Forward express js route to other server

Question

I'm writing an express.js app and would like to serve certain routes from another server.

Express serves some routes starting with api.example.com/v1/*. I would like any paths starting with /ad/hoc/ to be forwarded to another server and the response served by Express, e.g. api.example.com/ad/hoc/endpoint.php would be piped to grampas-lamp-stack.example.com/ad/hoc/endpoint.php.

I can accomplish this with res.redirect but I'd like to stream the response through my Express app and avoid redirecting the browser to another IP address.

app.js

var express = require('express');
var app = express();

app.get('/v1/users/:id', UserCtrl.get);
app.get('/v1/users/search', UserCtrl.search);

app.get('/ad/hoc/*', function(req, res) {
  res.redirect('http://grampas-lamp-stack.example.com' + req.url);
}

I tried searching "proxy requests express" but I'm not sure if proxy is an accurate term for what I'm doing. If there's a better word for this topic or what I'm trying to accomplish, please let me know.

Answer 1

You can use express-http-proxy.

And yes, proxying is the accurate term for what you are looking for. It will underneath forward the request to another url, as the API will also imply.

Here's an example usage:

var proxy = require('express-http-proxy');
var app = require('express')();

app.use('/route/you/want/proxied', proxy('proxyHostHere', {
    forwardPath: function (req, res) {
      return '/path/where/you/want/to/proxy/' + req.url
    }
}))