nice-lambda

A nice way to make AWS Lambda functions and call them

wrapper methods

lambda(logicHandler: (call: LambdaCall) => Promise | any)

Returns an event handler function for use with AWS Lambda. The logicHandler function provided is the handler implementation and may be async. logicHandler receives a single object argument which contains the Lambda event and context objects. It is expected to return or resolve to a value which will be used as the successful result of the Lambda callback. Any error that is thrown will be caught and returned as the error result of the Lambda callback instead.

Example:

const { lambda } = require('nice-lambda');

module.exports.handler = lambda(
	async ({ event }) => {
		console.log(`Lambda event: ${JSON.stringify(event)}`);
		// [... await some data stuff ...]
		return 23;
	},
);

api(logicHandler: (call: LambdaCall) => Promise | any)

Similar to lambda but converts everything into API Gateway responses. If a data response contains a statusCode property, the API response will use it as the status code and use data.body as the API response body; otherwise the status code will default to 200 and the entire data response will be used as the API response body. If an error is an instance of Boom, the API response will use its status code and error message; otherwise the status code will default to 500 and a generic server error message will be used. If the body (data or data.body, depending) is a string, it will be returned as-is; otherwise it will be JSON-stringified before return.

Examples:

const { api } = require('nice-lambda');
const { User } = require('./model');

module.exports.handler = api(
	async ({ event }) => {
		const user = await User.findById(event.pathParameters.userId);
		const posts = await User.getPosts();
		return { // response in JSON:API format: https://jsonapi.org/
			data: {
				user,
				posts,
			},
			meta: {
				authors: ['Joe Lafiosca'],
			},
		};
	},
);

const { api } = require('nice-lambda');
const Boom = require('@hapi/boom');

module.exports.handler = api(() => {
	throw Boom.forbidden('Special permission required');
});

postFormUrlEncoded(logicHandler: (call: LambdaCall) => Promise | any)

Preprocesses an event.body64 base64-encoded form-url-encoded input into an event.body object before running logicHandler. Returns the raw response from logicHandler.

postRaw(logicHandler: (call: LambdaCall) => Promise | any)

Preprocesses an event.body64 base64-encoded raw post input into an event.body object before running logicHandler. Returns the raw response from logicHandler.

apiMethods(methodMapping: { [key: string]: LogicHandler; })

Similar to api but creates a multi-purpose Lambda which can handle the specified HTTP methods. methodMapping should be an object in which the keys are lowercase HTTP method verbs (e.g., get) and their values are logic handlers like the ones you would pass to api.

const { apiMethods } = require('nice-lambda');
const {
	getResource,
	updateResource,
	deleteResource,
} = require('./resource');

exports.handler = apiMethods({
	get: getResource,
	post: updateResource,
	delete: deleteResource,
});

documentation note

The above documentation is incomplete, but further information can be found by examining the code.