CDK Lambda PnP Functions

This CDK library allows you to bundle and deploy your AWS Lambda functions from a Yarn PnP project. This project emphasizes using the PnP runtime inside the Lambda environment without single-file bundling.

Features

• Bundles yarn workspaces and their dependencies so that you can use Yarn PnP in AWS Lambda.
• Smaller node dependency file sizes due to PnP compression
• First-class support for yarn workspaces focus and yarn.BUILD
• CDK hotswap compatibility to speed up your inner loop
• Allows you to group related lambda handlers into fewer assets to reduce asset publishing time
• Bring-your-own typescript compiler (works with tsc, esbuild, and swc.)
• Supports cross-workspace module resolution
• Supports hard-to-bundle packages if yarn PnP supports them

Yarn Workspace Function

YarnWorkspaceFunction provides a basic lambda function from a yarn workspace. Your compiled code and dependencies are staged and trimmed down using yarn's workspace-tools plugin and yarn workspaces focus command.

const handler = new YarnWorkspaceFunction(scope, 'Handler', {
  // Specify the yarn workspace package name
  workspace: 'lambda',
  // Specify the workspace-relative file containing the lambda handler
  handler: 'dist/api.handler',
  // Optionally specify where to find the yarn project
  projectPath: optionalYarnProjectDir,
});

// Use your function in an API, for example
const httpApi = new apigatewayv2.HttpApi(scope, 'HttpApi', {
  defaultIntegration: new apigatewayv2_integrations.LambdaProxyIntegration({
    handler,
  }),
});

Excluding files

To exclude files from the lambda code bundle, add standard .npmignore files to your packages. It is generally recommended to include a .npmignore in the package that synthesizes your cdk.out cloud assembly to avoid bundling the cdk.out directory.

Example project structure:

.
├── package.json
├── ...
└── packages
    ├── api
    │   ├── package.json
    │   └── ...
    └── cdk
        ├── package.json
        ├── .npmignore
        ├── ...
        └── cdk.out <.npmignored>
            └── ... <.npmignored>

Use yarn.BUILD

The YarnBuildFunction construct provides a more robust out-of-the-box experience through the yarn.BUILD yarn plugin. In addition to bundling code from a yarn workspace, this construct allows you to run yarn.BUILD's build command during construct synthesis. This build command will automatically build your workspace and all workspace dependencies.

const handler = new YarnBuildFunction(scope, 'Handler', {
  // Specify the yarn workspace package name
  workspace: 'lambda',
  // Specify the workspace-relative path containing the lambda handler
  handler: 'dist/api.handler',
  // Optionally run 'yarn install'.
  runInstall: true,
  // Optionally run 'yarn workspace lambda build'.
  runBuild: true,
  // Optionally specify where to find the yarn project
  projectPath: optionalYarnProjectDir,
});

// Use your function in an API, for example
const httpApi = new apigatewayv2.HttpApi(scope, 'HttpApi', {
  defaultIntegration: new apigatewayv2_integrations.LambdaProxyIntegration({
    handler,
  }),
});