# Automating CI/CD with Jenkins: A Dockerized Approach

In today's fast-paced world of software development, the need for automation in building, testing, and deploying applications is more critical than ever. Continuous Integration (CI) and Continuous Deployment (CD) pipelines play a key role in streamlining these processes. In this blog post, we'll explore a Jenkins pipeline written in Groovy that leverages Docker to automate these tasks seamlessly.

#### Jenkins Pipeline Overview:

Our Jenkins pipeline consists of several stages, each serving a specific purpose:

1. **Code Stage:**
    
    ```plaintext
    groovyCopy codestage('code') {
        steps {
            git url: 'https://github.com/muhammadhassanb111/node-todo-cicd.git', branch: 'master'
        }
    }
    ```
    
    In this stage, we fetch the latest code from our GitHub repository, ensuring that we're always working with the most up-to-date version of our application.
    
2. **Build and Test Stage:**
    
    ```plaintext
    groovyCopy codestage('build and test') {
        steps {
            script {
                echo '=== Building Docker Image ==='
                sh 'docker build . -t hassanb111/node-todo-app:latest'
                echo '=== Docker Image Built ==='
                
                echo '=== Docker Images List ==='
                sh 'docker images'
                echo '=== End of Docker Images List ==='
            }
        }
    }
    ```
    
    In this stage, we build a Docker image from our application's Dockerfile. The process is accompanied by informative messages, and we list the Docker images for visibility.
    
3. **Login and Push Images Stage:**
    
    ```plaintext
    groovyCopy codestage('login and push images') {
        steps {
            echo 'Logging into Docker Hub'
            withCredentials([usernamePassword(credentialsId: 'dockerhub', passwordVariable: 'dockerhubpassword', usernameVariable: 'dockerhubuser')]) {
                sh "docker login -u ${env.dockerhubuser} -p ${env.dockerhubpassword}"
                sh "docker push hassanb111/node-todo-app:latest"
            }
        }
    }
    ```
    
    This stage handles the secure login to Docker Hub using Jenkins credentials and subsequently pushes the Docker image to the Docker Hub repository.
    
4. **Deploy Stage:**
    
    ```plaintext
    groovyCopy codestage('deploy') {
        steps {
            script {
                echo '=== Stopping and Removing Containers ==='
                sh 'docker-compose down'
                echo '=== Containers Stopped and Removed ==='
    
                echo '=== Starting Containers ==='
                sh 'docker-compose up -d'
                echo '=== Containers Started ==='
            }
        }
    }
    ```
    
    The final stage involves stopping and removing existing Docker containers and then initiating fresh containers using Docker Compose.
    
    ![](https://cdn.hashnode.com/res/hashnode/image/upload/v1703055382007/323eb73a-bcba-4175-a6fd-a78523dee770.png align="left")
    

![](https://cdn.hashnode.com/res/hashnode/image/upload/v1703055424161/6b6c8a88-ce23-4650-94b7-ac464fa6551c.png align="center")

![](https://cdn.hashnode.com/res/hashnode/image/upload/v1703055725607/444a0fa6-28a9-4e64-a413-ed3a6e62065c.png align="center")

![](https://cdn.hashnode.com/res/hashnode/image/upload/v1703055495544/f41d677c-b2c2-4862-b521-01d3bf69ab2b.png align="center")

By breaking down our CI/CD process into these stages, we ensure a systematic and automated approach to software development. This Jenkins pipeline, combined with Docker, provides a powerful foundation for building, testing, and deploying applications efficiently.