Day 52: Your CI/CD Pipeline on AWS - Part 3 🚀☁

Welcome to Part 3 of your CI/CD pipeline journey on AWS! So far, you’ve explored CodeCommit for version control and CodeBuild for automating builds. Today, we dive into AWS CodeDeploy, the tool that ensures smooth, automated application deployments across various environments. Let’s get started!

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What is AWS CodeDeploy?

AWS CodeDeploy automates application deployments to:

• Amazon EC2 instances

• On-premises servers

• Serverless Lambda functions

• Amazon ECS services

It supports deploying code stored in:

• Amazon S3 buckets

• CodeCommit repositories

• Third-party repositories (e.g., GitHub, Bitbucket)

With CodeDeploy, you don’t need to modify your existing code. It’s designed to handle deployments reliably with rollback and tracking capabilities.

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Tasks for Today

Task 01: Learn About appspec.yml and Deploy to EC2

Requirements:

• An Amazon EC2 instance with Nginx installed.

• A CodeDeploy IAM role with permissions to deploy applications.

• CodeDeploy agent installed on the EC2 instance.

Steps:

1. Understand the appspec.yml File:

   • This file defines how AWS CodeDeploy should deploy your application.

   • Key sections:

     • Resources: Files and scripts to deploy.

     • Hooks: Commands to execute at specific deployment stages (e.g., BeforeInstall, AfterInstall).

   • Example appspec.yml:

       version: 0.0
       os: linux
       files:
         - source: /
           destination: /usr/share/nginx/html
       hooks:
         AfterInstall:
           - location: scripts/restart-nginx.sh
             timeout: 300
             runas: root
     

2. Set Up CodeDeploy Agent on EC2:

   • SSH into your EC2 instance:

       ssh -i your-key.pem ec2-user@your-ec2-public-ip
     

   • Install the CodeDeploy agent:

       sudo apt-get update -y
       sudo apt-get install -y ruby wget
       cd /home/ec2-user
       wget https://aws-codedeploy-us-east-1.s3.amazonaws.com/latest/install
       sudo chmod +x ./install
       sudo ./install auto
       sudo service codedeploy-agent start
     

   • Verify the agent is running:

       sudo service codedeploy-agent status
     

3. Deploy index.html with Nginx:

   • Ensure your EC2 instance is ready to serve files using Nginx.

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Task 02: Add appspec.yml and Deploy Application

Steps:

1. Create the appspec.yml File:

   • Add an appspec.yml file to your CodeCommit repository:

       version: 0.0
       os: linux
       files:
         - source: /
           destination: /usr/share/nginx/html
       hooks:
         AfterInstall:
           - location: scripts/restart-nginx.sh
             timeout: 300
             runas: root
     

2. Add a Restart Script:

   • Create a script to restart Nginx and add it to the repository (scripts/restart-nginx.sh):

       #!/bin/bash
       sudo systemctl restart nginx
     

3. Push Changes to CodeCommit:

    git add appspec.yml scripts/restart-nginx.sh
    git commit -m "Added appspec.yml and restart script"
    git push origin main
   

4. Create a Deployment Group in CodeDeploy:

   • Go to AWS CodeDeploy in the AWS Management Console.

   • Create an Application and a Deployment Group.

   • Select your EC2 instance and associate it with the deployment group.

5. Run the Deployment:

   • Start a deployment using the CodeCommit repository and appspec.yml.

   • Monitor the deployment in the CodeDeploy console.

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Key Takeaways

• CodeDeploy simplifies deploying applications to various environments with zero manual effort.

• The appspec.yml file is crucial for defining deployment steps and hooks.

• Installing the CodeDeploy agent on EC2 is necessary for deployments.

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Stay tuned for Part 4, where we’ll bring everything together with AWS CodePipeline!