Deploying An Application Using Jenkinsfile

Deploying an application with a Jenkinsfile automates building, testing, and deploying the app. It ensures consistent and repeatable deployments, making CI/CD more efficient. Jenkins Pipeline Components:

• Pipeline: A series of stages and tasks for automated CI/CD defined in a Jenkinsfile.
• Stage: A part of the pipeline representing a phase, like build, test, or deploy.
• Trigger: An event, like a commit or manual action, that starts the pipeline.
• Workspace: A directory on the Jenkins agent for executing code, building artifacts, and storing temporary files.

Deploying An Application Using Jenkinsfile

Here are the steps for deploying an application.

Step 1: Log in to an AWS Account

• Navigate to AWS Console and login in with your credentials.
• Click on EC2 to go for EC2 Dashboard.

Step 2: Navigate to EC2 Dashboard

• Click on Running Instance to create a running instance.
• After landing, click on Create Instance.

Step 3: Launch Instance

• Define the sections such as providing the instance name as "my_jenkins_server" , no of instance as 1 and Choose the AMI as Amazon Linux 2 latest AMI.

Step 4: Configure Instance

• Choose the instance type as t2.micro and choose the existing key pair.
• If you don't have any key pair, click on create key pair and choose the key pair format type.

Step 5: Configure Network Security Groups

• Provide the network security groups by configuring them with allowing all traffic, so that they will no restrict of traffic from AWS. The following screenshot clearly illustrates that.

Step 6: Connect To Instance

• Review the provided definition and value. Once you confirmed with defined value click on Launch Instances.

Step 7: Connect To EC2 Console

• Wait till the instance come to running state, Once it been into the running state, Go through it and navigate to EC2 Console section.
• In the EC2 Console section click on connect.

Step 8: Install Jenkins

Now Install the jenkins and Java, with the following commands:

sudo wget -O /etc/yum.repos.d/jenkins.repo \
    https://pkg.jenkins.io/redhat-stable/jenkins.repo
sudo rpm --import https://pkg.jenkins.io/redhat-stable/jenkins.io-2023.key
sudo yum upgrade
# Add required dependencies for the jenkins package
sudo yum install java* -y 
sudo yum install jenkins
sudo systemctl daemon-reload

Step 9: Verify Java And Jenkins

Verify the successful installation of jenkins and java with following commands:

java --version
jenkins --version

Step 10: Start Jenkins Server

• Now, start the jenkins server with the following command:

systemctl enable jenkins --now

Step 11: Access Jenkins Server

After successfully starting the jenkins server, go to the browser and enter the following url, you will the see the below jenkins server page.

http:[IP_Address]:8080

Step 12: Copy Jenkins Password

• The jenkins server asks for password as for authentication, go through provided directory in the console and copy the password from their and paste in this url.
• After successful authentication, you will landed to Inside the Jenkins Server.

Step 13: Install Suggested Plugins

• Click on Install Suggest Plugins options, so it will help you in installing the required plugins already pre available before going for the jobs.

Step 14: Installation Of Plugins Completely

• The installation of suggested plugins takes some time, In the above page you can see the what are the plugins you are installing.

Step 15: Using Default Admin User

• After successfully installing the suggested plugins, It will ask for creating Admin user or go with default admin user. Here we are going with default admin user.

Step 16: Instance Configuration

• In the Instance Configuration page, you will see the url of the jenkins server page. With that provided url you can open the jenkins server from anywhere publicly.

Step 17: Create A Job

Now, create an item clicking on New Item in this Jenkins Web page.

Step 18: Configure The Job

• Now, Configure the jenkins item with defining the values such as Item name, And style such Pipeline project.

Step 19: Configure The Pipeline Job

• After navigating to Configure page, Enter into the Pipeline and then provided your application code their.
• Here, We are using the following code as a Jenkinsfile code. This code contains the stages such as Build, Test, Deploy Stages. After the execution of stages it mails status of pipeline whether it is successful or failure.

Note: Change the mail id with your one.

pipeline {
    agent any
    
    stages {
        stage('Build') {
            steps {
                sh 'echo "Building..."'
                sh 'mvn clean package'
            }
        }
        
        stage('Test') {
            steps {
                sh 'echo "Testing..."'
                sh 'mvn test'
            }
        }
        
        stage('Deploy') {
            steps {
                sh 'echo "Deploying..."'
                // Add deployment steps here
            }
        }
    }
    
    post {
        always {
            sh 'echo "Cleaning up..."'
        }
        
        success {
            mail to: '[email protected]',
                 subject: 'Pipeline Succeeded',
                 body: 'Your Jenkins Pipeline has completed successfully.'
        }
        
        failure {
            mail to: '[email protected]',
                 subject: 'Pipeline Failed',
                 body: 'Your Jenkins Pipeline has failed. Please investigate.'
        }
    }
}

• Once you configured the Jenkinfile application code, click on apply button.

Step 20: Successfully Jenkins Build

• After building the created jenkin job, you can see the successful running of the job with the below screenshot.