Selenium Grid + Docker + AWS EC2

This is going to be a simple (and single) entry point for setting up and running Selenium Grid inside of Docker containers on AWS EC2.

So steps will be the next:

1. Create and start EC2 instance

2. Open port 4444 as it’s used by the grid through the adding needed security rule:

    I. Open the Amazon EC2 console at https://console.aws.amazon.com/ec2/

    II. In the navigation pane, choose the Security Groups link. 

    III. Select the Inbound tab, choose Edit.

    IV. In the dialog, choose Add Rule and do the following:

        - Type: Custom TCP
        - Protocol: TCP
        - Part Range: 4444
        - Source: My IP
        - Description: Selenium Grid (or any other one)

Once the Selenium Grid is up and running, if 52.222.124.100 (for example) is the public facing IP address  connecting to http://52.222.124.100:4444/grid/console will connect to the console.

Login into and install Docker:

Install Docker on the AWS instance: 

$ sudo yum install -y docker

Start the docker service: 

$ sudo service docker start

Add the ec-2-user to the Docker group: 

$ sudo usermod -a -G docker ec2-user

Close the Mac Terminal and reopen it to reset permissions.

Setting up grid (images from https://hub.docker.com/u/selenium/ & instructions from https://github.com/SeleniumHQ/docker-selenium)

$ docker network create grid

$ docker run -d -p 4444:4444 --net grid --name selenium-hub selenium/hub:3.11.0-bismuth

$ docker run -d --net grid -e HUB_HOST=selenium-hub -v /dev/shm:/dev/shm selenium/node-chrome:3.11.0-bismuth

$ docker run -d --net grid -e HUB_HOST=selenium-hub -v /dev/shm:/dev/shm selenium/node-firefox:3.11.0-bismuth

With docker-compose file it will be easier.

Install docker-compose:

$ sudo curl -L https://github.com/docker/compose/releases/download/1.20.1/docker-compose-'uname -s'-'uname -m' -o /usr/local/bin/docker-compose

$ sudo chmod +x /usr/local/bin/docker-compose

In home directory (directory from where You’re starting grid):

$ touch docker-compose.yaml

Paste next content (example from SeleniumHQ)

---------------------------------------------------------------------------

# To execute this docker-compose yml file use docker-compose -f <file_name> up  

 # Add the "-d" flag at the end for deattached execution  

 version: '2'  

 services:  

  firefox:  

   image: selenium/node-firefox:3.11.0-bismuth  

   volumes:  

    - /dev/shm:/dev/shm  

   depends_on:  

    - hub  

   environment:  

    HUB_HOST: hub  

   

  chrome:  

   image: selenium/node-chrome:3.11.0-bismuth  

   volumes:  

    - /dev/shm:/dev/shm  

   depends_on:  

    - hub  

   environment:  

    HUB_HOST: hub  

   

  hub:  

   image: selenium/hub:3.11.0-bismuth  

   ports:  

    - "4444:4444"  

---------------------------------------------------------------------------

$ docker-compose up -d - to start grid

$ docker-compose down - to stop grid

If needed more than 1 node either for Chrome or Firefox just add the entry into docker-compose file.

Example of usage will be something like that from Your selenium setup (for Jenkins it can be done separately):

@BeforeMethod(alwaysRun = true)

public void setupBaseTest() throws Exception {

    DesiredCapabilities dr = null;

    dr = DesiredCapabilities.chrome();

    driver = new RemoteWebDriver(new URL("http://52.222.124.100:4444/grid/console"), dr);

}

Jenkins Build Server + AWS EC2

There are quite a few examples on the internet how to set Jenkins build server on the EC2 instance from AWS so I won't need to explicitly explain all steps and rather will put the list of them.

So first You'll need an AWS account which is abnormally easy to create. After that, we can proceed with launching a free EC2 instance (t2.micro) and assigning security groups to it.

1. Settings for EC2 instance:
- Network --> Default VPC (or Your custom one if You have it already)
- Subnet --> Default subnet (or Your public subnet if You have one)
- Auto-assign Public IP should be enabled
- Before launching instance go to Edit security groups --> add Your security group (if You have one, otherwise go to Create Security Group --> Add name & description --> Set Your VPC --> Add rule (create SSH, HTTP, Custom TCP Rule port should be 8080))
- Launch

2. Connect to the EC2 instance:
- After launching instance there's an option in the menu about how to connect to Your instance otherwise follow next steps
- $ ssh -i /path/my-key-pair.pem ec2-user@your-instance-public-address

3. Install and launch Jenkins
- $ sudo yum update -y (usually this is recommended step for all new instances of Amazon Linux)
- $ sudo wget -O /etc/yum.repos.d/jenkins.repo http://pkg.jenkins-ci.org/redhat/jenkins.repo (getting Jenkins package)

- $ sudo rpm --import https://pkg.jenkins.io/redhat/jenkins.io.key (import Jenkins key)

- $ sudo install jenkins -y

- $ sudo service jenkins start

- http://your-server-public-DNS:8080 (address for your Jenkins server)

- $ sudo cat /var/lib/jenkins/secrets/initialAdminPassword (initial Jenkins admin password)

After connecting to Jenkins it's recommended to setup Your password and install needed plugins (one from important list is Amazon EC2 plugin if You are planning to connect that instance to other AWS boxes)