Create a simple pipeline using CodeCommit repository

As a follow up to the presentation, I would like to present a demo of a simple pipeline using CodeCommit repository.

We are going to use us-east-1 region for this demo.

Table of Contents

1. Create AWS CLI User
2. Create IAM Roles
3. Create a CodeCommit repository
4. Add sample code to your CodeCommit repository
5. Create an EC2 Linux instance and install the CodeDeploy agent
6. Create an application in CodeDeploy
7. Create a pipeline in CodePipeline
8. Modify code in your CodeCommit repository
9. Clean Up
10. Summary
11. Referrals

Step 1. Create AWS CLI User

1. Navigate to IAM > Users > Click Add users
2. Enter a User Name, Select Access key - Programmatic access and Click Next: Permissions
3. Select Administator at Add user to group and Click Next: Tags
4. Click Next: Review
5. Click Create user
6. Click Download.csv and Close
7. Again navigate to IAM > Users > Click on the user that was created in the previous step
8. Navigate to Security Credentials
9. Click on Generate Credentials under HTTPS Git credentials for AWS CodeCommit
10. Click Download credentials and Close
11. Setup AWS CLI as shown below.

Step 2. Create IAM Roles

We are going to create two IAM Roles: one for EC2 and the other one for Code Deploy

EC2InstanceRole

1. Navigate to IAM > click Roles > click Create role.
2. Select EC2 under Common use cases and click Next.
3. Search for and select the policy named AmazonEC2RoleforAWSCodeDeploy, and then click Next.
4. Enter a name for the role as EC2InstanceRole and then click Create role.

CodeDeployRole

1. Navigate to IAM > click Roles > click Create role.
2. Under Use cases for other AWS services: > Select CodeDeploy and click Next.
3. AWSCodeDeployRole managed policy will be automatically added, so click Next
4. Enter a name for the role as CodeDeployRole and then click Create role.

Step 3. Create a CodeCommit repository

1. Navigate to CodeCommit
2. On the Repositories page > click Create repository > Enter MyDemoRepo as Repository name and then click Create.
3. Copy the git clone command from Clone the repository and execute the following command

mkdir codedeploy
git clone https://git-codecommit.us-east-1.amazonaws.com/v1/repos/MyDemoRepo
Cloning into 'MyDemoRepo'...
warning: You appear to have cloned an empty repository.

Note: Enter git credentials when cloning the repo for the first time.

Step 4. Add sample code to your CodeCommit repository

1. We will clone github code to /tmp folder and then copy the contents to codecommit's MyDemoRepo
   

   mkdir -p /tmp;
   cd /tmp;
   git clone https://github.com/kasukur/codedeploy.git
   cp -rf codedeploy/MyDemoRepo/* ~/codedeploy/MyDemoRepo/.
   

2. Commit and push the files to CodeCommit MyDemoRepo repository
   

   cd MyDemoRepo
   git add -A
   git commit -m "Add sample application files"
   git push
   

Note: I have used the code from SampleApp_Linux.zip and Solid State HTML5 template. Alternatively, you can download both manually and add them to codecommit's MyDemoRepo

The repository tree should look like this:

MyDemoRepo
       │-- appspec.yml
       │-- index.html
       │-- LICENSE.txt
       └-- scripts
           │-- install_dependencies
           │-- start_server
           └-- stop_server

AppSpec file must be a YAML-formatted file named appspec.yml and it must be placed in the root of the directory structure of an application's source code, otherwise deployments fail. It is used by CodeDeploy to determine:
- What it should install onto your instances from your application revision in Amazon S3 or GitHub.
- Which lifecycle event hooks to run in response to deployment lifecycle events.

version: 0.0
os: linux
files:
  - source: /index.html
    destination: /var/www/html/
hooks:
  BeforeInstall:
    - location: scripts/install_dependencies
      timeout: 300
      runas: root
    - location: scripts/start_server
      timeout: 300
      runas: root
  ApplicationStop:
    - location: scripts/stop_server
      timeout: 300
      runas: root

Step 5. Create an EC2 Linux instance and install the CodeDeploy agent

We are going to create an EC2 instance, where we deploy a sample application using CodeDeploy agent.
We are also going to attach an IAM role EC2InstanceRole to the instance (known as an instance role) to allow it to fetch files that the CodeDeploy agent uses to deploy your application.

1. Navigate to EC2 > Instances > Click Launch Intances
2. Enter Name as MyCodePipelineDemo
3. Select Amazon Linux 2 AMI1 and Instance Type t2.micro Free tier eligible
4. You could create a key pair or choose Proceed without a key pair. Creating a key pair would allow you to logon to the EC2 instance and check the application.
5. Select Allow SSH traffic from My IP and Allow HTTP traffic from the internet
6. Click Advanced Details > Select EC2InstanceRole under IAM instance profile and enter the following in the user data and click Launch Instance

Note: New EC2 console adds a tag with key: Name and Value: MyCodePipelineDemo. In case you don't see the Tags, please add them under Tags section by selecting the EC2 instance in EC2 console.

#!/bin/bash
sudo yum -y update
sudo yum install -y ruby
sudo yum install -y aws-cli
sudo cd /home/ec2-user
sudo wget https://aws-codedeploy-us-east-2.s3.us-east-2.amazonaws.com/latest/install
sudo chmod +x ./install
sudo ./install auto

Note: the user data installs ruby, aws-cli and CodeDeploy agent

Step 6. Create an application in CodeDeploy

Create an application in CodeDeploy

1. Navigate to CodeDeploy > Applications.
2. In Application name, enter MyDemoApplication.
3. In Compute Platform, choose EC2/On-premises.
4. Choose Create application.

Create a deployment group in CodeDeploy
A deployment group is a resource that defines deployment-related settings like which instances to deploy to and how fast to deploy them.

1. On the page that displays your application, choose Create deployment group.
2. In Deployment group name, enter MyDemoDeploymentGroup.
3. In Service Role, choose the service role CodeDeployRole, which we created earlier.
4. Under Deployment type, choose In-place.
5. Under Environment configuration, choose Amazon EC2 Instances. In the Key field, enter Name. In the Value field, enter the MyCodePipelineDemo.
6. Under Deployment settings, choose CodeDeployDefault.OneAtaTime.
7. Under Load Balancer, make sure Enable load balancing is not selected. You do not need to set up a load balancer or choose a target group for this example.
8. Click Create deployment group.

Step 7. Create a pipeline in CodePipeline

We are now ready to create the pipeline.
In this step, we create a pipeline that runs automatically when code is pushed to your CodeCommit repository.

Create a CodePipeline pipeline

1. Navigate to Pipelines > click Create pipeline.
2. In Pipeline name, enter MyFirstPipeline.
3. In Service role, choose New service role to allow CodePipeline to create a service role in IAM and click Next
4. Select AWS CodeCommit in Source provider. Select MyDemoRepo in Repository name. Select master in Branch name. Select Amazon CloudWatch Events (recommended) under Change detection options. Select CodePipeline default under Output artifact format and click Next .
5. Click Skip build stage as we are deploying a static website.
6. Click skip at Your pipeline will not include a build stage. Are you sure you want to skip this stage?
7. At deploy stage, Select AWS CodeDeploy in Deploy provider, Select MyDemoApplication in Application name, Select MyDemoDeploymentGroup in Deployment group and then click Next .
8. Review the information and then click Create pipeline.

9. The pipeline starts running after it is created. It downloads the code from your CodeCommit repository and creates a CodeDeploy deployment to your EC2 instance. You can view progress and success and failure messages as the CodePipeline sample deploys the webpage to the Amazon EC2 instance in the CodeDeploy deployment.

   If Deploy fails with an error, one of the reasons could be that codedeploy-agent may not be running on the EC2 instance, which we can check by running the following command
   

   sudo service codedeploy-agent status
   The AWS CodeDeploy agent is running as PID 3436
   

10. Now the pipeline has succeeded but when we check index.html. it appears that the stylesheets...etc are missing
    Let's fix this by updating appspec.yml
    from: source: /index.html to source: /
    

    version: 0.0
    os: linux
    files:
    - source: /
        destination: /var/www/html/
    hooks:
    BeforeInstall:
        - location: scripts/install_dependencies
        timeout: 300
        runas: root
        - location: scripts/start_server
        timeout: 300
        runas: root
    ApplicationStop:
        - location: scripts/stop_server
        timeout: 300
        runas: root
    

    If source is a single slash ("/" for Amazon Linux, RHEL, and Ubuntu Server instances, or "\" for Windows Server instances), then all of the files from your revision are copied to the instance.

11. Commit and push the changes
    

    git add -A
    git commit -m "updated appspec.yml"
    git push
    

12. The pipeline will automatically pick up the changes and run the Deploy because of Amazon EventBridge Rule

Step 9

Step 10

Step 12

Step 8. Modify code in your CodeCommit repository

1. Update the following line of HTML code in index.html and push the changes. Change the value from: This is Solid State, to: This is Solid State - Version 1

2. Commit and push the changes
   

   git status
   git commit -am "updated index.html"
   git push
   

3. index.html got updated on our EC2 instance.
   

   grep -i version /var/www/html/index.html 
   <h2>This is Solid State - Version 1</h2>
   

Step 9. Clean Up

1. Terminate MyCodePipelineDemo EC2 Instance.
2. Delete MyFirstPipeline under Pipelines, which will remove Amazon CloudWatch Events rule related to the pipeline.
3. Delete MyDemoApplication under Applications.
4. Delete MyDemoRepo under CodeCommit > Repositories.
5. Empty and delete S3 bucket prefixed with codepipeline.

Summary

• In this demo, we learnt how easy it is to setup a simple pipeline using CodeCommit, CodeDeploy and Pipeline.

Referrals

• Tutorial: Create a simple pipeline (CodeCommit repository)
• Cover Image by @darya_jumelya from unsplash.