http-proxy-rules and Websockets - node.js

I haven't been able to find any documentation/answer to my needs.
I'm in something of a pickle. I'm developing a websocket application which will allow module expansion by creating new services (websocket servers). Of course this means more ports to connect to. The problem is, our corporate policy only has a very few ports open so I need to proxy my requests.
I've read many answers saying to use NGINX, but I simply can't. First off I'm running windows, second our company is very strict on what can and can't be used. I am able to install any node module, though. I've attempted to use the http-proxy module along with http-proxy-rules.
The problem is, I'm getting 404's on every websocket request. I'll note that the default proxy (for normal webservice, not sockets) is working 100% fine.
Here's my current code:
var http = require('http'),
httpProxy = require('http-proxy'),
HttpProxyRules = require('http-proxy-rules');
// Set up proxy rules instance
var proxyRules = new HttpProxyRules({
rules: {
'.*/ws/admin': 'http://localhost:26266', // Rule for websocket service (admin module)
'.*/ws/quickquery': 'http://localhost:26265' // Rule for websocket service (quickquery module)
},
default: 'http://Surface.levisinger.com:8080' // default target
});
// Create reverse proxy instance
var proxy = httpProxy.createProxy();
// Create http server that leverages reverse proxy instance
// and proxy rules to proxy requests to different targets
http.createServer(function(req, res) {
// a match method is exposed on the proxy rules instance
// to test a request to see if it matches against one of the specified rules
var target = proxyRules.match(req);
if (target) {
//console.log(req);
console.log("Returning " + target + " for " + req.headers.host);
return proxy.web(req, res, {
target: target,
ws: true
});
}
res.writeHead(500, { 'Content-Type': 'text/plain' });
res.end('The request url and path did not match any of the listed rules!');
}).listen(5050);
My client code connecting to the websocket looks like this:
var servPath = (cliSettings["AppPaths"]["Admin"] == null) ? 'http://' + window.location.hostname + ':5050' : cliSettings["AppPaths"]["Admin"],
AdminIO = new io(servPath, {
extraHeaders: {
Service: "Admin"
},
path: '/ws/admin'})
...
And the websocket server is called like this:
io = require('socket.io').listen(26266,{ path: '/ws/admin'}) // can use up to 26484
I really hope someone here will have an idea. Thanks!

Figured out how to do this. There are a few things to this...
1. You have to use custom websocket paths if you want to proxy them.
2. You must give the entire path to the websocket when proxying them.
3. You'll need to specify an event to handle websocket (ws) traffic.
Here's an example for you all.
+++++++++++++++++++++++++++++++++++++++++++++
+++++++++++++++++++++++++++++++++++++++++++++
Proxy Server:
var ini = require('node-ini'),
conf = ini.parseSync('../settings/config.ini'),
http = require('http'),
httpProxy = require('http-proxy'),
HttpProxyRules = require('http-proxy-rules');
// Set up proxy rules instance
var proxyRules = new HttpProxyRules({
rules: {
'.*/ws/remote': 'http://' + conf["Server"]["binding"] + ':26267/ws/remote',
'.*/ws/admin': 'http://' + conf["Server"]["binding"] + ':26266/ws/admin', // Rule for websocket service (admin module)
'.*/ws/quickquery': 'http://' + conf["Server"]["binding"] + ':26265/ws/quickquery' // Rule for websocket service (quickquery module)
},
default: 'http://' + conf["Server"]["binding"] + ':8080' // default target
});
// Create reverse proxy instance
var proxy = httpProxy.createProxy();
// Create http server that leverages reverse proxy instance
// and proxy rules to proxy requests to different targets
var proxyServer = http.createServer(function(req, res) {
// a match method is exposed on the proxy rules instance
// to test a request to see if it matches against one of the specified rules
var target = proxyRules.match(req);
if (target) {
//console.log(req.url);
//console.log("Returning " + target + " for " + req.url);
return proxy.web(req, res, {
target: target,
ws: true
});
}
res.writeHead(500, { 'Content-Type': 'text/plain' });
res.end('The request url and path did not match any of the listed rules!');
}).listen(conf["Server"]["port"]);
//
// Listen to the `upgrade` event and proxy the
// WebSocket requests as well.
//
proxyServer.on('upgrade', function (req, socket, head) {
var target = proxyRules.match(req);
if (target) {
return proxy.ws(req, socket, head, { target: target });
}
});
process.on('SIGINT', function() {
db.stop(function(err) {
process.exit(err ? 1 : 0);
});
});
Websocket Server socket listener:
io = require('socket.io').listen(26266,{ path: '/ws/admin'});
Connect to websocket from client page:
AdminIO = new io({path: '/ws/admin'});
+++++++++++++++++++++++++++++++++++++++++++++
+++++++++++++++++++++++++++++++++++++++++++++
The example above will proxy my "admin" connection, which is running on port 26266, through port 80. (I'd of course recommend using 443/SSL in every situation, but that's a bit more complex).
Hope this helps someone!

Related

WebSocket Proxy failing with Node.js and Angular. Unexpected response code: 404

I am trying to get up to speed on proxying websockets. I have some angular code that I modified from a tutorial which tests websocket connections against echo.websocket.org. The code works fine by itself.
<!DOCTYPE html>
<html>
<meta charset = "utf-8" />
<title>WebSocket Test</title>
<script language = "javascript" type = "text/javascript">
var wsUri = "ws://echo.websocket.org/";
//var wsUri = "ws://localhost:8015"
var output;
var success = 0;
var failure = 0;
function init() {
output = document.getElementById("output");
output.innerHTML = "";
testWebSocket();
writeScore();
}
function testWebSocket() {
websocket = new WebSocket(wsUri);
websocket.onopen = function(evt) {
onOpen(evt)
};
websocket.onclose = function(evt) {
onClose(evt)
};
websocket.onmessage = function(evt) {
onMessage(evt)
};
websocket.onerror = function(evt) {
onError(evt)
};
}
function onOpen(evt) {
writeToScreen("CONNECTED");
doSend("WebSocket rocks");
success = success +1;
}
function onClose(evt) {
writeToScreen("DISCONNECTED");
}
function onMessage(evt) {
writeToScreen('<span style = "color: blue;">RESPONSE: ' +
evt.data+'</span>'); websocket.close();
}
function onError(evt) {
writeToScreen('<span style = "color: red;">ERROR:</span> '
+ evt.data);
failure = failure +1;
}
function doSend(message) {
writeToScreen("SENT: " + message); websocket.send(message);
}
function writeToScreen(message) {
var pre = document.createElement("p");
pre.style.wordWrap = "break-word";
pre.innerHTML = message;
output.appendChild(pre);
}
function writeScore(){
var pScore = document.createElement("p");
pScore.style.wordWrap = "break-word";
pScore.innerHTML = "Success "+ success+ " Failures "+ failure;
output.appendChild(pScore);
}
window.addEventListener("load", init, false);
</script>
<h2>WebSocket Test</h2>
<div id = "output"></div>
</html>
following the instructions from https://github.com/nodejitsu/node-http-proxy#proxying-websockets
I have tried to set up a simple proxy 2 different ways that will forward the angular page's websocket requests to the same echo.websocket.org connection by altering the wsUri variable in the angular code to point at one of the servers created in this code.
///
// Setup our server to proxy standard HTTP requests
//
var httpProxy = require('http-proxy');
var http = require('http');
var proxy = new httpProxy.createProxyServer({
target: {
host: 'echo.websocket.org',
port: 80
}
});
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) {
console.log(socket);
proxy.ws(req, socket, head);
});
proxyServer.listen(8015);
var test = httpProxy.createServer({
target: 'ws://echo.websocket.org',
ws: true
});
test.listen(8014);
Unfortunately the proxied request (for both the sever listening on port 8014 and 8015) triggers the angular websocket.onerror event handler providing me a less than helpful message of 'undefined' for evt.data.
Update:
Chrome displays the following error message in developer tools when I try to open the webpage using the localhost proxies.
index.htm:29 WebSocket connection to 'ws://localhost:8015/' failed:
Error during WebSocket handshake: Unexpected response code: 404
Firefox displays the following in it's "Web Console"
Firefox can’t establish a connection to the server at ws://localhost:8015/.
However, the upgrade event is firing as I am seeing the Node's console display the socket information from the console.log() line of the Node JS code. That leads me to believe that the localhost server is being found, begging the question for the origin of the 404 error. I'm not sure if it is related to the finding the proxy (which is having its http upgrade event triggered), or the proxy's target.
How do I get Node JS to proxy the angular websocket connection that works fine when no proxy is between the browser and echo.websocket.org?
TLDR;
it is related to setting up the Host: foo.com header before forwarding the proxied request.
Basically, Error during WebSocket handshake: Unexpected response code: 404
means that it actually could not establish any connection with given that wsUri.
As seen from this issue, changeOrigin proposed to be true as default.
However, it is false in our case (by default). So, forwarded request is invalid/malformed without properly setting up the HTTP Host header. You may try to debug this further to see the real HTTP attributes, headers, etc.
Also,
autoRewrite attribute rewrites the location host/port on (201/301/302/307/308) redirects based on requested host/port.
Try to add properties below as createServer() arguments:
autoRewrite: true,
changeOrigin: true,
So, it becomes:
const test = httpProxy.createServer({
target: 'ws://echo.websocket.org',
ws: true,
autoRewrite: true,
changeOrigin: true,
});
test.listen(8014);
Hope it helps!

node.js node-http-proxy: How to avoid exceptions with WebSocket when target in proxy.web

Using http-proxy (aka node-http-proxy) in node.js, I am having trouble figuring out how to proxy web sockets when the target is determined dynamically (i.e. when processing the request).
Looking at the documentation:
https://github.com/nodejitsu/node-http-proxy
There is an example that shows being able to set the target when processing 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);
There is another example farther down showing support for websockets via proxy.ws(), but it shows the target being set statically rather than depending on the request:
//
// 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);
I took the first example and added the proxyServer.on('upgrade'... proxy.ws() ... stuff from the second example in order to get an example that sets the target while processing the request and also supports websockets. HTTP web pages seem to work fine, but it throws an exception when handling a websocket request.
'use strict';
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' });
});
//
// Listen to the `upgrade` event and proxy the
// WebSocket requests as well.
//
server.on('upgrade', function (req, socket, head) {
proxy.ws(req, socket, head);
});
console.log("listening on port 5050")
server.listen(5050);
The exception happens in the proxy.ws(req, socket, head) call:
Error: Must provide a proper URL as target
at ProxyServer.<anonymous> (...../node_modules/http-proxy/lib/http-proxy/index.js:68:35)
at Server.<anonymous> (...../poc.js:26:9) // the location in my sample code of the proxy.ws(req, socket, head) above
at emitThree (events.js:116:13)
at Server.emit (events.js:194:7)
at onParserExecuteCommon (_http_server.js:409:14)
at HTTPParser.onParserExecute (_http_server.js:377:5)
The code in http-proxy/index.js:68:35 throws this exception if there is no .target or .forward member of the options.
How do I set the target on a per request basis and also get websockets to work?
I have an answer. After looking at this question by Conrad and the comments, and then experimenting:
single-proxyserver-to-multiple-targets
proxy.ws can take an additional argument of options, just like proxy.web.
Here is the working code.
'use strict';
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' });
});
//
// Listen to the `upgrade` event and proxy the
// WebSocket requests as well.
//
server.on('upgrade', function (req, socket, head) {
proxy.ws(req, socket, head, { target: 'ws://127.0.0.1:5060' });
});
console.log("listening on port 5050")
server.listen(5050);

Forward http proxy using node http proxy

I'm using the node-http-proxy library to create a forward proxy server.
I eventually plan to use some middleware to modify the html code on the fly.
This is how my proxy server code looks like
var httpProxy = require('http-proxy')
httpProxy.createServer(function(req, res, proxy) {
var urlObj = url.parse(req.url);
console.log("actually proxying requests")
req.headers.host = urlObj.host;
req.url = urlObj.path;
proxy.proxyRequest(req, res, {
host : urlObj.host,
port : 80,
enable : { xforward: true }
});
}).listen(9000, function () {
console.log("Waiting for requests...");
});
Now I modify chrome's proxy setting, and enable web proxy server address as localhost:9000
However every time I visit a normal http website, my server crashes saying "Error: Must provide a proper URL as target"
I am new at nodejs, and I don't entirely understand what I'm doing wrong here?
To use a dynamic target, you should create a regular HTTP server that uses a proxy instance for which you can set the target dynamically (based on the incoming request).
A bare bones forwarding proxy:
const http = require('http');
const httpProxy = require('http-proxy');
const proxy = httpProxy.createProxyServer({});
http.createServer(function(req, res) {
proxy.web(req, res, { target: req.url });
}).listen(9000, () => {
console.log("Waiting for requests...");
});

Router in Node http proxy

Can anyone please explain what the router in options does in this code. I got this code from a blog. I am trying to implement node http-proxy.
var http = require('http'),
httpProxy = require('http-proxy');
//
//Leave out the hostnameOnly field this time, or set it to false...
//
var options = {
router: {
'domainone.com/appone': '127.0.0.1:9000',
'domainone.com/apptwo': '127.0.0.1:9001',
'domaintwo.net/differentapp': '127.0.0.1:9002'
}
}
//
//...and then pass in your options like last time.
//
var proxyServer = httpProxy.createServer(options).listen(80);
//
// ...and a simple http server to show us our request back.
//
http.createServer(function (req, res) {
res.writeHead(200, { 'Content-Type': 'text/plain' });
res.write('request successfully proxied!' + '\n' + JSON.stringify(req.headers, true, 2));
res.end();
}).listen(9000);
The proxy library will take all incoming requests and attempt to match it with a rule in your router table. Assuming it finds a match, it will forward that request to the IP address associated with the DNS name you provided.
For example, requests going to domainone.com/appone will be forwarded to 127.0.0.1:9000
One problem that I see here is that you are listening on port 9000, and your first rule re-routes to 127.0.0.1:9000.

creating a forward https proxy using http-node-proxy

I am trying to create a forward proxy capable of handling HTTPS websites as well. I am trying to observe and modify traffic for different sites. This is my code which works for http sites but not for https sites.
httpProxy.createServer(function(req, res, next) {
//custom logic
next();
}, function(req, res) {
var proxy = new httpProxy.RoutingProxy();
var buffer = httpProxy.buffer(req);
var urlObj = url.parse(req.url);
req.headers.host = urlObj.host;
req.url = urlObj.path;
console.log(urlObj.protocol);
setTimeout(function() {
proxy.proxyRequest(req, res, {
host: urlObj.host,
port: 80,
buffer: buffer,
}
)}, 5000);
}).listen(9000, function() {
console.log("Waiting for requests...");
});
Thanks for your help guys!
There are https options which must be specified when handling the https traffic. Here is what I am doing in my proxy setup.
var fs = require('fs'),
httpProxy = require('http-proxy');
var proxyTable = {};
proxyTable['domain.com'] = 'localhost:3001';
proxyTable['domain.com/path'] = 'localhost:3002';
proxyTable['sub.domain.com'] = 'localhost:3003';
var httpOptions = {
router: proxyTable
};
var httpsOptions = {
router: proxyTable,
https: {
passphrase: 'xxxxxxx',
key: fs.readFileSync('/path/to/key'),
ca: fs.readFileSync('/path/to/ca'),
cert: fs.readFileSync('/path/to/crt')}
};
httpProxy.createServer(httpOptions).listen(80);
httpProxy.createServer(httpsOptions).listen(443);
The documentation for https is on their github page as well.
https://github.com/nodejitsu/node-http-proxy
If you're just doing a forward proxy there's a few things you'll have to take into account.
A regular request is NOT triggered on a proxy for a HTTPS request - instead you'll see a HTTP CONNECT.
Here's the sequence flow you'll need to handle.
CONNECT event is sent from the browser to the proxy specified in the HTTPS section. You'll catch this here: http://nodejs.org/api/http.html#http_event_connect Note that this comes over the HTTP module, not the HTTPS connection.
You create a new socket connection to the requested domain (or your mapped domain). [srvSocket]
You'll respond back to the CONNECT socket with a 200
You'll write the buffer you received with the CONNECT event to srvSocket, then pipe the two sockets together srvSocket.pipe(socket);
socket.pipe(srvSocket);
Since you're trying to spoof the requested domain locally you'll need a few more things in place
You'll need to generate a root CA.
You will need to import this cert as a trusted authority to your OS
You'll use this cert to create a new key/cert file for the domains you're trying to access
Your mapped hosts will need to respond with the appropriate key/cert file generated in step 3 for EACH domain you are mapping.
https://github.com/substack/bouncy
var bouncy = require('bouncy');
var server = bouncy(function (req, res, bounce) {
if (req.headers.host === 'beep.example.com') {
bounce(8001);
}
else if (req.headers.host === 'boop.example.com') {
bounce(8002);
}
else {
res.statusCode = 404;
res.end('no such host');
}
});
server.listen(8000);
If you specify opts.key and opts.cert, the connection will be set to secure mode using tls. Do this if you want to make an https router.
We can have a middleware as below
request = require("request");
app.use(function (req, res, next) {
request('http://anotherurl.that.serves/the/request').pipe(res);
});
See example https://github.com/manuks/proxy
Basically, underneath the http-proxy npm is some networking libraries Node uses (specifically http://nodejs.org/api/https.html and TLS). Even though my Apache was able to connect me just fine on a self-signed certificate w/o the proxy by accessing it in my browser:
https://localhost:8002
You need to establish a certificate authority to get past the "unable to verify leaf signature" error in Node (I used the SSLCACertificateFile option). Then, you'll get hit with "self_signed_cert_in_chain". This led to some Google results indicating npm abandoned self-signed certificates, but I'm pretty sure this does not regard Node.
What you end up with are some people indicating you use process.env.NODE_TLS_REJECT_UNAUTHORIZED or rejectUnauthorized within your https agent. If you dig through the http-proxy souce, you'll find it accepts an agent option. Use this:
/**
* Module dependencies
*/
// basic includes
express = require('express');
fs = require('fs');
http = require('http');
https = require('https');
httpProxy = require('http-proxy');
require('child_process').spawn(__dirname+'/../../../dependencies/apache/bin/httpd.exe',['-f',__dirname+'/../../../dependencies/apache/conf/httpd-payments.conf']);
var app = module.exports = express();
app.set('port', process.env.PORT || 8001); // we sometimes change the port
// creates an output object for this particular request
//app.use(express.cookieParser(''));
//app.use(express.bodyParser());
//app.use(express.methodOverride());
proxy = httpProxy.createProxyServer();
proxy.on('error', function (err, req, res) {
console.log(err);
res.send(500,err);
res.end();
});
app.all('*',function(req,res,next) {
var options = {
hostname: '127.0.0.1',
port: 8002,
rejectUnauthorized: false,
key: fs.readFileSync(__dirname+"/../../../deployment/server.key.pem"),
cert: fs.readFileSync(__dirname+"/../../../deployment/server.crt.pem")
};
agent = new https.Agent(options);
try {
proxy.web(req,res, {
target: "https://localhost:8002",
proxyTimeout: 30,
agent: agent
});
} catch(e) {
// 500 error
res.send(500,e);
}
})
/**
* Start Server
*/
var options = {
key: fs.readFileSync(__dirname+"/../../../deployment/server.key.pem"),
cert: fs.readFileSync(__dirname+"/../../../deployment/server.crt.pem")
};
server = https.createServer(options,app).listen(app.get('port'), function () {
console.log('Running payments server on port ' + app.get('port'));
});

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