magiclambda v0.1.1

MagicLambda 🪄λ

A simple framework for building AWS Lambda functions that can handle multiple AWS API Gateway requests.

Installation

Install by npm

npm install --save magiclambda

Modify your tsconfig.json to enable annotations

{
  "compilerOptions": {
    "experimentalDecorators": true,
    "emitDecoratorMetadata": true
  }
}

Getting started

To have the MagicLambda handle API Gateway requests you will need to declare a Controller class with route handler methods.

// controller.ts

import { Controller, Get, PathParam, ok } from 'magiclambda'

@Controller('/example')
export class ExampleController {
  @Get('/hello/{name}')
  getHelloName (@PathParam('name') name: string): Response {
    return ok(`Hello ${name}`)
  }
}

Then you can use controllerHandler from monorepo library to automaticly create API Gateway compatible request handler, which will be able to handle all the requests defined in your controller.

// index.ts

import { controllerHandler } from 'magiclambda'
import { ExampleController } from './controller'

export const handler = controllerHandler(ExampleController)

Supported annotations

@Controller(basePath: string) class

Marks the annotated class as a Controller and assigns a basePath to all routes that it has defined.

@Get(path: string) method

Registers the annotated method as GET request handler for given path. Path params should be specified in {paramName} format.

@Post(path: string) method

Registers the annotated method as POST request handler for given path. Path params should be specified in {paramName} format.

@Put(path: string) method

Registers the annotated method as PUT request handler for given path. Path params should be specified in {paramName} format.

@Patch(path: string) method

Registers the annotated method as PATCH request handler for given path. Path params should be specified in {paramName} format.

@Delete(path: string) method

Registers the annotated method as DELETE request handler for given path. Path params should be specified in {paramName} format.

@PathParam(name: string) argument

Marks the annotated argument as the receiver of the path param name which was specified in the path of the Router

@QueryParam(name: string, required: boolean) argument

Marks the annotated argument as the receiver of the query param name. Setting required to true instructs the handler to fail the request if the query parameter is not present.

@RequestBody(required: boolean) argument

Marks the annotated argument as the receiver of the HTTP request body. Setting required to true instructs the handler to fail the request if the request body is not present.

@Validated (schema: Joi.Schema) argument

Instructs the handler to validate the annotated parameter (Path, Query or RequestBody) against given Joi schema.

Router response

MagicLambda provides utilities to make it easy to return a response body with common status codes. Simply return one of the following function results from your routers.

ok(body?: any)

Builds response with status code 200 and response body if provided

badRequest(body?: any)

Builds response with status code 400 and response body if provided

notFound(body?: any)

Builds response with status code 404 and response body if provided

internalServerError(body?: any)

Builds response with status code 500 and response body if provided

response(status: number, body?: any)

Builds response with status code status and response body if provided