Serverless CI/CD Tutorial

Building, testing, and deploying Serverless apps using CodeBuild and CodePipeline

This repo is the demo code for a three-part tutorial on managing unit testing, integration testing, and deployment of apps built using the Serverless framework.

To play with this code locally, clone this repo and do the following:

1. Install global npm modules

npm install -g serverless eslint jest

2. Install local npm modules

Navigate to the app directory, and run

npm install

3. Bring up the DB

sls dynamodb install --stage dev
sls dynamodb start --stage dev
sls dynamodb migrate --stage dev

This series of commands installs a local DynamoDB, starts it, and creates any tables specified in the serverless.yml. Check your shell at http://localhost:8000/shell/ to interact with the db and view the created table.

4. Start the offline app

sls offline start --stage dev

The app is now available at http://localhost:3000.

The app has two endpoints:

GET /todos

Returns a list of todos:

[
    {
        "id": "9b3c415f-ceaa-49e3-b5af-0e335bfd4635",
        "completed": false,
        "title": "do things!",
        "updatedAt": 1513817875660
    }
]

POST /todos

Accepts an object in this format:

{
	"title": "do things!",
	"completed": false
}

Returns a status of 200. The created object is not returned; you can see it with a GET /todos.

5. Run Tests

To run unit tests, use

npm test

To lint, use

npm run-script lint

To run integration tests, use

npm run-script integration

6. Make Changes

If you change the serverless.yml file, you'll need to restart your local app:

• Stop the offline app; ctrl-c in the terminal where it's running is all you need. It's fine to leave the db running.
• Uncomment the line in the serverless.yml file that says noStart: true. This will prevent serverless offline from trying to start a new database.
• Run sls offline start --stage dev again.

Changes to any other file in the app (e.g. a handler) will be reflected immediately, and don't require a restart.