Primary Technology: Github, Docker, Jenkins, aws EC2 service

Before we write any CI/CD pipeline we need an application to test and deploy. We are going to build a simple to-do application in node.js. Then, create new repository under your GitHub account and name it “node-todo-cicd”.

After logging into your AWS account, search for EC2

Select Instances(running)

Click Launch instances

Enter Name and select Ubuntu

Select t2.micro as Instance type and create new key pair to connect to the server

Enter key pair name and select RSA as Key pair type and .pem as Private key file format. Then, click Create key pair

Finally, click Launch instance

Click Connect on the top of the screen

Click Connect

Install Java using following commands:
sudo apt update
sudo apt install openjdk-22-jre
java -version

Install Jenkins using following commands:
**curl -fsSL https://pkg.jenkins.io/debian/jenkins.io.key | sudo tee \ /usr/share/keyrings/jenkins-keyring.asc > /dev/null **
echo deb [signed-by=/usr/share/keyrings/jenkins-keyring.asc] \ https://pkg.jenkins.io/debian binary/ | sudo tee \ /etc/apt/sources.list.d/jenkins.list > /dev/null
sudo apt-get update
sudo apt-get install jenkins

Start jenkins using following commands:
sudo systemctl enable jenkins
sudo systemctl start jenkins
sudo systemctl status jenkins

Go to Instances. Click on Security tab Click on the link below Security groups Click on Edit inbound rules Click on Add rule and add port 8080 and select My IP and then click Save rules

Open port 8080 on new tab

On console, type the command sudo cat /var/lib/jenkins/secrets/initialAdminPassword and copy the password

Paste the password in Administrator password to unlock jenkins

Install suggested plugins

Create First Admin User

Enter Jenkins URL and click Save and Finish

Finally, Jenkins is ready. Click on the button Start using Jenkins

Create new job by clicking New item

Enter an item name. Select Freestyle project. Add description. Select GitHub project and add project url

Select Git as Code Management and add Repository URL. Click on Add to add key

Generate SSH key on console using following commands:
ssh-keygen
cd .ssh
cat id_rsa_pub
Copy the public key

Go to GitHub. Click on Settings

Click on SSH and GPS keys on the left pane and click on Add SSH key

Paste the SSH key and click Add SSH key Go to Jenkins, and select SSH Username with private key in kind On console, enter the command cat id_rsa and copy the private key Paste the private key in jenkins wizard

Select ubuntu(This is for github and jenkins integration) in credentials

Enter */master in Branch Specifier and click Save

In jenkins, click on Build Now on the left pane

Now, click on #1 and select Console Output to view the console

To check whether we got the code on EC2 instance, go to console, and enter the following commands:
sudo cd /var/lib/jenkins/workspace/todo-node-app
ls
Clearly, the code is present in this directory

Click Add rule and enter port number 8000 and select Anywhere IPv4 it can be accessed by anyone. Click Save rules

On console, run the following commands:
sudo apt install nodejs
sudo apt install npm
npm install
node app.js

Remove Dockerfile and install Docker using following command:
sudo rm Dockerfile
sudo apt install docker.io

Edit Dockerfile using the command sudo vim Dockerfile and add following commands within it:
FROM node:12.2.0-alpine
WORKDIR app
COPY . .
RUN npm install
EXPOSE 8000
CMD ["node", "app.js"]

On console, enter the following commands: sudo usernod -a -G docker $USER
sudo reboot
To give permission to docker and reboot the system After restarting, enter the following command:
sudo build . -t todo-node-app

After building docker, enter the following command:
docker run -d --name node-todo-app -p 8000:8000 todo-node-app
To check status of container docker ps

On console, enter the following commands to terminate a container:
docker ps
docker kill

On jenkins, go to dashboard and select the project. For me, it is todo-node-app

Click on configure on the left pane

Click on Build Steps on the left pane and then select Execute shell in the Build Steps section

Enter the following commands in the Execute shell to be executed:
docker build . -t node-app-todo
docker run -d --name node-app-container -p 8000:8000 node-app-todo
Click Save

Click on Build Now on the left pane

On console, enter the following commands to terminate a container:
docker ps
docker kill

On jenkins, go to dashboard and select the project. For me, it is todo-node-app

Click on Manage Jenkins on the left pane and then click on Manage Plugins

Search for GitHub Integration and select GitHub Integration. Finally, click on Download without restart

On aws, go to instances and click on Security pane

Edit inbound traffic of port 8080 to Anywhere IPv4 and click Save rules

Go to GitHub and click Settings

Ensure that SSH and GPG keys are present on your GitHub account

Now, click on repository settings

Click on Webhooks on left pane and click on Add webhook to add a webhook

Add Payload URL and select content type as application/json

Finally, click Add webhook

Go to Jenkins Job and click on configure on left pane

Click on Build Triggers on left pane and enable **GitHub hook trigger for GITScm polling. Finally, click Save

Go to GitHub project repository and edit the project. Click Commit changes

Clearly, Jenkins pipeline are triggered as the code is pushed on GitHub