travix-acl-middleware

Express middleware for ACL to be used in all Express servers used by Travix.

Usage & Examples

Configuring the ACL middleware

import express from 'express';
import acl from 'acl';

const app = express();
app.use(acl({
  configure(context) {
    // allow health check endpoint to be accessible only from localhost
    context.forResource('/health_check')
           .deny('*')
           .allow('127.0.0.1/32');

    // allow protected resources to be accessible only from the internal network (192.168.0.*)
    // and let '/protected/resource/1' to be accessible by a few external ips
    context.forResource('/protected/resource/1')
           .forResource('/protected/resource/2')
           .deny('*')
           .allow('192.168.0.1/24')
           .forResource('/protected/resource/1')
           .allow('104.16.35.24/29');


    // blacklisting bad ip from accessing home page
    var BAD_IP = '123.456.789.001/32';
    context.forResource('/')
           .allow('*')
           .deny(BAD_IP);
  }
}));

Note: express-style path strings are also supported, see path-to-regexp repository for more info.

Redefine Http Status code returned

By default, any blocked requests will return status code 403 FORBIDDEN. You can redefine it using the options.respondWith property. For instance:

app.use(acl({
  configure() {
    ...
  },
  respondWith: 404
}));

This will respond with a 404 NOT FOUND status instead.

app.use(acl({
  configure() {
    ...
  },
  respondWith(req) {
    if (req.path === '/health_check') {
      return 404;
    }
    return 400;
  }
}))

This will respond with a 404 NOT FOUND status for the health check endpoint, but return 400 BAD REQUEST for all other blocked requests.

Custom Response

If you prefer, you can handle the response yourself by providing a handleResponse function:

app.use(acl({
  configure() {
    ...
  },
  handleResponse(res, statusCode) {
     res.status(statusCode)
        .send("We're sorry, you don't have access to the page you requested. Please go back to the homepage");
  }
}));