports', ['polling']);
+
+var port = process.env.PORT || 4000;
+
+io.sockets.on('connection', function (socket) {
+
+  socket.emit('message', { text : 'Welcome!' });
+
+  socket.on('subscribe', function (data) {
+    socket.join(data.channel);
+  });
+});
+
+async.retry(
+  {times: 1000, interval: 1000},
+  function(callback) {
+    pg.connect('postgres://postgres@db/postgres', function(err, client, done) {
+      if (err) {
+        console.error("Failed to connect to db");
+      }
+      callback(err, client);
+    });
+  },
+  function(err, client) {
+    if (err) {
+      return console.err("Giving up");
+    }
+    console.log("Connected to db");
+    getVotes(client);
+  }
+);
+
+function getVotes(client) {
+  client.query('SELECT vote, COUNT(id) AS count FROM votes GROUP BY vote', [], function(err, result) {
+    if (err) {
+      console.error("Error performing query: " + err);
+    } else {
+      var data = result.rows.reduce(function(obj, row) {
+        obj[row.vote] = row.count;
+        return obj;
+      }, {});
+      io.sockets.emit("scores", JSON.stringify(data));
+    }
+
+    setTimeout(function() {getVotes(client) }, 1000);
+  });
+}
+
+app.use(cookieParser());
+app.use(bodyParser());
+app.use(methodOverride('X-HTTP-Method-Override'));
+app.use(function(req, res, next) {
+  res.header("Access-Control-Allow-Origin", "*");
+  res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
+  res.header("Access-Control-Allow-Methods", "PUT, GET, POST, DELETE, OPTIONS");
+  next();
+});
+
+app.use(express.static(__dirname + '/views'));
+
+app.get('/', function (req, res) {
+  res.sendFile(path.resolve(__dirname + '/views/index.html'));
+});
+
+server.listen(port, function () {
+  var port = server.address().port;
+  console.log('App running on port ' + port);
+});