Kolp

"jetpack for building microservice on Lambda"

Accronym for Koa on Lambda (Pack). A tiny library toolbox for Lambda (using Koa, Koa Router) then describe your endpoints with controllers.

Version 2:

• Updated npm package dependencies to use aws-sdk v3 instead.

Install

npm i --save kolp

# OR

yarn kolp

NOTE we listed koa as our peerDependencies so please include the koa in your own codebase.

Usage

Start your typescript Lambda project. Describe your endpoints with Controller style.

To expose each method as routes. Use our built-in decorator. Route which accepts method, paths, and Koa's middlwares.

controllers/hello.cotnroller.ts

import type { Context } from 'koa'
import { Route, BaseRoutedController } from 'kolp'

export class HelloController extends BaseRoutedController {

  @Route('post', '/echo')
  async migrate(context: Context) {
    return context.request
  }

  @Route()
  async index(context: Context) {
    return {
      hello: 'world'
    }
  }
}

Or you can describe your controllers in a classical way. (Avoid using decorators). This method introduce less code when it is bundled.

controllers/hello.controller.ts

import type { Context } from 'koa'
import { RouteMap, BaseRoutedController } from 'kolp'

export class HelloController extends BasedRouteController {

  public getRouteMaps(): RouteMap {
    return {
      ...super.getRouteMaps(),
      index: { method: 'get', path: '/', middlewares: [] }, // Same as our decorator above.
    }
  }

  async index(context: Context) {
    return {
      hello: 'world'
    }
  }
}

Now to use these controllers. You will need to map them to paths in the Lambda's handler. Instead of creating your own handler from scratch. Just use makeServerWithRouter method to create your handler function.

The function itself allow you to customize the created router (Root router). Here is the example.

handler.ts

import 'source-map-support/register'
import { makeServerWithRouter, withJson } from 'kolp'

import { HelloController } from './controllers/hello.controller'

export default makeServerWithRouter((router) => {
  router.prefix('/hello')
    .use(withJson())    // Json error handler!
  
  // Register your controllers here.
  new HelloController().register('/hi', router)
})

By the example above. You will be able to:

curl -XGET http://localhost:9000/hello/hi

TODO

[ ] Example repo
[ ] Inter Service Communication
[X] SNS/SQS Handler