Docker configuration for selenium tests

Why docker for selenium testers:

Usually while configuring the Selenium grid we need to host multiple virtual machines as nodes and we need to connect every single node with the hub. Also, when we set up a normal grid we need to download the Selenium server jar file and run that jar file on each computer in which we are going to set up the Selenium grid.

This is costly and sometimes a time-consuming task for the testers. However, Docker helps us to solve cost-related and time-consuming problems.

Steps to create a automation project with the help of Docker:

-Create a Maven project

-Add selenium dependencies

-Create a class like below.This will print Google by executing test in container created from docker.

-Define and initialize a chromeStandAlone container in 4444 port.Below details gives details of docker.

Most used common Docker commands:

docker ps: Will give information of all containers running in the machine.

Docker Images: will show all current images

docker pull <image name>: image will be downloaded into machine.

Ex: docker pull selenium/standalone-chrome:87.0 (by specifying the version)

      docker pull selenium/standalone-chrome:latest(will pull the latest version)

we can directly get commands in docker hub. See below.

Docker run: Will deploy the image into container.

Now

Below is the commands we have to run and these are readily available in documentation.

Ex: Chrome

$ docker run -d -p 4444:4444 -v /dev/shm:/dev/shm selenium/standalone-chrome:4.0.0-beta-1-prerelease-20201208

 

·         d stands for run in background

·         4444/4444: means localport/containerport

·         -p: identifies 4444/4444 as port and redirects localport to containerport.

Note:

We can set up docker in two ways

1.       With executing commands manually one after other. In below link it is explained this way.

Docker Selenium Tutorial: How to Integrate Selenium Grid with Docker (softwaretestinghelp.com)

2.       Writing all configurations in docker file(.yml) then run that yml file through command prompt.This yaml is readily available in selenium git hub docker documentation.Always use the latest version.

Here is the link for sample compose file:

ddocker-selenium/docker-compose-v3.yml at trunk · SeleniumHQ/docker-selenium · GitHub

Using Compose is basically a three-step process:

1.      Define your app’s environment with a Dockerfile so it can be reproduced anywhere.

2.      Define the services that make up your app in docker-compose.yml so they can be run together in an isolated environment.

Run docker-compose up and Compose starts and runs your entire app

To increase the browsers count in chrome node:

Below is the link for official selenium documentation on docker;

GitHub - SeleniumHQ/docker-selenium: Docker images for the Selenium Grid Server