hdemon/sam-local-dev-skeleton

sam-local-dev-skeleton

Install

By following this guide, install the AWS CLI and the AWS SAM CLI. And then,

npm install

Develop

Lambda

./scripts/start-api-on-local

DynamoDB

docker-compose up

GUI for DynamoDB

./scripts/start-dynamodb-admin

Deploy

sam build
sam deploy --guided

Use the SAM CLI to build and test locally

Test a single function by invoking it directly with a test event. An event is a JSON document that represents the input that the function receives from the event source. Test events are included in the events folder in this project.

Run functions locally and invoke them with the sam local invoke command.

sam local invoke HelloWorldFunction --event events/event.json

The SAM CLI can also emulate your application's API. Use the sam local start-api to run the API locally on port 3000.

sam local start-api
curl http://localhost:3000/

The SAM CLI reads the application template to determine the API's routes and the functions that they invoke. The Events property on each function's definition includes the route and method for each path.

      Events:
        HelloWorld:
          Type: Api
          Properties:
            Path: /hello
            Method: get

Add a resource to your application

The application template uses AWS Serverless Application Model (AWS SAM) to define application resources. AWS SAM is an extension of AWS CloudFormation with a simpler syntax for configuring common serverless application resources such as functions, triggers, and APIs. For resources not included in the SAM specification, you can use standard AWS CloudFormation resource types.

Fetch, tail, and filter Lambda function logs

To simplify troubleshooting, SAM CLI has a command called sam logs. sam logs lets you fetch logs generated by your deployed Lambda function from the command line. In addition to printing the logs on the terminal, this command has several nifty features to help you quickly find the bug.

NOTE: This command works for all AWS Lambda functions; not just the ones you deploy using SAM.

sam-local-dev-skeleton$ sam logs -n HelloWorldFunction --stack-name sam-local-dev-skeleton --tail

You can find more information and examples about filtering Lambda function logs in the SAM CLI Documentation.

Unit tests

Tests are defined in the hello-world/tests folder in this project. Use NPM to install the Mocha test framework and run unit tests.

sam-local-dev-skeleton$ cd hello-world
hello-world$ npm install
hello-world$ npm run test

Cleanup

To delete the sample application that you created, use the AWS CLI. Assuming you used your project name for the stack name, you can run the following:

aws cloudformation delete-stack --stack-name sam-local-dev-skeleton

Resources

See the AWS SAM developer guide for an introduction to SAM specification, the SAM CLI, and serverless application concepts.

Next, you can use AWS Serverless Application Repository to deploy ready to use Apps that go beyond hello world samples and learn how authors developed their applications: AWS Serverless Application Repository main page