How do I execute tests using a headless browser?

Other Questions Headless Browser
1

I’m working with Angular CLI and using the command ng test to run my tests. By default, it operates in Chrome, which is good, but I’m looking for a way to run my tests in a headless browser suitable for a console-only environment. It would also be preferable to have the option to specify whether I want to use a headless browser for each test run, such as executing the command like this: ng test --browsers MyHeadlessBrowser. Additionally, when I attempted to run the tests with PhantomJS, I encountered some errors. Specifically, I received a TypeError indicating that useValue, useFactory, and data are not iterable. I’m also facing a ReferenceError about not being able to find the variable ‘Intl’ in my vendor bundle. Any guidance on resolving these issues would be appreciated.

2

To run tests using a headless browser in Angular CLI, switch to Chrome Headless, which performs better than PhantomJS. Here’s a quick setup:

1. Install Chrome Headless:
Ensure Chrome is installed and up-to-date.

2. Modify karma.conf.js:

module.exports = (config) => {
  config.set({
    browsers: ['ChromeHeadless'],
    // other configurations...
  });
};

3. Run Tests:
Use the command:

ng test --browsers=ChromeHeadless

4. Fix ‘Intl’ Errors:
Run: npm install intl --save, then update your polyfills.ts:

import 'intl';
import 'intl/locale-data/jsonp/en';

This should resolve your issues and provide a smoother headless testing experience.

3

Running tests with a headless browser in Angular CLI can significantly improve your workflow in console environments. While earlier solutions suggested Chrome Headless, you might want to explore Puppeteer as a robust alternative that integrates seamlessly with Chrome for headless operations.

1. Set Up Puppeteer:
Install Puppeteer, which is a Node library that provides a high-level API over the Chrome DevTools Protocol, allowing it to manage and automate Chrome or Chromium.

npm install --save-dev puppeteer

2. Modify karma.conf.js for Puppeteer:

const puppeteer = require('puppeteer');
process.env.CHROME_BIN = puppeteer.executablePath();

module.exports = function(config) {
  config.set({
    browsers: ['ChromeHeadless'],
    customLaunchers: {
      ChromeHeadless: {
        base: 'Chrome',
        flags: ['--no-sandbox', '--headless', '--disable-gpu']
      }
    },
    // other configurations...
  });
};

3. Execute Tests:
Now, you can run your tests with:

ng test --browsers=ChromeHeadless

4. Addressing ‘Intl’ Errors:
For internationalization issues, consider not only installing but adding necessary polyfills for broader locale support.

npm install intl

Update your polyfills.ts:

import 'intl';
import 'intl/locale-data/jsonp/en'; // Add additional locales as required

By leveraging Puppeteer, you can further automate testing workflows while addressing headless browser limitations and internationalization issues effectively. This approach offers flexibility, avoiding some limitations if custom browser behavior is needed.

4

To execute tests using a headless browser in an Angular CLI environment, I recommend switching from PhantomJS to Chrome Headless, which is now more widely supported and allows for console-only operations.

Here’s a practical guide to implement this:

  1. Install Chrome Headless Dependencies:
    Ensure you have the latest version of Chrome. If not, you can download it following the instructions for your OS from here.

  2. Update your karma.conf.js file:
    You need to modify your Karma configuration file to use Chrome Headless. You can do this by adding ‘ChromeHeadless’ to the list of browsers.

    module.exports = function(config) {
  config.set({
    browsers: ['ChromeHeadless'],
    // other configurations...
  });
};

  3. Run tests with the headless option:
    You can execute your tests using the following command:

    ng test --browsers=ChromeHeadless

  4. Handling Errors with ‘Intl’:
    The issue related to ‘Intl’ often occurs in headless testing environments. A useful workaround is to include the intl package to your project and import it in your polyfills.ts file:

    npm install intl --save

    Then, modify your polyfills.ts to include:

    import 'intl';
import 'intl/locale-data/jsonp/en'; // Use the appropriate locale

Moving away from PhantomJS helps to avoid many common compatibility issues and aligns your test runs with modern development environments. By using Chrome Headless, you maintain the speed and reliability of your testing suite effectively in a headless setup.

5

To execute tests in a headless environment with Angular CLI, consider switching to Chromium or Chrome Headless. These are reliable for automation tasks and better supported than PhantomJS.

1. Install Required Dependencies:
Make sure you have Chrome installed. Puppeteer can also automate the process of launching a headless browser.

npm install --save-dev puppeteer

2. Update karma.conf.js:
Configure it to use Chrome in headless mode via Puppeteer.

const puppeteer = require('puppeteer');
process.env.CHROME_BIN = puppeteer.executablePath();

module.exports = function(config) {
  config.set({
    browsers: ['ChromeHeadless'],
    customLaunchers: {
      ChromeHeadless: {
        base: 'Chrome',
        flags: ['--headless', '--disable-gpu', '--no-sandbox']
      }
    },
    // additional configs...
  });
};

3. Execute Testing Command:
To run tests in headless mode, use:

ng test --browsers=ChromeHeadless

4. Resolve `Intl` Error:
PhantomJS lacks some standard library features. Here’s a fix:

npm install intl

Then, add these lines to your polyfills.ts:

import 'intl';
import 'intl/locale-data/jsonp/en';

Switching away from PhantomJS helps mitigate compatibility issues, while Puppeteer in headless Chrome optimizes reliability and speed in test automation.

6

To run Angular CLI tests using a headless browser, switch to Chrome Headless over PhantomJS for better support and performance.

1. Install Puppeteer:
This automates Chrome in headless mode:

npm install --save-dev puppeteer

2. Update karma.conf.js:

const puppeteer = require('puppeteer');
process.env.CHROME_BIN = puppeteer.executablePath();

module.exports = (config) => {
  config.set({
    browsers: ['ChromeHeadless'],
    customLaunchers: {
      ChromeHeadless: {
        base: 'Chrome',
        flags: ['--headless', '--no-sandbox']
      }
    },
    // other configurations...
  });
};

3. Run Tests:
Execute:

ng test --browsers=ChromeHeadless

4. Fix `Intl` Errors:
Install `intl` package:

npm install intl --save

Add to polyfills.ts:

import 'intl';
import 'intl/locale-data/jsonp/en';

This approach improves compatibility and resolves your console environment issues efficiently.