Commit d2b0e439 authored by indexzero's avatar indexzero

[api breaking] Begin refactor to optimize node-http-proxy by managing one...

[api breaking] Begin refactor to optimize node-http-proxy by managing one instance of HttpProxy per `host:port` location
parent db10c4af
...@@ -28,7 +28,6 @@ var util = require('util'), ...@@ -28,7 +28,6 @@ var util = require('util'),
http = require('http'), http = require('http'),
https = require('https'), https = require('https'),
events = require('events'), events = require('events'),
ProxyTable = require('./proxy-table').ProxyTable,
maxSockets = 100; maxSockets = 100;
// //
...@@ -37,110 +36,11 @@ var util = require('util'), ...@@ -37,110 +36,11 @@ var util = require('util'),
require('pkginfo')(module, 'version'); require('pkginfo')(module, 'version');
// //
// Track our own list of agents internal to `node-http-proxy` // ### Export the relevant objects exposed by `node-http-proxy`
// //
var _agents = {}; var HttpProxy = exports.HttpProxy = require('./node-http-proxy/http-proxy').HttpProxy,
ProxyTable = exports.ProxyTable = require('./node-http-proxy/proxy-table').ProxyTable,
// RoutingProxy = exports.RoutingProxy = require('./node-http-proxy/routing-proxy').RoutingProxy;
// ### function _getAgent (host, port, secure)
// #### @host {string} Host of the agent to get
// #### @port {number} Port of the agent to get
// #### @secure {boolean} Value indicating whether or not to use HTTPS
// Retreives an agent from the `http` or `https` module
// and sets the `maxSockets` property appropriately.
//
function _getAgent (host, port, secure) {
var Agent, id = [host, port].join(':');
if (!port) {
port = secure ? 443 : 80;
}
if (!_agents[id]) {
Agent = secure ? https.Agent : http.Agent;
_agents[id] = new Agent({
host: host,
port: port
});
_agents[id].maxSockets = maxSockets;
}
return _agents[id];
}
//
// ### function _getProtocol (secure, outgoing)
// #### @secure {Object|boolean} Settings for `https`
// #### @outgoing {Object} Outgoing request options
// Returns the appropriate protocol based on the settings in
// `secure`. If the protocol is `https` this function will update
// the options in `outgoing` as appropriate by adding `ca`, `key`,
// and `cert` if they exist in `secure`.
//
function _getProtocol (secure, outgoing) {
var protocol = secure ? https : http;
if (typeof secure === 'object') {
outgoing = outgoing || {};
['ca', 'cert', 'key'].forEach(function (prop) {
if (secure[prop]) {
outgoing[prop] = secure[prop];
}
})
}
return protocol;
}
//
// ### function getMaxSockets ()
// Returns the maximum number of sockets
// allowed on __every__ outgoing request
// made by __all__ instances of `HttpProxy`
//
exports.getMaxSockets = function () {
return maxSockets;
};
//
// ### function setMaxSockets ()
// Sets the maximum number of sockets
// allowed on __every__ outgoing request
// made by __all__ instances of `HttpProxy`
//
exports.setMaxSockets = function (value) {
maxSockets = value;
};
//
// ### function stack (middlewares, proxy)
// adapted from https://github.com/creationix/stack
//
exports.stack = function stack (middlewares, proxy) {
var handle;
middlewares.reverse().forEach(function (layer) {
var child = handle;
handle = function (req, res) {
var next = function (err) {
if (err) {
throw err;
//
// TODO: figure out where to send errors.
// return error(req, res, err);
//
}
child(req, res);
}
next.__proto__ = proxy;
layer(req, res, next);
};
});
return handle;
}
// //
// ### function createServer ([port, host, options, handler]) // ### function createServer ([port, host, options, handler])
...@@ -255,59 +155,6 @@ exports.createServer = function () { ...@@ -255,59 +155,6 @@ exports.createServer = function () {
return server; return server;
}; };
//
// ### function HttpProxy (options)
// #### @options {Object} Options for this instance.
// Constructor function for new instances of HttpProxy responsible
// for managing the life-cycle of streaming reverse proxyied HTTP requests.
//
// Example options:
//
// {
// router: {
// 'foo.com': 'localhost:8080',
// 'bar.com': 'localhost:8081'
// },
// forward: {
// host: 'localhost',
// port: 9001
// }
// }
//
var HttpProxy = exports.HttpProxy = function (options) {
events.EventEmitter.call(this);
var self = this;
options = options || {};
//
// Setup basic proxying options
//
this.https = options.https;
this.forward = options.forward;
this.target = options.target || {};
//
// Setup additional options for WebSocket proxying. When forcing
// the WebSocket handshake to change the `sec-websocket-location`
// and `sec-websocket-origin` headers `options.source` **MUST**
// be provided or the operation will fail with an `origin mismatch`
// by definition.
//
this.source = options.source || { host: 'localhost', port: 8000 };
this.changeOrigin = options.changeOrigin || false;
if (options.router) {
this.proxyTable = new ProxyTable(options.router, options.silent, options.hostnameOnly);
this.proxyTable.on('routes', function (routes) {
self.emit('routes', routes);
});
}
};
// Inherit from events.EventEmitter
util.inherits(HttpProxy, events.EventEmitter);
// //
// ### function buffer (obj) // ### function buffer (obj)
// #### @obj {Object} Object to pause events from // #### @obj {Object} Object to pause events from
...@@ -328,8 +175,10 @@ util.inherits(HttpProxy, events.EventEmitter); ...@@ -328,8 +175,10 @@ util.inherits(HttpProxy, events.EventEmitter);
// This simply chooses to manage the scope of the events on a new Object literal as opposed to // This simply chooses to manage the scope of the events on a new Object literal as opposed to
// [on the HttpProxy instance](https://github.com/nodejitsu/node-http-proxy/blob/v0.3.1/lib/node-http-proxy.js#L154). // [on the HttpProxy instance](https://github.com/nodejitsu/node-http-proxy/blob/v0.3.1/lib/node-http-proxy.js#L154).
// //
HttpProxy.prototype.buffer = function (obj) { exports.buffer = function (obj) {
var onData, onEnd, events = []; var events = [],
onData,
onEnd;
obj.on('data', onData = function (data, encoding) { obj.on('data', onData = function (data, encoding) {
events.push(['data', data, encoding]); events.push(['data', data, encoding]);
...@@ -354,567 +203,116 @@ HttpProxy.prototype.buffer = function (obj) { ...@@ -354,567 +203,116 @@ HttpProxy.prototype.buffer = function (obj) {
}; };
// //
// ### function close () // ### function getMaxSockets ()
// Frees the resources associated with this instance, // Returns the maximum number of sockets
// if they exist. // allowed on __every__ outgoing request
// made by __all__ instances of `HttpProxy`
// //
HttpProxy.prototype.close = function () { exports.getMaxSockets = function () {
if (this.proxyTable) { return maxSockets;
this.proxyTable.close();
}
}; };
// //
// ### function proxyRequest (req, res, [port, host, paused]) // ### function setMaxSockets ()
// #### @req {ServerRequest} Incoming HTTP Request to proxy. // Sets the maximum number of sockets
// #### @res {ServerResponse} Outgoing HTTP Request to write proxied data to. // allowed on __every__ outgoing request
// #### @options {Object} Options for the outgoing proxy request. // made by __all__ instances of `HttpProxy`
//
// options.port {number} Port to use on the proxy target host.
// options.host {string} Host of the proxy target.
// options.buffer {Object} Result from `httpProxy.buffer(req)`
// options.https {Object|boolean} Settings for https.
// options.enableXForwarded {boolean} Don't clobber x-forwarded headers to allow layered proxies.
// //
HttpProxy.prototype.proxyRequest = function (req, res, options) { exports.setMaxSockets = function (value) {
var self = this, errState = false, location, outgoing, protocol, reverseProxy; maxSockets = value;
};
//
// Create an empty options hash if none is passed.
// If default options have been passed to the constructor
// of this instance, use them by default.
//
options = options || {};
options.host = options.host || this.target.host;
options.port = options.port || this.target.port;
options.enableXForwarded =
(undefined === options.enableXForwarded ? true : options.enableXForwarded);
//
// Check the proxy table for this instance to see if we need
// to get the proxy location for the request supplied. We will
// always ignore the proxyTable if an explicit `port` and `host`
// arguments are supplied to `proxyRequest`.
//
if (this.proxyTable && !options.host) {
location = this.proxyTable.getProxyLocation(req);
//
// If no location is returned from the ProxyTable instance
// then respond with `404` since we do not have a valid proxy target.
//
if (!location) {
res.writeHead(404);
return res.end();
}
//
// When using the ProxyTable in conjunction with an HttpProxy instance
// only the following arguments are valid:
//
// * `proxy.proxyRequest(req, res, { host: 'localhost' })`: This will be skipped
// * `proxy.proxyRequest(req, res, { buffer: buffer })`: Buffer will get updated appropriately
// * `proxy.proxyRequest(req, res)`: Options will be assigned appropriately.
//
options.port = location.port;
options.host = location.host;
}
//
// Add common proxy headers to the request so that they can
// be availible to the proxy target server:
//
// * `x-forwarded-for`: IP Address of the original request
// * `x-forwarded-proto`: Protocol of the original request
// * `x-forwarded-port`: Port of the original request.
//
if (options.enableXForwarded === true) {
req.headers['x-forwarded-for'] = req.connection.remoteAddress || req.connection.socket.remoteAddress;
req.headers['x-forwarded-port'] = req.connection.remotePort || req.connection.socket.remotePort;
req.headers['x-forwarded-proto'] = res.connection.pair ? 'https' : 'http';
}
//
// Emit the `start` event indicating that we have begun the proxy operation.
//
this.emit('start', req, res, options);
//
// If forwarding is enabled for this instance, foward proxy the
// specified request to the address provided in `this.forward`
//
if (this.forward) {
this.emit('forward', req, res, this.forward);
this._forwardRequest(req);
}
//
// #### function proxyError (err)
// #### @err {Error} Error contacting the proxy target
// Short-circuits `res` in the event of any error when
// contacting the proxy target at `host` / `port`.
//
function proxyError(err) {
errState = true;
//
// Emit an `error` event, allowing the application to use custom
// error handling. The error handler should end the response.
//
if (self.emit('proxyError', err, req, res)) {
return;
}
res.writeHead(500, { 'Content-Type': 'text/plain' });
if (req.method !== 'HEAD') { //
// ### function stack (middlewares, proxy)
// adapted from https://github.com/creationix/stack
//
exports.stack = function stack (middlewares, proxy) {
var handle;
middlewares.reverse().forEach(function (layer) {
var child = handle;
handle = function (req, res) {
var next = function (err) {
if (err) {
throw err;
// //
// This NODE_ENV=production behavior is mimics Express and // TODO: figure out where to send errors.
// Connect. // return error(req, res, err);
// //
if (process.env.NODE_ENV === 'production') {
res.write('Internal Server Error');
}
else {
res.write('An error has occurred: ' + JSON.stringify(err));
} }
child(req, res);
} }
res.end(); next.__proto__ = proxy;
} layer(req, res, next);
outgoing = {
host: options.host,
port: options.port,
agent: _getAgent(options.host, options.port, options.https || this.target.https),
method: req.method,
path: req.url,
headers: req.headers
}; };
protocol = _getProtocol(options.https || this.target.https, outgoing);
// Open new HTTP request to internal resource with will act as a reverse proxy pass
reverseProxy = protocol.request(outgoing, function (response) {
// Process the `reverseProxy` `response` when it's received.
if (response.headers.connection) {
if (req.headers.connection) response.headers.connection = req.headers.connection;
else response.headers.connection = 'close';
}
// Set the headers of the client response
res.writeHead(response.statusCode, response.headers);
// `response.statusCode === 304`: No 'data' event and no 'end'
if (response.statusCode === 304) {
return res.end();
}
// For each data `chunk` received from the `reverseProxy`
// `response` write it to the outgoing `res`.
// If the res socket has been killed already, then write()
// will throw. Nevertheless, try our best to end it nicely.
response.on('data', function (chunk) {
if (req.method !== 'HEAD' && res.writable) {
try {
res.write(chunk);
} catch (er) {
try {
res.end();
} catch (er) {}
}
}
});
// When the `reverseProxy` `response` ends, end the
// corresponding outgoing `res` unless we have entered
// an error state. In which case, assume `res.end()` has
// already been called and the 'error' event listener
// removed.
response.on('end', function () {
if (!errState) {
reverseProxy.removeListener('error', proxyError);
res.end();
// Emit the `end` event now that we have completed proxying
self.emit('end', req, res);
}
});
}); });
// Handle 'error' events from the `reverseProxy`. return handle;
reverseProxy.once('error', proxyError);
// For each data `chunk` received from the incoming
// `req` write it to the `reverseProxy` request.
req.on('data', function (chunk) {
if (!errState) {
reverseProxy.write(chunk);
}
});
//
// When the incoming `req` ends, end the corresponding `reverseProxy`
// request unless we have entered an error state.
//
req.on('end', function () {
if (!errState) {
reverseProxy.end();
}
});
// If we have been passed buffered data, resume it.
if (options.buffer && !errState) {
options.buffer.resume();
}
}; };
// //
// ### @private function _forwardRequest (req) // ### function _getAgent (host, port, secure)
// #### @req {ServerRequest} Incoming HTTP Request to proxy. // #### @options {Object} Options to use when creating the agent.
// Forwards the specified `req` to the location specified
// by `this.forward` ignoring errors and the subsequent response.
//
HttpProxy.prototype._forwardRequest = function (req) {
var self = this, port, host, outgoing, protocol, forwardProxy;
port = this.forward.port;
host = this.forward.host;
outgoing = {
host: host,
port: port,
agent: _getAgent(host, port, this.forward.https),
method: req.method,
path: req.url,
headers: req.headers
};
// Force the `connection` header to be 'close' until
// node.js core re-implements 'keep-alive'.
outgoing.headers['connection'] = 'close';
protocol = _getProtocol(this.forward.https, outgoing);
// Open new HTTP request to internal resource with will act as a reverse proxy pass
forwardProxy = protocol.request(outgoing, function (response) {
//
// Ignore the response from the forward proxy since this is a 'fire-and-forget' proxy.
// Remark (indexzero): We will eventually emit a 'forward' event here for performance tuning.
//
});
// Add a listener for the connection timeout event.
//
// Remark: Ignoring this error in the event
// forward target doesn't exist.
//
forwardProxy.once('error', function (err) { });
// Chunk the client request body as chunks from the proxied request come in
req.on('data', function (chunk) {
forwardProxy.write(chunk);
})
// At the end of the client request, we are going to stop the proxied request
req.on('end', function () {
forwardProxy.end();
});
};
// //
// ### function proxyWebSocketRequest (req, socket, head, options) // {
// #### @req {ServerRequest} Websocket request to proxy. // host: 'localhost',
// #### @socket {net.Socket} Socket for the underlying HTTP request // port: 9000,
// #### @head {string} Headers for the Websocket request. // https: true,
// #### @options {Object} Options to use when proxying this request. // maxSockets: 100
// }
// //
// options.port {number} Port to use on the proxy target host. // Createsan agent from the `http` or `https` module
// options.host {string} Host of the proxy target. // and sets the `maxSockets` property appropriately.
// options.buffer {Object} Result from `httpProxy.buffer(req)`
// options.https {Object|boolean} Settings for https.
// //
HttpProxy.prototype.proxyWebSocketRequest = function (req, socket, head, options) { exports._getAgent = function _getAgent (options) {
var self = this, if (!options || !options.host) {
listeners = {}, throw new Error('`options.host` is required to create an Agent.');
errState = false,
CRLF = '\r\n',
outgoing;
options = options || {};
options.host = options.host || this.target.host;
options.port = options.port || this.target.port;
if (this.proxyTable && !options.host) {
location = this.proxyTable.getProxyLocation(req);
if (!location) {
return socket.destroy();
}
options.port = location.port;
options.host = location.host;
}
//
// WebSocket requests must have the `GET` method and
// the `upgrade:websocket` header
//
if (req.method !== 'GET' || req.headers.upgrade.toLowerCase() !== 'websocket') {
//
// This request is not WebSocket request
//
return;
}
//
// Helper function for setting appropriate socket values:
// 1. Turn of all bufferings
// 2. For server set KeepAlive
// 3. For client set encoding
//
function _socket(socket, keepAlive) {
socket.setTimeout(0);
socket.setNoDelay(true);
if (keepAlive) {
if (socket.setKeepAlive) {
socket.setKeepAlive(true, 0);
}
else if (socket.pair.cleartext.socket.setKeepAlive) {
socket.pair.cleartext.socket.setKeepAlive(true, 0);
}
}
else {
socket.setEncoding('utf8');
}
}
//
// On `upgrade` from the Agent socket, listen to
// the appropriate events.
//
function onUpgrade (reverseProxy, proxySocket) {
if (!reverseProxy) {
proxySocket.end();
socket.end();
return;
}
//
// Any incoming data on this WebSocket to the proxy target
// will be written to the `reverseProxy` socket.
//
proxySocket.on('data', listeners.onIncoming = function (data) {
if (reverseProxy.incoming.socket.writable) {
try {
self.emit('websocket:outgoing', req, socket, head, data);
reverseProxy.incoming.socket.write(data);
}
catch (e) {
reverseProxy.incoming.socket.end();
proxySocket.end();
}
}
});
//
// Any outgoing data on this Websocket from the proxy target
// will be written to the `proxySocket` socket.
//
reverseProxy.incoming.socket.on('data', listeners.onOutgoing = function(data) {
try {
self.emit('websocket:incoming', reverseProxy, reverseProxy.incoming, head, data);
proxySocket.write(data);
}
catch (e) {
proxySocket.end();
socket.end();
} }
});
// if (!options.port) {
// Helper function to detach all event listeners options.port = options.https ? 443 : 80;
// from `reverseProxy` and `proxySocket`.
//
function detach() {
proxySocket.removeListener('end', listeners.onIncomingClose);
proxySocket.removeListener('data', listeners.onIncoming);
reverseProxy.incoming.socket.removeListener('end', listeners.onOutgoingClose);
reverseProxy.incoming.socket.removeListener('data', listeners.onOutgoing);
} }
// var Agent = options.https ? https.Agent : http.Agent,
// If the incoming `proxySocket` socket closes, then agent;
// detach all event listeners.
//
proxySocket.on('end', listeners.onIncomingClose = function() {
reverseProxy.incoming.socket.end();
detach();
// Emit the `end` event now that we have completed proxying
self.emit('websocket:end', req, socket, head);
});
// agent = new Agent({
// If the `reverseProxy` socket closes, then detach all
// event listeners.
//
reverseProxy.incoming.socket.on('end', listeners.onOutgoingClose = function() {
proxySocket.end();
detach();
});
};
// Setup the incoming client socket.
_socket(socket);
function getPort (port) {
port = port || 80;
return port - 80 === 0 ? '' : ':' + port
}
//
// Get the protocol, and host for this request and create an instance
// of `http.Agent` or `https.Agent` from the pool managed by `node-http-proxy`.
//
var protocolName = options.https || this.target.https ? 'https' : 'http',
portUri = getPort(this.source.port),
remoteHost = options.host + portUri,
agent = _getAgent(options.host, options.port, options.https || this.target.https);
// Change headers (if requested).
if (this.changeOrigin) {
req.headers.host = remoteHost;
req.headers.origin = protocolName + '://' + remoteHost;
}
//
// Make the outgoing WebSocket request
//
outgoing = {
host: options.host, host: options.host,
port: options.port, port: options.port
method: 'GET',
path: req.url,
headers: req.headers,
};
var reverseProxy = agent.appendMessage(outgoing);
//
// On any errors from the `reverseProxy` emit the
// `webSocketProxyError` and close the appropriate
// connections.
//
function proxyError (err) {
reverseProxy.end();
if (self.emit('webSocketProxyError', req, socket, head)) {
return;
}
socket.end();
}
//
// Here we set the incoming `req`, `socket` and `head` data to the outgoing
// request so that we can reuse this data later on in the closure scope
// available to the `upgrade` event. This bookkeeping is not tracked anywhere
// in nodejs core and is **very** specific to proxying WebSockets.
//
reverseProxy.agent = agent;
reverseProxy.incoming = {
request: req,
socket: socket,
head: head
};
//
// If the agent for this particular `host` and `port` combination
// is not already listening for the `upgrade` event, then do so once.
// This will force us not to disconnect.
//
// In addition, it's important to note the closure scope here. Since
// there is no mapping of the
//
if (!agent._events || agent._events['upgrade'].length === 0) {
agent.on('upgrade', function (_, remoteSocket, head) {
//
// Prepare the socket for the reverseProxy request and begin to
// stream data between the two sockets. Here it is important to
// note that `remoteSocket._httpMessage === reverseProxy`.
//
_socket(remoteSocket, true);
onUpgrade(remoteSocket._httpMessage, remoteSocket);
}); });
}
// agent.maxSockets = options.maxSockets || maxSockets;
// If the reverseProxy connection has an underlying socket,
// then execute the WebSocket handshake.
//
if (typeof reverseProxy.socket !== 'undefined') {
reverseProxy.socket.on('data', function handshake (data) {
//
// Ok, kind of harmfull part of code. Socket.IO sends a hash
// at the end of handshake if protocol === 76, but we need
// to replace 'host' and 'origin' in response so we split
// data to printable data and to non-printable. (Non-printable
// will come after double-CRLF).
//
var sdata = data.toString();
// Get the Printable data return agent;
sdata = sdata.substr(0, sdata.search(CRLF + CRLF)); }
// Get the Non-Printable data //
data = data.slice(Buffer.byteLength(sdata), data.length); // ### function _getProtocol (options)
// #### @options {Object} Options for the proxy target.
// Returns the appropriate node.js core protocol module (i.e. `http` or `https`)
// based on the `options` supplied.
//
exports._getProtocol = function _getProtocol (options) {
return options.https ? https : http;
};
if (self.https && !self.target.https) { //
// // ### function _getBase (options)
// If the proxy server is running HTTPS but the client is running // #### @options {Object} Options for the proxy target.
// HTTP then replace `ws` with `wss` in the data sent back to the client. // Returns the relevate base object to create on outgoing proxy request.
// // If `options.https` are supplied, this function respond with an object
sdata = sdata.replace('ws:', 'wss:'); // containing the relevant `ca`, `key`, and `cert` properties.
} //
exports._getBase = function _getBase (options) {
var result = {};
try { if (typeof options.https === 'object') {
// ['ca', 'cert', 'key'].forEach(function (key) {
// Write the printable and non-printable data to the socket if (options.https[key]) {
// from the original incoming request. result[key] = options.https[key];
//
self.emit('websocket:handshake', req, socket, head, sdata, data);
socket.write(sdata);
socket.write(data);
}
catch (ex) {
proxyError(ex)
} }
// Catch socket errors
socket.on('error', proxyError);
// Remove data listener now that the 'handshake' is complete
reverseProxy.socket.removeListener('data', handshake);
}); });
} }
reverseProxy.on('error', proxyError); return result;
try {
//
// Attempt to write the upgrade-head to the reverseProxy request.
//
reverseProxy.write(head);
}
catch (ex) {
proxyError(ex);
}
//
// If we have been passed buffered data, resume it.
//
if (options.buffer && !errState) {
options.buffer.resume();
}
}; };
\ No newline at end of file
/*
node-http-proxy.js: http proxy for node.js
Copyright (c) 2010 Charlie Robbins, Mikeal Rogers, Marak Squires, Fedor Indutny
Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:
The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
var events = require('events'),
util = require('util'),
httpProxy = require('../node-http-proxy');
//
// ### function HttpProxy (options)
// #### @options {Object} Options for this instance.
// Constructor function for new instances of HttpProxy responsible
// for managing the life-cycle of streaming reverse proxyied HTTP requests.
//
// Example options:
//
// {
// target: {
// host: 'localhost',
// port: 9000
// },
// forward: {
// host: 'localhost',
// port: 9001
// }
// }
//
var HttpProxy = exports.HttpProxy = function (options) {
if (!options || !options.target) {
throw new Error('Both `options` and `options.target` are required.');
}
events.EventEmitter.call(this);
var self = this;
//
// Setup basic proxying options:
//
// * forward {Object} Options for a forward-proxy (if-any)
// * target {Object} Options for the **sole** proxy target of this instance
//
this.forward = options.forward;
this.target = options.target;
//
// Setup the necessary instances instance variables for
// the `target` and `forward` `host:port` combinations
// used by this instance.
//
// * agent {http[s].Agent} Agent to be used by this instance.
// * protocol {http|https} Core node.js module to make requests with.
// * base {Object} Base object to create when proxying containing any https settings.
//
function setupProxy (key) {
self[key].agent = httpProxy._getAgent(self[key]);
self[key].protocol = httpProxy._getProtocol(self[key]);
self[key].base = httpProxy._getBase(self[key]);
}
setupProxy('target')
if (this.forward) { setupProxy('forward') }
//
// Setup opt-in features
//
this.enable = options.enable || {};
this.enable.xforward = typeof this.enable.xforward === 'boolean'
? this.enable.xforward
: true;
//
// Setup additional options for WebSocket proxying. When forcing
// the WebSocket handshake to change the `sec-websocket-location`
// and `sec-websocket-origin` headers `options.source` **MUST**
// be provided or the operation will fail with an `origin mismatch`
// by definition.
//
this.source = options.source || { host: 'localhost', port: 8000 };
this.changeOrigin = options.changeOrigin || false;
};
// Inherit from events.EventEmitter
util.inherits(HttpProxy, events.EventEmitter);
//
// ### function proxyRequest (req, res, [port, host, paused])
// #### @req {ServerRequest} Incoming HTTP Request to proxy.
// #### @res {ServerResponse} Outgoing HTTP Request to write proxied data to.
// #### @buffer {Object} Result from `httpProxy.buffer(req)`
//
HttpProxy.prototype.proxyRequest = function (req, res, buffer) {
var self = this,
errState = false,
outgoing = new Object(this.target.base),
reverseProxy;
//
// Add common proxy headers to the request so that they can
// be availible to the proxy target server:
//
// * `x-forwarded-for`: IP Address of the original request
// * `x-forwarded-proto`: Protocol of the original request
// * `x-forwarded-port`: Port of the original request.
//
if (this.enable.xforward) {
req.headers['x-forwarded-for'] = req.connection.remoteAddress || req.connection.socket.remoteAddress;
req.headers['x-forwarded-port'] = req.connection.remotePort || req.connection.socket.remotePort;
req.headers['x-forwarded-proto'] = res.connection.pair ? 'https' : 'http';
}
//
// Emit the `start` event indicating that we have begun the proxy operation.
//
this.emit('start', req, res, this.target);
//
// If forwarding is enabled for this instance, foward proxy the
// specified request to the address provided in `this.forward`
//
if (this.forward) {
this.emit('forward', req, res, this.forward);
this._forwardRequest(req);
}
//
// #### function proxyError (err)
// #### @err {Error} Error contacting the proxy target
// Short-circuits `res` in the event of any error when
// contacting the proxy target at `host` / `port`.
//
function proxyError(err) {
errState = true;
//
// Emit an `error` event, allowing the application to use custom
// error handling. The error handler should end the response.
//
if (self.emit('proxyError', err, req, res)) {
return;
}
res.writeHead(500, { 'Content-Type': 'text/plain' });
if (req.method !== 'HEAD') {
//
// This NODE_ENV=production behavior is mimics Express and
// Connect.
//
if (process.env.NODE_ENV === 'production') {
res.write('Internal Server Error');
}
else {
res.write('An error has occurred: ' + JSON.stringify(err));
}
}
res.end();
}
//
// Setup outgoing proxy with relevant properties.
//
outgoing.host = this.target.host;
outgoing.port = this.target.port;
outgoing.agent = this.target.agent;
outgoing.method = req.method;
outgoing.path = req.url;
outgoing.headers = req.headers;
//
// Open new HTTP request to internal resource with will act
// as a reverse proxy pass
//
reverseProxy = this.target.protocol.request(outgoing, function (response) {
//
// Process the `reverseProxy` `response` when it's received.
//
if (response.headers.connection) {
if (req.headers.connection) { response.headers.connection = req.headers.connection }
else { response.headers.connection = 'close' }
}
// Set the headers of the client response
res.writeHead(response.statusCode, response.headers);
// If `response.statusCode === 304`: No 'data' event and no 'end'
if (response.statusCode === 304) {
return res.end();
}
//
// For each data `chunk` received from the `reverseProxy`
// `response` write it to the outgoing `res`.
// If the res socket has been killed already, then write()
// will throw. Nevertheless, try our best to end it nicely.
//
response.on('data', function (chunk) {
if (req.method !== 'HEAD' && res.writable) {
try {
res.write(chunk);
}
catch (er) {
try { res.end() }
catch (er) {}
}
}
});
//
// When the `reverseProxy` `response` ends, end the
// corresponding outgoing `res` unless we have entered
// an error state. In which case, assume `res.end()` has
// already been called and the 'error' event listener
// removed.
//
response.on('end', function () {
if (!errState) {
reverseProxy.removeListener('error', proxyError);
res.end();
// Emit the `end` event now that we have completed proxying
self.emit('end', req, res);
}
});
});
//
// Handle 'error' events from the `reverseProxy`.
//
reverseProxy.once('error', proxyError);
//
// For each data `chunk` received from the incoming
// `req` write it to the `reverseProxy` request.
//
req.on('data', function (chunk) {
if (!errState) {
reverseProxy.write(chunk);
}
});
//
// When the incoming `req` ends, end the corresponding `reverseProxy`
// request unless we have entered an error state.
//
req.on('end', function () {
if (!errState) {
reverseProxy.end();
}
});
// If we have been passed buffered data, resume it.
if (buffer && !errState) {
buffer.resume();
}
};
//
// ### @private function _forwardRequest (req)
// #### @req {ServerRequest} Incoming HTTP Request to proxy.
// Forwards the specified `req` to the location specified
// by `this.forward` ignoring errors and the subsequent response.
//
HttpProxy.prototype._forwardRequest = function (req) {
var self = this,
outgoing = new Object(this.forward.base),
forwardProxy;
//
// Setup outgoing proxy with relevant properties.
//
outgoing.host = this.forward.host;
outgoing.port = this.forward.port,
outgoing.agent = this.forward.agent;
outgoing.method = req.method;
outgoing.path = req.url;
outgoing.headers = req.headers;
//
// Open new HTTP request to internal resource with will
// act as a reverse proxy pass.
//
forwardProxy = this.forward.protocol.request(outgoing, function (response) {
//
// Ignore the response from the forward proxy since this is a 'fire-and-forget' proxy.
// Remark (indexzero): We will eventually emit a 'forward' event here for performance tuning.
//
});
//
// Add a listener for the connection timeout event.
//
// Remark: Ignoring this error in the event
// forward target doesn't exist.
//
forwardProxy.once('error', function (err) { });
//
// Chunk the client request body as chunks from
// the proxied request come in
//
req.on('data', function (chunk) {
forwardProxy.write(chunk);
})
//
// At the end of the client request, we are going to
// stop the proxied request
//
req.on('end', function () {
forwardProxy.end();
});
};
//
// ### function proxyWebSocketRequest (req, socket, head, options)
// #### @req {ServerRequest} Websocket request to proxy.
// #### @socket {net.Socket} Socket for the underlying HTTP request
// #### @head {string} Headers for the Websocket request.
// #### @buffer {Object} Result from `httpProxy.buffer(req)`
// Performs a WebSocket proxy operation to the location specified by
// `this.target`.
//
HttpProxy.prototype.proxyWebSocketRequest = function (req, socket, head, buffer) {
var self = this,
outgoing = new Object(this.target.base);
listeners = {},
errState = false,
CRLF = '\r\n';
//
// WebSocket requests must have the `GET` method and
// the `upgrade:websocket` header
//
if (req.method !== 'GET' || req.headers.upgrade.toLowerCase() !== 'websocket') {
//
// This request is not WebSocket request
//
return socket.destroy();
}
//
// Helper function for setting appropriate socket values:
// 1. Turn of all bufferings
// 2. For server set KeepAlive
// 3. For client set encoding
//
function _socket(socket, keepAlive) {
socket.setTimeout(0);
socket.setNoDelay(true);
if (keepAlive) {
if (socket.setKeepAlive) {
socket.setKeepAlive(true, 0);
}
else if (socket.pair.cleartext.socket.setKeepAlive) {
socket.pair.cleartext.socket.setKeepAlive(true, 0);
}
}
else {
socket.setEncoding('utf8');
}
}
//
// Setup the incoming client socket.
//
_socket(socket);
//
// On `upgrade` from the Agent socket, listen to
// the appropriate events.
//
function onUpgrade (reverseProxy, proxySocket) {
if (!reverseProxy) {
proxySocket.end();
socket.end();
return;
}
//
// Any incoming data on this WebSocket to the proxy target
// will be written to the `reverseProxy` socket.
//
proxySocket.on('data', listeners.onIncoming = function (data) {
if (reverseProxy.incoming.socket.writable) {
try {
self.emit('websocket:outgoing', req, socket, head, data);
reverseProxy.incoming.socket.write(data);
}
catch (ex) {
reverseProxy.incoming.socket.end();
proxySocket.end();
}
}
});
//
// Any outgoing data on this Websocket from the proxy target
// will be written to the `proxySocket` socket.
//
reverseProxy.incoming.socket.on('data', listeners.onOutgoing = function(data) {
try {
self.emit('websocket:incoming', reverseProxy, reverseProxy.incoming, head, data);
proxySocket.write(data);
}
catch (ex) {
proxySocket.end();
socket.end();
}
});
//
// Helper function to detach all event listeners
// from `reverseProxy` and `proxySocket`.
//
function detach() {
proxySocket.removeListener('end', listeners.onIncomingClose);
proxySocket.removeListener('data', listeners.onIncoming);
reverseProxy.incoming.socket.removeListener('end', listeners.onOutgoingClose);
reverseProxy.incoming.socket.removeListener('data', listeners.onOutgoing);
}
//
// If the incoming `proxySocket` socket closes, then
// detach all event listeners.
//
proxySocket.on('end', listeners.onIncomingClose = function() {
reverseProxy.incoming.socket.end();
detach();
// Emit the `end` event now that we have completed proxying
self.emit('websocket:end', req, socket, head);
});
//
// If the `reverseProxy` socket closes, then detach all
// event listeners.
//
reverseProxy.incoming.socket.on('end', listeners.onOutgoingClose = function() {
proxySocket.end();
detach();
});
};
function getPort (port) {
port = port || 80;
return port - 80 === 0 ? '' : ':' + port
}
//
// Get the protocol, and host for this request and create an instance
// of `http.Agent` or `https.Agent` from the pool managed by `node-http-proxy`.
//
var agent = this.target.agent,
protocolName = this.target.https ? 'https' : 'http',
portUri = getPort(this.source.port),
remoteHost = options.host + portUri;
//
// Change headers (if requested).
//
if (this.changeOrigin) {
req.headers.host = remoteHost;
req.headers.origin = protocolName + '://' + remoteHost;
}
//
// Make the outgoing WebSocket request
//
outgoing.host = this.target.host;
outgoing.port = this.target.port;
outgoing.method = 'GET';
outgoing.path = req.url;
outgoing.headers = req.headers;
var reverseProxy = agent.appendMessage(outgoing);
//
// On any errors from the `reverseProxy` emit the
// `webSocketProxyError` and close the appropriate
// connections.
//
function proxyError (err) {
reverseProxy.end();
if (self.emit('webSocketProxyError', req, socket, head)) {
return;
}
socket.end();
}
//
// Here we set the incoming `req`, `socket` and `head` data to the outgoing
// request so that we can reuse this data later on in the closure scope
// available to the `upgrade` event. This bookkeeping is not tracked anywhere
// in nodejs core and is **very** specific to proxying WebSockets.
//
reverseProxy.agent = agent;
reverseProxy.incoming = {
request: req,
socket: socket,
head: head
};
//
// If the agent for this particular `host` and `port` combination
// is not already listening for the `upgrade` event, then do so once.
// This will force us not to disconnect.
//
// In addition, it's important to note the closure scope here. Since
// there is no mapping of the
//
if (!agent._events || agent._events['upgrade'].length === 0) {
agent.on('upgrade', function (_, remoteSocket, head) {
//
// Prepare the socket for the reverseProxy request and begin to
// stream data between the two sockets. Here it is important to
// note that `remoteSocket._httpMessage === reverseProxy`.
//
_socket(remoteSocket, true);
onUpgrade(remoteSocket._httpMessage, remoteSocket);
});
}
//
// If the reverseProxy connection has an underlying socket,
// then execute the WebSocket handshake.
//
if (typeof reverseProxy.socket !== 'undefined') {
reverseProxy.socket.on('data', function handshake (data) {
//
// Ok, kind of harmfull part of code. Socket.IO sends a hash
// at the end of handshake if protocol === 76, but we need
// to replace 'host' and 'origin' in response so we split
// data to printable data and to non-printable. (Non-printable
// will come after double-CRLF).
//
var sdata = data.toString();
// Get the Printable data
sdata = sdata.substr(0, sdata.search(CRLF + CRLF));
// Get the Non-Printable data
data = data.slice(Buffer.byteLength(sdata), data.length);
if (self.https && !self.target.https) {
//
// If the proxy server is running HTTPS but the client is running
// HTTP then replace `ws` with `wss` in the data sent back to the client.
//
sdata = sdata.replace('ws:', 'wss:');
}
try {
//
// Write the printable and non-printable data to the socket
// from the original incoming request.
//
self.emit('websocket:handshake', req, socket, head, sdata, data);
socket.write(sdata);
socket.write(data);
}
catch (ex) {
//
// Remove data listener on socket error because the
// 'handshake' has failed.
//
reverseProxy.socket.removeListener('data', handshake);
return proxyError(ex);
}
// Catch socket errors
socket.on('error', proxyError);
//
// Remove data listener now that the 'handshake' is complete
//
reverseProxy.socket.removeListener('data', handshake);
});
}
reverseProxy.on('error', proxyError);
try {
//
// Attempt to write the upgrade-head to the reverseProxy request.
//
reverseProxy.write(head);
}
catch (ex) {
return proxyError(ex);
}
//
// If we have been passed buffered data, resume it.
//
if (buffer && !errState) {
buffer.resume();
}
};
...@@ -81,7 +81,9 @@ util.inherits(ProxyTable, events.EventEmitter); ...@@ -81,7 +81,9 @@ util.inherits(ProxyTable, events.EventEmitter);
// Sets the host-based routes to be used by this instance. // Sets the host-based routes to be used by this instance.
// //
ProxyTable.prototype.setRoutes = function (router) { ProxyTable.prototype.setRoutes = function (router) {
if (!router) throw new Error('Cannot update ProxyTable routes without router.'); if (!router) {
throw new Error('Cannot update ProxyTable routes without router.');
}
this.router = router; this.router = router;
......
var RoutingProxy = exports.RoutingProxy = function () {
};
\ No newline at end of file
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