24 Jan 2014


Have you ever wished your front end testing could be sped up? Has it ever seemed like Selenium was a royal pain in the ass? Though I agree, this isn’t the post that will relieve those problems. What it is, is a way to make testing your Angular app slightly less painful by providing light weight Selenium grid node parallelization with Protractor and Docker.

Specifically, this post will…

Interested in skipping to the end?

One last note before I get started… Francisco Martinez deserves all of the credit for figuring out how to integrate Protractor and concurrency in Grunt; I’m just writing up his work and cramming another Docker prototype into a blog bost. Thanks Francisco.

Get started with Selenium Grid (in a single vagrant vm)

I’ve put together two projects to supply the Selenium Grid functionality. The docker-selenium-grid project supplies Dockerfiles for two Docker containers: a hub and a Firefox node; and comes with a script to help you add start and stop the cluster or new nodes. The vagrant-selenium-grid project is a Vagrant wrapper for the first project which further simplifies starting a cluster to simply running vagrant up.

To boot your cluster, simply run the following commands

git clone https://github.com/benschw/vagrant-selenium-grid
cd vagrant-selenium-grid
vagrant up

This VM defaults to using 2gb of ram, but this can easily be tuned by tweaking the Vagrantfile before running vagrant up. It will run three firefox nodes by default, but you can tweak this by shelling into the Vagrant vm and interacting with the cluster via ~/docker-selenium-grid/grid.sh

If you want to make sure it works, install protractor and run ./test.sh

npm install -g protractor

Why Docker?

Docker provide’s lighweight virtualization. In other words, your laptop is probably capable of driving a handfull of browsers at once, but not a handfull of VMs. Docker gives you to encapsulation of a VM with (almost) none of the overhead. It does require a Linux kernel however, which is why i’ve recommended running your grid inside a Vagrant vm.

Running Linux? Skip the VM and run docker-selenium-grid on your host (you’ll just have to install Docker first.)

Concurrent Protractor Testing

Yo Angular!

I’ll assume you’ve used Yeoman before, but just in case - here’s how to get it:

sudo npm install -g yo
sudo npm install -g grunt-cli
sudo npm install -g bower

Now that you have the basics, lets use our new tools to generate an angular app:

mkdir protractor-demo
cd protractor-demo

npm install generator-angular

yo angular # go ahead and "Y" everything

This sets up Yeoman’s opinionated default angular app. Deps are installed with bower and a build script is provided that can be run with grunt.

Introducing Protractor

Now lets start adding in Protractor.

Install the npm deps:

sudo npm install -g protractor
npm install protractor --save-dev
npm install grunt-protractor-runner --save-dev

Add some tests and Update your build

At this point you can decide if you want to follow along and patch your Gruntfile.js by hand, or just grab a copy from the protractor-demo project. Additionally, I’ve included scenario.tar.bz2 which holds the example tests we will be wiring up.

The quick way:

wget -N https://raw.github.com/benschw/protractor-demo/master/Gruntfile.js
wget -qO- https://github.com/benschw/protractor-demo/raw/master/scenario.tar.bz2 | tar -C ./test/ -xjvf -

What are the changes?

Add in your Protractor test wiring after the “karma” section:

    protractor: {
      options: {
        //configFile: 'node_modules/protractor/referenceConf.js', // Default config file
        keepAlive: true, // If false, the grunt process stops when the test fails.
        noColor: false, // If true, protractor will not use colors in its output.
        args: {
          baseUrl: 'http://'+getIpAddress()+':'+ '<%= connect.dist.options.port %>' //config for all protractor tasks
      feature1: {
        options: {
          configFile:'test/scenario/conf/featureList1.js', // Target-specific config file
      feature2: {
        options: {
          configFile:'test/scenario/conf/featureList2.js', // Target-specific config file

Provide the getIpAddress() function at the top of your file. Since your grid is running in a VM, we need to give it more than localhost to target:

	var os = require('os');

	function getIpAddress() {
	  var ipAddress = null;
	  var ifaces = os.networkInterfaces();

	  function processDetails(details) {
	    if (details.family === 'IPv4' && details.address !== '' && !ipAddress) {
	      ipAddress = details.address;

	  for (var dev in ifaces) {
	  return ipAddress;

Reference our two test features in the “concurrent” section:

      protractor: [

In the “connect” section, update “connect.options” to use hostname: '', and “connect.dist” to use port: 9002

    connect: {
      options: {
        port: 9000,
        // Change this to '' to access the server from outside.
        hostname: '',
        livereload: 35729
      dist: {
        options: {
          port: 9002,
          base: '<%= yeoman.dist %>'

And last but not least, add a new task at the bottom of the file so we can run these bad boys:

	grunt.registerTask('ptr', [

Run the tests… Fast!

Assuming all our updates made it in and Yeoman’s Angular generator hasn’t changed, we should now be able to run tests for our two test features concurrently:

grunt ptr

I hope it worked for you, and I hope this helped.

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