Selenium Federation

Introduction

selenium-federation is a cross-platform Selenium compatible testing solution that support browsers, electron apps and native apps automation for Desktop environment.

Key Fetures

• Easy to setup.
• Compatible with Selenium Webdriver protocol.
• Support CDP proxy (compatible with selenium-grid v4's).
• Compatible with popular test tools/frameworks like webdriver.io, testcafe, puppeteer, playwright etc.
• Support ansible style auto provisioning tasks.
• Support native apps automation via auto-cmd.
• Clean user-data automatically which allow you to run test for a long time without rebooting your machine.

Applicable scene

• You are in a development team that need to maintain a medium scale (less than 50 devices) test infrustructure by yourself.
• Your tests need to be executed on different OS and browsers.
• You have electron apps or native apps to test.
• You are a hacker that want to make your hands dirty to do something cool.

If those are not your cases, then you may consider other tools that implement the Selenium protocol.

Alternatives

• If you are finding a zero configuraion tool, you should try webdriver-manager or selenium-standalone.
• You should use selenium-grid or selenoid if
  • You are to setup an enterprise scale cluster that gonna to be used by multiple project teams.
  • You only have web apps to test.
  • You have mobile apps to test.

Quick Setup

Installation

npm install -g selenium-federation pm2 npm  # upgrade npm to avoid some wired issue

# Run the following command to read manuals
selenium-federation -h
sf-pm2-start -h
sf-test -h

Run Service in Foreground

You can use the following command to start selenium-federation in foreground. It's suggested to create a dedicated workspace to run the service, as it may create some folders and download resources to the current working directory.

# Create workspace
mkdir sf-workspace
cd sf-workspace

# For Windows 
selenium-federation -c https://raw.githubusercontent.com/link89/selenium-federation/main/examples/sample-win-local-config.yaml 

# For Mac OSX
selenium-federation -c https://raw.githubusercontent.com/link89/selenium-federation/main/examples/sample-mac-local-config.yaml 

selenium-federation only have one option to load configuration from local file or remote URL. All configuration options can be found in full-config-example.

And now your can run test on it with your favorite framework with the url http://localhost:4444/wd/hub. The base url /wd/hub is the same as selenium-grid's for the sake of compatiblity. Here is a simple example written with webdriver.io.

import { remote } from "webdriverio";

const opt = {
  hostname: 'localhost',
  port: 4444,
  path: '/wd/hub',
  capabilities: {
    browserName: 'chrome',
  }
};

(async () => {
  const driver = await remote(opt);
  await driver.url(`https://html5test.com/`);

  await new Promise(resolve => setTimeout(resolve, 5e3));
  await driver.deleteSession();
})();

Another way to verify the setup is to run the sf-test command,

sf-test --sf-url http://localhost:4444 

Run service in background with pm2

Foreground run is good for local debug as it prints logs in screen directly. But if you are to setup a test infrusturcture that will run for a long time, we provide another command to run service in pm2.

# Do forget to create workspace
mkdir sf-workspace
cd sf-workspace

# Run service in pm2
sf-pm2-start --name sf-local-01 -c local-config.yaml 

# check service status in pm2
pm2 ps

Compare with the previous example, everything is the same except a requirement field --name to specify an app name in the pm2. If you want to set more pm2 start options, you can pass them after --, for example

sf-pm2-start --name sf-local-01 -c local-config.yaml -- --restart-delay=3000

Start hub service

To start a hub service is very simple, here is a typeical configuration of hub.

role: hub
host: 0.0.0.0
port: 4444

fileServer: 
  root: .

Here we also start a fileServer with the hub node, you can access the file service via http://localhost:4444/fs/

Use Provision Task to Download Webdriver Binary

provision task is one of the key features of selenium-federation to simplify the system provision. It's inspired by ansible. The most common use case is to download webdriver binary automatically. For example,

provision:
  tasks:
    - download: https://registry.npmmirror.com/-/binary/chromedriver/101.0.4951.41/chromedriver_win32.zip
      cmds:
        - powershell Expand-Archive {download_file_path} -Force -DestinationPath .  # unpack to workspace

    - download: https://repo.huaweicloud.com/geckodriver/v0.31.0/geckodriver-v0.31.0-win64.zip
      cmds:
        - powershell Expand-Archive {download_file_path} -Force -DestinationPath .

    - neverSkip: true
      cmds:
        - npm outdated -g selenium-federation || ( npm install -g selenium-federation && throw_error_to_restart )

Here we define 2 tasks to download webdirver binary for Chrome and Firefox. And the last task is use to upgrade selenium-federation automatically.

You can also run ad-hoc provision task via /provision endpoint, for example:

curl -X POST -H "Content-Type: application/json" \
  -d '{"cmds":["unzip -o {download_file_path}"],"download":"https://msedgedriver.azureedge.net/102.0.1249.0/edgedriver_mac64.zip"}' \
  http://127.0.0.1:4444/provision

Please note that neverSkip will always be true when running task via API.

More example could be found in provision-task-gallery.

Termiate Service From Remote

You can access the page http://localhost:4444/termiate to terminate the selenium-federation from remote. This is useful when using with pm2. For example, you may change the configuration file (which is also in remote) and terminate the current process. pm2 will bring up the service automatically afterward with the latest configuration.

Test Execution

selenium-federation tries to keep compatible with Selenium and you can just run your existed Selenium test scripts on it. Besides of this, it provides some extra features to make it more powerful.