apollusehs-devops/aws-cross-account-cicd-git-actions

aws-cross-account-cicd-git-actions

This project is a simplistic implementation of Lambda backed REST api to be deployed via GitHub Action and CDK (Typescript)

License

This library is licensed under the MIT-0 License. See the LICENSE file.

System requirements

• node (version >= 12x)
• jq

Prerequisites

Before proceeding further please read and README.md in aws-cross-account-cicd-git-actions-prereq and carry out the deployment steps specified.

How to get started

Before you checkin the code in this repo into your own git repo, you will need to make updates as shown below. Replace the <target-account-id> in parameter CFN_EXECUTION_ROLE in src/params/cdk_stack_param.json file with AWS account id of your designated deployment target account. This parameter represets the iam role that would be assumed by CDK to carryout deployment. You may get the full value of parameter CFN_EXECUTION_ROLE from Cloudformation output export GIT-ACTIONS-CF-EXECUTION-ROLE-ARN of stack deployed in Prerequisite.

Project Structure

Project has been structured such that the API stack has its own folder under root folder src/

src/git-action-demo-api-stack deploys AWS resources associated with Git Action Demo API. src/params/cdk_stack_param.json parameter file

Stack specific folder has following components

• /lambda folder which holds individual lambda functions implemented as part of the API.
• cdk_stack.ts representing CDK stack for Lambda, API Gateway and associated resources

The stack ties into app.ts at root folder location which represents CDK app.

Deployment using CDK

The project is to be deployed as a whole app using GitAction workflows defined under .github/workflows folder. Each workflow has its own .yml file whose name is in the format cicd-workflow-<region>.yml. The single workflow handles deployment to a specific region that is mentioned in its name. For e.g. cicd-workflow-us-east-1 deploys to us-east-1 region.

Workflow has following set of steps.

1. Workflow is triggered when code is pushed to a specific branch in the repo.
2. Checks out latest version of code.
3. Configures AWS credentials using Tools Account Access Key and Secret to assume the Cross Account Role for deployment.
4. Installs prerequisits such as CDK
5. Builds and deploys cdk stacks using deploy.sh script provided at the root of the project folder.

The deploy.sh script takes following deployment steps

1. Install npm packages.
2. Transpile code into javascript in dist folder.
3. Package .js files into zip
4. Uses CDK CLI commands to first bootstrap CDK app and then deploy it. To manually deploy using script directly, we need to set up default profile for TARGET aws account and then run deploy.sh.