How to add proxy to Node / Express site?

Question

My site is running on Node and using the Express framework.

My goal is to gather data from the Yahoo Placefinder api. It does not support JSONP, so I need to send my JQuery.getJSON request to my own proxy. My proxy would then send an http request to the Placefinder api, and echo the response.

If I were using php instead of Node, I would just make a new php file that includes a curl request to the placefinder api and echo the response.

But, I am using Node and I'm not sure where to start.

And, I'm using the Express framework.

My Questions are:

1. Where would the proxy fit within the Express framework? The public folder?

2. Where can I find some info on how to code a proxy in Node?

3. Will I need to modify the configuration of my Rackspace cloud (ubuntu) server in order for this to be possible?

Answer 1

2. See node-http-proxy . It should be better than implementing your own proxy.

3. Express lets you add middlewares as arguments when you do express.createServer() . Or, you can add them afterwards by using .use(proxy) .

4. I don't think so.

To give an example (untested code):

var httpProxy = require('http-proxy'), express = require('express');
var yahooProxy = httpProxy.createServer(80, 'yahoo.com');
var app = express.createServer();
app.configure(function () {
    app.use('/yahoo', yahooProxy);
});

...

Answer 2

Here's another example with 1.0.X that demonstrates header injection.

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

app.configure(function() {

  // Inject some request headers here before we proxy...
  app.use( function( req, res, next ) {
    req.headers[ 'x-my-header' ] = 'blah blah';
    next();
  });

  // Proxy based on path...
  app.use( '/stack', proxy({ target: 'http://stackoverflow.com'} ).web );
  app.use( '/yahoo', proxy({ target: 'http://yahoo.com'} ).web );

  app.use( function( req, res ) {
    res.send({ ok: false, message: 'Not much here.' })
  });

}).listen( 3000 );

Answer 3

You can just add another route to your express app, perhaps at /api/yahoo/... .

This view function will then make a call to the Yahoo API, probably using: http://nodejs.org/docs/v0.4.9/api/http.html#http.request , and then when that request finishes you simple return the result as JSON.

However, keep in mind that your proxy is public and that anyone can make requests through it. I would suggest some basic authorization. A generated value which you provide to the page making the request should work.

Answer 4

Using http-proxy 1.0 with express:

var httpProxy = require('http-proxy');

var apiProxy = httProxy.createProxyServer();

app.get("/api/*", function(req, res){ 
  apiProxy.web(req, res, { target: 'http://google.com:80' });
});

Answer 5

Nowadays this seems to be the easiest solution to add a proxy to Express: https://www.npmjs.org/package/proxy-middleware