Automate Docker builds using Jenkins - Dockerize Python App | Upload Images into AWS ECR

We will learn how to automate Docker builds using Jenkins. We will use Python based application. I have already created a repo with source code + Dockerfile. We will see how to create Docker image and upload into AWS ECR successfully.

- Automating builds
- Automating Docker image creation
- Automating Docker image upload into AWS ECR
- Automating Docker container provisioning

Pre-requisites:
1. Jenkins is up and running
2. Docker installed on Jenkins instance
3. Docker and Docker pipelines plug-in are installed  and Amazon ECR plug-in installed
4. Repo created in ECR, Click here to know how to do that.
5. port 8096 is opened up in firewall rules.
6. Access keys + secret keys from AWS account

Step # 1 - Add ECR Plug-in
Go to Jenkins, Manage Jenkins, Add Amazon ECR plug-in

Step #2 - Create Credentials for AWS ECR
Go to your Jenkins where you have installed Docker as well.
Go to credentials -->

Click on Global credentials

Click on Add Credentials

Choose AWS credentials

Add your AWS access keys and secret keys and save it

Note down the ID after saving.

Step # 3 - Create a scripted pipeline in Jenkins, name can be anything

Step # 4 - Copy the pipeline code from below
Make sure you change red highlighted values below:
Your account_d should be updated and repo should be updated.
your registry credentials ID from Jenkins from step # 1 should be copied


pipeline {
    agent any
    environment {
        registry = "account_id.dkr.ecr.us-east-2.amazonaws.com/myphpapp"
        //- update your credentials ID after creating credentials for connecting to Docker Hub
        registryCredential = 'Copy_ID_from_step_no_1_above'
        dockerImage = ''
    }
   
    stages {
        stage('Cloning Git') {
            steps {
                checkout([$class: 'GitSCM', branches: [[name: '*/master']], doGenerateSubmoduleConfigurations: false, extensions: [], submoduleCfg: [], userRemoteConfigs: [[credentialsId: '', url: 'https://github.com/akannan1087/myPythonDockerRepo']]])      
            }
        }
   
    // Building Docker images
    stage('Building image') {
      steps{
        script {
          dockerImage = docker.build registry
            docker.build('myphpapp')
        }
      }
    }
    
     // Uploading Docker images into Docker Hub
    stage('Upload Image to ECR') {
     steps{   
         script {
            docker.withRegistry( 'https://account_id.dkr.ecr.us-east-2.amazonaws.com', "ecr:us-east-2:$registryCredential" ) {
            docker.image("myphpapp"). push('latest')
            }
        }
      }
    }
   
     // Stopping Docker containers for cleaner Docker run
     stage('stop previous containers') {
         steps {
            sh 'docker ps -f name=mypythonContainer -q | xargs --no-run-if-empty docker container stop'
            sh 'docker container ls -a -fname=mypythonContainer -q | xargs -r docker container rm'
         }
       }
     
    // Running Docker container, make sure port 8096 is opened in
    stage('Docker Run') {
     steps{
         script {
            dockerImage.run("-p 8096:5000 --rm --name mypythonContainer")
         }
      }
    }
  }
}

Step # 5 - Click on Build - Build the pipeline

Once you create the pipeline and changes values per your ECR account id and credentials ID, click on Build now.

Steps # 6 - Check Docker images are uploaded into ECR

Login to ECR, click on your repo, now you should image got uploaded.

Steps # 7 - Access PHP App

Once build is successful, go to browser and enter http://public_dns_name:8096

You should see page like below: