How can I set up parallel testing with Selenium using Docker Compose?

How can I set up parallel testing with Selenium using Docker Compose?

To set up parallel testing with Selenium using Docker Compose, you need to define services for your Selenium Grid and your test containers in a docker-compose.yml file.

What should my docker-compose.yml file look like?

Here's a basic example:

version: '3'
services:
  selenium-hub:
    image: selenium/hub
    ports:
      - "4444:4444"
  chrome:
    image: selenium/node-chrome
    depends_on:
      - selenium-hub
    environment:
      - HUB_HOST=selenium-hub
  firefox:
    image: selenium/node-firefox
    depends_on:
      - selenium-hub
    environment:
      - HUB_HOST=selenium-hub

How do I run my tests in parallel once the setup is done?

You can use a test framework like TestNG or JUnit with Selenium to run your tests in parallel. Just configure the parallel execution in your test configuration.

Can you give me an example of a TestNG configuration for parallel execution?

Sure! Here's an example of a TestNG XML configuration:

<suite name="ParallelTests" parallel="tests" thread-count="2">
  <test name="Test1">
    <classes>
      <class name="com.example.TestClass1"/>
    </classes>
  </test>
  <test name="Test2">
    <classes>
      <class name="com.example.TestClass2"/>
    </classes>
  </test>
</suite>