Lambda res handler

AWS Lambda APIG proxy integration helper to send an HTTP response.

- Installation
- API
- Usage
- Examples
- Publish

Installation

``
npm i @mooncake-dev/lambda-res-handler
`

API

The module exposes a function createResHandler that returns an resHandlers Object with helper methods to send HTTP responses. It can be configured with default headers, that will be sent every time the response handler helper is called.

$3

Parameters:

| Name | Required | Type | Description |
| -------------- | -------- | ------ | -------------------------------------------- |
| defaultHeaders | No | Object | Contains default headers as key-value pairs. |

Returns:

Object resHandlers.

This Object contains the following methods:

| Name | Description |
| ---- | ------------------------------------------------------------------- |
| json | Stringifies response payload as JSON. |
| html | Responds with html content and sets the proper content type headers |

#### resHandlers.json(code, body, headers)

Parameters:

| Name | Required | Type | Description |
| ------- | -------- | --------------- | ----------------------------------------------------------------------------- |
| code | No | Number | A valid HTTP status code, which defaults to 200. |
| body | No | Object or Array | The payload to be returned as JSON. |
| headers | No | Object | Any headers to send (in addition to the defaultHeaders) as key-value pairs. |

Returns:

Object.

This is an AWS Lambda conformant HTTP response Object:

`
{
headers: {},
statusCode: 200,
body: {}
}
`

Usage

`js
const createResHandler = require('@mooncake-dev/lambda-res-handler');
const sendRes = createResHandler();
sendRes.json(201, { hello: 'world' });
`

Examples

`js
'use strict';

const createResHandler = require('@mooncake-dev/lambda-res-handler');

const defaultHeaders = {
'Access-Control-Allow-Origin': '*'
};

const sendRes = createResHandler(defaultHeaders);

/**
* Lambda APIG proxy integration.
*
* @param {Object} event - HTTP input
*
* @return {Object} HTTP output
*/
module.exports.sendData = async event => {
try {
const data = [1, 2, 3];
return sendRes.json(200, data);
} catch (err) {
console.log('error: ', err); // eslint-disable-line no-console

const statusCode = err.statusCode || 500;
const data = {
error: err.message,
details: err.details
};

return sendRes.json(statusCode, data, { 'extra-header': 'kaput' });
}
};
`

#### resHandlers.html(code, body, headers)

Parameters:

| Name | Required | Type | Description |
| ------- | -------- | ------ | ----------------------------------------------------------------------------- |
| code | No | Number | A valid HTTP status code, which defaults to 200. |
| body | No | String | The payload to be returned as HTML. |
| headers | No | Object | Any headers to send (in addition to the defaultHeaders) as key-value pairs. |

NOTE:
_Content-Type header is always set as text/html._
_For working with this function you need to set the "Content-Type" API Gateway response headers to "text/html" as well, for the specific endpoint. Additionally you have to set a response template with value "$input.path('$')"._

Returns:

Object.

This is an AWS Lambda conformant HTTP response Object:

`
{
headers: {},
statusCode: 200,
body: '

`js
const createResHandler = require('@mooncake-dev/lambda-res-handler');
const sendRes = createResHandler();
sendRes.html(
200,
'

`js
'use strict';

const createResHandler = require('@mooncake-dev/lambda-res-handler');

const sendRes = createResHandler();

/**
* Lambda APIG proxy integration.
*
* @param {Object} event - HTTP input
*
* @return {Object} HTTP output
*/
module.exports.sendData = async event => {
try {
const message = 'Hello World';
const html =

const html =

return sendRes.json(statusCode, html, { 'extra-header': 'kaput' });
}
};
`

Publish

For now we publish manually using:

`
npm publish --access public
`

Make sure:

- You increment the npm version after you make code changes with npm version`.
- You're logged in.

More information can be found here.