Typescript AWS CDK Generator: aws-cdk-gen

This project allows you to generate Typescript constructs for a variety of common AWS CDK use cases. It was built using PlopJS.

Why?

The hope is that you will be able to use this tool to remove boilerplate code and get 90% of the code needed with a few key strokes.

Additionally, new developers can learn how to connect CDK constructs in a project with minimum changes.

Library In Action

Here is an example of generating a Go Lambda.

Here is an example of the outputted files.

As you can see it generates the Lambda construct, a Lambda integration, and a directory that contains a Go program as well as a build script. This gives a developer all they need to get started.

Caveats

This tool has a few caveats.

1. This tool is opinionated in the sense that it generates files at set paths.

2. This initial version is based on aws-cdk version 1.85.0. As a result, it may not work with older CDK projects.

3. There are a number of experimental constructs used in this package that are not in active development. As a result, some of the construct's may not work in the future. I plan on moving to more stable constructs in future releases.

4. The user needs to install any missing dependencies.

Installation

npm install --save-dev aws-cdk-gen

Getting started

Create a script in your package.json to generate CDK constructs. For example

"scripts": {
    "aws-cdk-gen": "aws-cdk-gen"
}

Run your script and that's it!

Base Generators Available

There a few constructs available upon starting the tool in a new CDK project. Below is a screenshot of the initial options available.

Here are a description of the various options.

• Go Lambda - Generate a Go Lambda with an example handler. You need to build the Go artifact to successfully deploy. Please follow the README in the generated handler files. Uses experimental construct.

  • Inputs:
    • Lambda Name
  • Outputs:
    • S3 Asset
    • Standard Lambda Function
    • Api Gateway V2 Lambda Integration
    • example Go main file
    • README on build process
    • shell script to automate build

• NodeJS Lambda - Generate a NodeJS Lambda with an example handler. Uses experimental construct.

  • Inputs:
    • Lambda Name
  • Outputs:
    • NodeJS Experimental Lambda Function
    • Api Gateway V2 Lambda Integration
    • example JS handler

• S3 Bucket - Basic S3 Bucket construct.

  • Inputs:
    • Bucket Name
  • Outputs:
    • S3 Bucket Construct

• API Gateway - Generate an API Gateway. Needed to add a Lambda Route or generate a DynamoDb stack.

  • Inputs:
    • Api Gateway Name
  • Outputs:
    • Api GatewayV2 Construct

Note: The comments in the generated API Gateway construct file are used to inject code. It is not recommended to delete them.

Generators Available With Dependencies

There are a few generators that are dependent on other constructs to have been generated. As a result, they are initially hidden from the user.

Below is a screenshot of the hidden options available.

Here are a description of the various options.

• Add Lambda Route - Generate a route for a Lambda to an existing API Gateway. Requires the creation of both a Lambda and an API Gateway to see the options.

  • Inputs:
    • Select API GatewayV2 - select from list of previously generated gateways.
    • Select API GatewayV2 Lambda Integration - select from list of previously generated lambda integrations.
    • Define Route for Lambda - enter string for route. Ex. "/users/".
  • Outputs:
    • Imports Lambda Integration into Api Gateway construct. Adds a route for the Lambda to the Gateway.

• DynamoDB and Lambdas - Generate a DynamoDB table and 4 Lambdas with example handlers. The handlers cover GET, POST, PUT, and DELETE. You will need to configure a data schema to properly use this function. Requires the creation of an API Gateway to see the option.

  • Inputs:
    • Select API GatewayV2 - select from list of previously generated gateways.
    • Name your Table - Enter string for your table.
    • Select a name for your Lambdas - Enter string for Lambdas. Will be used for all 4 Lambdas.
    • Define Route for Lambdas - enter string for route. Ex. "/users/". Will be used for all 4 Lambdas.
  • Outputs:
    • Will have one main DynamoDB construct. It contains:
      • 1 DynamoDB Table
      • 4 NodeJS Lambdas granted access to the table and passed the table name as environment variable
      • 4 LambdaProxy Integrations
    • Will output a handler folder with 4 different JS handler files.
    • Will add 4 routes to the API Gateway that you selected.

License

Licensed under MIT

Copyright (c) 2021 Jayson Alzate