NodeJS - Reverse Proxy with Route Changing - node.js

Question

I'm currently using NodeJS/Express as a simple domain router running on my VPS on port 80. My routes.coffee looks something like this:
request = require("request")
module.exports = (app) ->
#404, 503, error
app.get "/404", (req, res, next) ->
res.send "404. Sowway. :("
app.get "/error", (req, res, next) ->
res.send "STOP SENDING ERRORS! It ain't cool, yo."
#Domain Redirects
app.all '/*', (req, res, next) ->
hostname = req.headers.host.split(":")[0]
#Website1.com
if hostname == 'website1.com'
res.status 301
res.redirect 'http://facebook.com/website1'
#Example2.com
else if hostname == 'example2.com'
pathToGo = (req.url).replace('www.','').replace('http://example2.com','')
request('http://localhost:8020'+pathToGo).pipe(res)
#Other
else
res.redirect '/404'
As you can see in Example2.com, I'm attempting to reverse proxy to another node instance on a different port. Overall it works perfectly, except for one issue. If the route on the other node instance changes (Redirects from example2.com/page1.html to example2.com/post5), the URL in the address bar doesn't change. Would anyone happen to have a nice workaround for this? Or maybe a better way to reverse proxy? Thanks!

Answer 1

In order to redirect the client, you should set the http-status-code to 3xx and send a location header.
I'm not familiar with request module but I believe it follows redirects by default.
On the other hand, you're piping the proxy-request's response to client's response object, discarding the headers and the status code. That's why the clients don't get redirected.
Here is a simple reverse HTTP proxy using the built-in HTTP client. It's written in javascript but you can easily translate it to coffeescript and use request module if you want.
var http = require('http');
var url = require('url');
var server = http.createServer(function (req, res) {
parsedUrl = url.parse(req.url);
var headersCopy = {};
// create a copy of request headers
for (attr in req.headers) {
if (!req.headers.hasOwnProperty(attr)) continue;
headersCopy[attr] = req.headers[attr];
}
// set request host header
if (headersCopy.host) headersCopy.host = 'localhost:8020';
var options = {
host: 'localhost:8020',
method: req.method,
path: parsedUrl.path,
headers: headersCopy
};
var clientRequest = http.request(options);
clientRequest.on('response', function (clientResponse) {
res.statusCode = clientResponse.statusCode;
for (header in clientResponse.headers) {
if (!clientResponse.headers.hasOwnProperty(header)) continue;
res.setHeader(header, clientResponse.headers[header]);
}
clientResponse.pipe(res);
});
req.pipe(clientRequest);
});
server.listen(80);
// drop root privileges
server.on('listening', function () {
process.setgid && process.setgid('nobody');
process.setuid && process.setuid('nobody');
});