node-http-proxy is an HTTP programmable proxying library that supports
websockets. It is suitable for implementing components such as reverse
proxies and load balancers.
- Installation
- Upgrading from 0.8.x ?
- Core Concept
- Use Cases
- Options
- Listening for proxy events
- Shutdown
- Miscellaneous
- Contributing and Issues
- License
npm install http-proxy --save
Click here
A new proxy is created by calling createProxyServer and passing
an options object as argument (valid properties are available here)
var httpProxy = require('http-proxy');
var proxy = httpProxy.createProxyServer(options); // See (†)†Unless listen(..) is invoked on the object, this does not create a webserver. See below.
An object will be returned with four methods:
- web
req, res, [options](used for proxying regular HTTP(S) requests) - ws
req, socket, head, [options](used for proxying WS(S) requests) - listen
port(a function that wraps the object in a webserver, for your convenience) - close
[callback](a function that closes the inner webserver and stops listening on given port)
It is then possible to proxy requests by calling these functions
http.createServer(function(req, res) {
proxy.web(req, res, { target: 'http://mytarget.com:8080' });
});Errors can be listened on either using the Event Emitter API
proxy.on('error', function(e) {
...
});or using the callback API
proxy.web(req, res, { target: 'http://mytarget.com:8080' }, function(e) { ... });When a request is proxied it follows two different pipelines (available here)
which apply transformations to both the req and res object.
The first pipeline (incoming) is responsible for the creation and manipulation of the stream that connects your client to the target.
The second pipeline (outgoing) is responsible for the creation and manipulation of the stream that, from your target, returns data
to the client.
var http = require('http'),
httpProxy = require('http-proxy');
//
// Create your proxy server and set the target in the options.
//
httpProxy.createProxyServer({target:'http://localhost:9000'}).listen(8000); // See (†)
//
// Create your target server
//
http.createServer(function (req, res) {
res.writeHead(200, { 'Content-Type': 'text/plain' });
res.write('request successfully proxied!' + '\n' + JSON.stringify(req.headers, true, 2))
8000
;
res.end();
}).listen(9000);†Invoking listen(..) triggers the creation of a web server. Otherwise, just the proxy instance is created.
This example show how you can proxy a request using your own HTTP server and also you can put your own logic to handle the request.
var http = require('http'),
httpProxy = require('http-proxy');
//
// Create a proxy server with custom application logic
//
var proxy = httpProxy.createProxyServer({});
//
// Create your custom server and just call `proxy.web()` to proxy
// a web request to the target passed in the options
// also you can use `proxy.ws()` to proxy a websockets request
//
var server = http.createServer(function(req, res) {
// You can define here your custom logic to handle the request
// and then proxy the request.
proxy.web(req, res, { target: 'http://127.0.0.1:5060' });
});
console.log("listening on port 5050")
server.listen(5050);This example shows how you can proxy a request using your own HTTP server that modifies the outgoing proxy request by adding a special header.
var http = require('http'),
httpProxy = require('http-proxy');
//
// Create a proxy server with custom application logic
//
var proxy = httpProxy.createProxyServer({});
// To modify the proxy connection before data is sent, you can listen
// for the 'proxyReq' event. When the event is fired, you will receive
// the following arguments:
// (http.ClientRequest proxyReq, http.IncomingMessage req,
// http.ServerResponse res, Object options). This mechanism is useful when
// you need to modify the proxy request before the proxy connection
// is made to the target.
//
proxy.on('proxyReq', function(proxyReq, req, res, options) {
proxyReq.setHeader('X-Special-Proxy-Header', 'foobar');
});
var server = http.createServer(function(req, res) {
// You can define here your custom logic to handle the request
// and then proxy the request.
proxy.web(req, res, {
target: 'http://127.0.0.1:5060'
});
});
console.log("listening on port 5050")
server.listen(5050);Sometimes when you have received a HTML/XML document from the server of origin you would like to modify it before forwarding it on.
Harmon allows you to do this in a streaming style so as to keep the pressure on the proxy to a minimum.
var http = require('http'),
httpProxy = require('http-proxy');
//
// Create a proxy server with latency
//
var proxy = httpProxy.createProxyServer();
//
// Create your server that makes an operation that waits a while
// and then proxies the request
//
http.createServer(function (req, res) {
// This simulates an operation that takes 500ms to execute
setTimeout(function () {
proxy.web(req, res, {
target: 'http://localhost:9008'
});
}, 500);
}).listen(8008);
//
// Create your target server
//
http.createServer(function (req, res) {
res.writeHead(200, { 'Content-Type': 'text/plain' });
res.write('request successfully proxied to: ' + req.url + '\n' + JSON.stringify(req.headers, true, 2));
res.end();
}).listen(9008);You can activate the validation of a secure SSL certificate to the target connection (avoid self signed certs), just set secure: true in the options.
//
// Create the HTTPS proxy server in front of a HTTP server
//
httpProxy.createServer({
target: {
host: 'localhost',
port: 9009
},
ssl: {
key: fs.readFileSync('valid-ssl-key.pem', 'utf8'),
cert: fs.readFileSync('valid-ssl-cert.pem', 'utf8')
}
}).listen(8009);//
// Create the proxy server listening on port 443
//
httpProxy.createServer({
ssl: {
key: fs.readFileSync('valid-ssl-key.pem', 'utf8'),
cert: fs.readFileSync('valid-ssl-cert.pem', 'utf8')
},
target: 'https://localhost:9010',
secure: true // Depends on your needs, could be false.
}).listen(443);You can activate the websocket support for the proxy using ws:true in the options.
//
// Create a proxy server for websockets
//
httpProxy.createServer({
target: 'ws://localhost:9014',
ws: true
}).listen(8014);Also you can proxy the websocket requests just calling the ws(req, socket, head) method.
//
// Setup our server to proxy standard HTTP requests
//
var proxy = new httpProxy.createProxyServer({
target: {
host: 'localhost',
port: 9015
}
});
var proxyServer = http.createServer(function (req, res) {
proxy.web(req, res);
});
//
// Listen to the `upgrade` event and proxy the
// WebSocket requests as well.
//
proxyServer.on('upgrade', function (req, socket, head) {
proxy.ws(req, socket, head);
});
proxyServer.listen(8015);