Introducing CDK TypeScript resource
Why?
All-TypeScript codebase including infrastructure as a code with CDK and application code is a pleasure to use. Deployment of it, not so much.
You can transpile your code to a new directory, copy package.json there, install production dependencies, and then have CDK send that whole folder to lambda. It's painful to set up, and it will bring a ton of unnecessary code (everything in node_modules) along. Webpack is better - it can take an entry point and create a small bundled file that includes only what you need. Unfortunately, no one likes to set up complex and diverging webpack configurations, especially in a monorepo with tens if not hundreds of tiny packages.
What?
We wanted the TypeScript Lambda experience to be seamless - if a developer wants to create a new function, he should create a typescript file, add it to CDK and that's it. Now you can do it like so:
import { TypeScriptFunction } from "cdk-typescript-tooling";
// ...
const statusHandle = new TypeScriptFunction(scope, "Purchase-Status-Endpoint", {
entry: require.resolve("@sales/purchase-endpoint/src/handler.ts"),
});It takes all the parameters that you know from @aws-cdk/aws-lambda, like runtime, environment, timeout, and so on, because we extend it.
Expose easily through HTTP
Why?
In our development exposing lambdas through http is a very frequent case. The code around it for most cases stays exactly the same and increases the noise. We define the function:
const handler = new TypeScriptFunction(stack, "Add-Function", {
entry: require.resolve("@calculator/add/src/handler.ts"),
});Add HttpApi using LambdaProxyIntegration
const statusApi = new apiGateway2.HttpApi(stack, "PurchaseStatusHttpApi", {
defaultIntegration: new apiGateway2Integrations.LambdaProxyIntegration({
handler,
}),
});Add the url to CfnOutput to, among others, see the url in CI/CD logs.
new CfnOutput(stack, "addUrl", {
value: statusApi.url,
});What?
Define your function with withHttp option like so:
new TypeScriptFunction(stack, "Add-Function", {
entry: require.resolve("@calculator/add/src/handler.ts"),
withHttp: true,
});...and the other two steps will be done for you automatically.
You can watch me build an example using the TypeScriptFunction from cdk-typescript-tooling here:
The code source created while recording that video is here
Let me know if you have any questions or thoughts in the comments below.