I recently set up an end-to-end testing stack to make sure I wasn't going to introduce any functional regressions to my blog. With several years of experience using E2E (End to End) testing technologies, I still encountered some difficulties in setting it up. In order to save you time, I have written you a step-by-step tutorial for the installation of the tools necessary to have an efficient test stack in a few minutes. Make it run locally first You need to install some dependencies to your project first. For me, the project was a quite simple Gatsby site, but you could settle it on whatever website you develop that has a file. In this case, I will start from a newly initialised package.json package. Make sure you have a Chromium or Chrome browser installed locally. We are really lucky because teams have developed a CLI topic that does this job for you. WebdriverIo yarn add -D @wdio/cli Then all you need is to trigger the initialisation of a new configuration. The CLI will show you a prompt you should follow. yarn wdio config Here is what you should do for each question: Select first . On my local machine You should definitely use . The Gherkin language is so great that it can . cucumber declare humanly readable user behaviors Choose the compiler you need, I personally use . You could decide if you want to handle Babel or Typescript depending on your habits. No For the I like to use the default value. Where are your feature files located? Same for step definitions, use the default value. Let's see what tests WebdriverIo will autogenerate. I wouldn't use that if it is the first time you’re setting up those kinds of testing stacks, say . Do you want to use page objects ? n You should select reporter here. spec Please select service only. chromedriver Override the base URL with your local context (for example, add the port on which you expose your app locally). Normally the CLI generates some files for you and adds the missing dependencies you need. Here is my package.json { "name": "example-wdio", "version": "1.0.0", "main": "index.js", "license": "MIT", "devDependencies": { "@wdio/cli": "^7.9.1", "@wdio/cucumber-framework": "^7.9.1", "@wdio/local-runner": "^7.9.1", "@wdio/spec-reporter": "^7.9.0", "chromedriver": "^92.0.1", "wdio-chromedriver-service": "^7.2.0" } } You should see a file in folder. login.feature ./features/ Feature: The Internet Guinea Pig Website Scenario Outline: As a user, I can log into the secure area Given I am on the login page When I login with <username> and <password> Then I should see a flash message saying <message> Examples: | username | password | message | | tomsmith | SuperSecretPassword! | You logged into a secure area! | | foobar | barfoo | Your username is invalid! | With the steps definitions in ./step-definitions/steps.js const { Given, When, Then } = require('@cucumber/cucumber') Given(/^I am on the (\w+) page$/, async (page) => { await browser.url(`https://the-internet.herokuapp.com/${page}`) }) When(/^I login with (\w+) and (.+)$/, async (username, password) => { await $('#username').setValue(username) await $('#password').setValue(password) await $('button[type="submit"]').click() }) Then(/^I should see a flash message saying (.*)$/, async (message) => { await expect($('#flash')).toBeExisting() await expect($('#flash')).toHaveTextContaining(message) }) Let's see what those default example tests are doing! For that, you just have to type this in your console and tada 🎉 yarn wdio run wdio.conf.js Here is the log it will generate thanks to the reporter! spec ------------------------------------------------------------------ [chrome 92.0.4515.131 mac os x #0-0] Running: chrome (v92.0.4515.131) on mac os x [chrome 92.0.4515.131 mac os x #0-0] Session ID: edd73da800a210e7c677c69cd064004f [chrome 92.0.4515.131 mac os x #0-0] [chrome 92.0.4515.131 mac os x #0-0] » /features/login.feature [chrome 92.0.4515.131 mac os x #0-0] The Internet Guinea Pig Website [chrome 92.0.4515.131 mac os x #0-0] As a user, I can log into the secure area [chrome 92.0.4515.131 mac os x #0-0] ✓ Given I am on the login page [chrome 92.0.4515.131 mac os x #0-0] ✓ When I login with tomsmith and SuperSecretPassword! [chrome 92.0.4515.131 mac os x #0-0] ✓ Then I should see a flash message saying You logged into a secure area! [chrome 92.0.4515.131 mac os x #0-0] [chrome 92.0.4515.131 mac os x #0-0] As a user, I can log into the secure area [chrome 92.0.4515.131 mac os x #0-0] ✓ Given I am on the login page [chrome 92.0.4515.131 mac os x #0-0] ✓ When I login with foobar and barfoo [chrome 92.0.4515.131 mac os x #0-0] ✓ Then I should see a flash message saying Your username is invalid! [chrome 92.0.4515.131 mac os x #0-0] [chrome 92.0.4515.131 mac os x #0-0] 6 passing (3s) For now, the tests are not testing your application at all. You will find many resources on how to use to write a great test to describe and test your application features. Cucumber JS Configure the Github action workflow Now that we have managed to run E2E tests on our machine, we just need to set up a continuous integration workflow that will automatically check on your Pull Request and on your branch that all the tests are ok. main I use it for most of my projects Github Action and I'm happy with it, so the following example will use this tool. However, the principle also works with Gitlab, Jenkins, or other pipelines. With Github Action you need to set up a Yaml file to describe your workflow. Let's create file in your project! ./.github/workflows/continuous-integration.yml name: Continuous Integration on: push: branches: - '**' jobs: build: runs-on: ubuntu-latest steps: # First you need to install a chromium browser in your runner - name: Install Chromium run: sudo apt-get install chromium-browser # You fetch the current ref - uses: actions/checkout@v2 # Use Node version above 14.x you want to use - name: Use Node.js uses: actions/setup-node@v1 with: node-version: 16.x # Install your dependencies (with yarn, npm no matter) - run: yarn install name: Install dependencies # This is where you could build your app # You could also start your server process (take a look at https://github.com/Slashgear/slashgear.github.io/blob/source/.github/workflows/continuous-integration.yml) # Run your test with the same command you uses locally - run: yarn wdio run wdio.conf.js name: Running E2E tests Let's try that! 🚀 😭 Sadly you should face a very common error with E2E testing with chrome. [0-0] 2021-08-12T20:34:12.293Z ERROR webdriver: Request failed with status 500 due to unknown error: unknown error: Chrome failed to start: exited abnormally. [0-0] (unknown error: DevToolsActivePort file doesn't exist) [0-0] (The process started from chrome location /usr/bin/google-chrome is no longer running, so ChromeDriver is assuming that Chrome has crashed.) [0-0] 2021-08-12T20:34:12.293Z ERROR webdriver: #0 0x5631c488ba63 <unknown> basically means your browser did not succeed to start. The main reason for the issue is the fact that you ask WebdriverIo to start Chrome browser with a Graphic User Interface on a ubuntu runner that doesn't have a screen at all 😅. DevToolsActivePort file doesn't exist We need to create a new configuration of Webdriver specific to GitHub action that extends our basic one. Let's create next to ! wdio-github.conf.js wdio.conf.js const basicConfig = require('./wdio.conf') exports.config = { ...basicConfig.config, // We only need to override the Chrome configuration of capabilities capabilities: [ { maxInstances: 5, browserName: 'chrome', acceptInsecureCerts: true, // We need to extends some Chrome flags in order to tell Chrome to run headless 'goog:chromeOptions': { args: ['--headless', '--disable-gpu', '--disable-dev-shm-usage'], }, }, ], } We now just have to change the command in our Github Workflow YAML file. You just need to push it and GitHub will start it for you! yarn wdio run Setup multi-browser configuration! Chrome is not the only browser, and I hope it never will never be! And I won't show you here what great features you could use with remote running solutions like or directly with WebdriverIo. BrowserStack Saucelabs Let's configure a Firefox locally! Make sure to install a Java JDK 8 on your machine. A small trick for macOS users like me run does the job! brew install adoptopenjdk/openjdk/adoptopenjdk8 Run to install selenium services working with WebdriverIo. yarn add -D @wdio/selenium-standalone-service Make sure you have Firefox installed locally. Now the last thing we need to do is to update our configuration to add firefox capabilities. In , just replace and arrays with this wdio.conf.js capabilities services { capabilites: [ { maxInstances: 5, browserName: 'chrome', acceptInsecureCerts: true, }, { maxInstances: 5, browserName: 'firefox', acceptInsecureCerts: true, } ], services: ['chromedriver', 'selenium-standalone'], } If you run the command now, it will trigger both tests on Firefox and Chrome and that is completely awesome! yarn wdio run wdio.conf.js The last thing we need to do is to update our Github-specific configuration in order to make it work also in your continuous integration. You need to update too, in order to add Firefox and to make it boot . capabilities Headless In wdio-github.conf.js const basicConfig = require('./wdio.conf') exports.config = { ...basicConfig.config, // We only need to override the Chrome configuration of capabilities capabilities: [ { maxInstances: 5, browserName: 'chrome', acceptInsecureCerts: true, // We need to extends some Chrome flags in order to tell Chrome to run headless 'goog:chromeOptions': { args: ['--headless', '--disable-gpu', '--disable-dev-shm-usage'], }, }, { maxInstances: 5, browserName: 'firefox', acceptInsecureCerts: true, 'moz:firefoxOptions': { args: ['-headless'], }, }, ], } And that's all folks ! Have fun covering your application with E2E tests! Don't hesitate to @ me on Twitter if this helped you. How to If you need to see the example application I used in this tutorial, take a look at . this example Github repository This article was first published on GitHub
