Testing EmberJS app in Chrome in Docker

Assuming you already have an ember-cli app. First, let's create a Dockerfile:

# Dockerfile

FROM node:10-alpine

RUN npm install -g ember-cli

RUN \
  echo http://dl-3.alpinelinux.org/alpine/edge/main >> /etc/apk/repositories  && \
  apk add chromium

WORKDIR /myapp

COPY . /myapp/

RUN yarn

CMD ["ember", "test"]

Then you will need to alter your application testem.js. Note that we are not using Chrome, but Chromium:

module.exports = {
  test_page: 'tests/index.html?hidepassed',
  disable_watching: true,
  launch_in_ci: [
    'Chromium'
  ],
  launch_in_dev: [
    'Chromium'
  ],
  browser_args: {
    Chromium: {
      ci: [
        // --no-sandbox is needed when running Chrome inside a container
        // process.env.CI ? '--no-sandbox' : null,
        '--no-sandbox',
        '--headless',
        '--disable-gpu',
        '--disable-dev-shm-usage',
        '--disable-software-rasterizer',
        '--mute-audio',
        '--remote-debugging-port=0',
        '--window-size=1440,900'
      ].filter(Boolean)
    }
  }
};

Build your container:

$ docker build -t myapp .

And after this your tests should be able to run:

$ docker run myapp 
Could not start watchman
Visit https://ember-cli.com/user-guide/#watchman for more info.
cleaning up...
Built project successfully. Stored in "/myapp/tmp/class-tests_dist-RpV40XiD.tmp".
ok 1 Chrome 68.0 - [3 ms] - ESLint | app: app.js
ok 2 Chrome 68.0 - [0 ms] - ESLint | app: resolver.js
ok 3 Chrome 68.0 - [0 ms] - ESLint | app: router.js
ok 4 Chrome 68.0 - [0 ms] - ESLint | tests: test-helper.js
ok 5 Chrome 68.0 - [2 ms] - ember-qunit: Ember.onerror validation: Ember.onerror is functioning properly

1..5
# tests 5
# pass  5
# skip  0
# fail  0

# ok

Comments

[thisismydesign]

For me this fails with "Failed to read DnsConfig." I could only find this question but no solution: stackoverflow.com/questions/548383...

[John Costanzo]

What do you do for watchman? Is there concern on file size of image with chromium installed?

[Michal Bryxí]

If there is a need for watchman, it is certainly possible to install it. Last time I checked Apline and Debian had quite straightforward installation.

The image sizes are nothing small TBH, but gives you the whole UI testing options. Storage space is cheap, so never considered that an issue.