Late to the Party; End-to-End Testing: Part 5

We wrap up this series on some Sauce Labs specific features.

This article is part of a series on exploring end-to-end testing with Selenium and Node.js; starting with Late to the Party; End-to-End Testing: Part 1.

Sauce Labs Deep Integration

In a new folder, initialize a new Node.js project by entering (accepting all defaults):

npm init

Then in the project’s root folder install the WebdriverIO library with:

npm install webdriverio

We start by building a configuration to test against Sauce Lab’s service.

./node_modules/.bin/wdio config

The CLI walks you through a series of choices:

=========================
WDIO Configuration Helper
=========================
? Where do you want to execute your tests? In the cloud using Sauce Labs, Browserstack or Testingbot
? Environment variable for username SAUCE_USERNAME
? Environment variable for access key SAUCE_ACCESS_KEY
? Which framework do you want to use? mocha
? Shall I install the framework adapter for you? Yes
? Where are your test specs located? ./test/specs/**/*.js
? Which reporter do you want to use?  dot - https://github.com/webdriverio/wdio-dot-reporter
? Shall I install the reporter library for you? Yes
? Do you want to add a service to your test setup?  sauce - https://github.com/webdriverio/wdio-sauce-service
? Shall I install the services for you? Yes
? Level of logging verbosity silent
? In which directory should screenshots gets saved if a command fails? ./errorShots/
? What is the base url? http://localhost

As before, we update wdio.conf.js

• browserName: ‘chrome’
• sync: false

We also install chai.

npm install chai

and add the before hook into

wdio.conf.js

...
before: function() {
  const chai = require('chai');
  global.expect = chai.expect;
  chai.Should();
}
...

To enable Sauce Labs integration, we add a line (bold) to

wdio.confi.js

...
sauceConnect: true,
user: process.env.SAUCE_USERNAME,
key: process.env.SAUCE_ACCESS_KEY,
...

We write our test as before:

test/specs/hello.js

With our Sauce Labs username and access key, we can run our test:

SAUCE_USERNAME=OBMITTTED SAUCE_ACCESS_KEY=OBMITTED ./node_modules/.bin/wdio wdio.conf.js

As you can see the session is named based on the describe block in our test file and the status reports as passed (or failed should it fail).

Concurrency and Organizing Tests

Before you attempt to run more than one test at a time, you need to update wdio.conf.js to reflect the maximum number of concurrent sessions your Selenium server (Sauce Labs) supports, e.g., for two concurrent sessions:

• maxInstances: 2 (both overall and per browser)

With this in place, Testrunner will create a session (instance) for each test file you write and will automatically use multiple sessions (up to the limits) to minimize the length of time it takes to complete all the tests.

Within a file you can have multiple describe blocks each with multiple tests; regardless these will all run in the same session.

Conclusion

At this point, we have enough information to begin writing end-to-end tests in a scalable way (just need to arrange to have a sufficient number of concurrent sessions available).

So what about writing integration tests; say you had a React application that uses an API but you only were really interested in testing the React application in isolation. Sauce Labs has a solution provided in their Custom Sauce Labs WebDriver Extensions for Network and Log Commands. Will write up about this later in a separate article.

✉️ Subscribe to CodeBurst’s once-weekly Email Blast, 🐦 Follow CodeBurst on Twitter, view 🗺️ The 2018 Web Developer Roadmap, and 🕸️ Learn Full Stack Web Development.