README.md

Middy caching headers middleware

Caching headers middleware for the middy framework, the stylish Node.js middleware engine for AWS Lambda

This middleware sets HTTP caching headers, necessary for making the requests cache'able both in browsers and reverse proxies.

Sets headers in after and onError phases.

Install

To install this middleware you can use NPM:

npm install --save @schibsted/middy-caching-headers

Options

• success (object) - configuration for the successful requests
• errors (object) - configuration for the error requests based on the statusCode

Every section of the config contains 3 properties:

• directive (string, optional) - response directive e.g. must-revalidate, public etc.
• clientTime (int) - time to set max-age for
• serverTime (int) - time to set s-maxage for

See the sample usage below.

Sample usage

const middy = require('@middy/core');
const cors = require('@schibsted/middy-caching-headers');

const handler = middy(async () => ({
        statusCode: 200,
        body: JSON.stringify({ foo: 'bar' }),
    }));

handler
  .use(cors({
        success: {
            directive: null,
            serverTime: 3600,
            clientTime: 600,
        },
        errors: {
            default: {
                directive: null,
                serverTime: 5,
                clientTime: 5,
            },
            502: false,
            404: {
                directive: null,
                serverTime: 600,
                clientTime: 600,
            },
        },
    }));

// when Lambda runs the handler...
handler({}, {}, (_, response) => {
  expect(response).toEqual({
    statusCode: 200,
    headers:  {
        'cache-control': 'max-age=600,s-maxage=3600',
        'surrogate-control': 'max-age=3600',
    },
    body: JSON.stringify({ foo: 'bar' }),
  })
})

Contributing

Everyone is very welcome to contribute to this repository. Feel free to raise issues or to submit Pull Requests.