'use strict';
var net = require('net');
var tls = require('tls');
var http = require('http');
var https = require('https');
var events = require('events');
var assert = require('assert');
var util = require('util');
exports.httpOverHttp = httpOverHttp;
exports.httpsOverHttp = httpsOverHttp;
exports.httpOverHttps = httpOverHttps;
exports.httpsOverHttps = httpsOverHttps;
function httpOverHttp(options) {
var agent = new TunnelingAgent(options);
agent.request = http.request;
return agent;
}
function httpsOverHttp(options) {
var agent = new TunnelingAgent(options);
agent.request = http.request;
agent.createSocket = createSecureSocket;
agent.defaultPort = 443;
return agent;
}
function httpOverHttps(options) {
var agent = new TunnelingAgent(options);
agent.request = https.request;
return agent;
}
function httpsOverHttps(options) {
var agent = new TunnelingAgent(options);
agent.request = https.request;
agent.createSocket = createSecureSocket;
agent.defaultPort = 443;
return agent;
}
function TunnelingAgent(options) {
var self = this;
self.options = options || {};
self.proxyOptions = self.options.proxy || {};
self.maxSockets = self.options.maxSockets || http.Agent.defaultMaxSockets;
self.requests = [];
self.sockets = [];
self.on('free', function onFree(socket, host, port, localAddress) {
var options = toOptions(host, port, localAddress);
for (var i = 0, len = self.requests.length; i < len; ++i) {
var pending = self.requests[i];
if (pending.host === options.host && pending.port === options.port) {
// Detect the request to connect same origin server,
// reuse the connection.
self.requests.splice(i, 1);
pending.request.onSocket(socket);
return;
}
}
socket.destroy();
self.removeSocket(socket);
});
}
util.inherits(TunnelingAgent, events.EventEmitter);
TunnelingAgent.prototype.addRequest = function addRequest(req, host, port, localAddress) {
var self = this;
var options = mergeOptions({request: req}, self.options, toOptions(host, port, localAddress));
if (self.sockets.length >= this.maxSockets) {
// We are over limit so we'll add it to the queue.
self.requests.push(options);
return;
}
// If we are under maxSockets create a new one.
self.createSocket(options, function(socket) {
socket.on('free', onFree);
socket.on('close', onCloseOrRemove);
socket.on('agentRemove', onCloseOrRemove);
req.onSocket(socket);
function onFree() {
self.emit('free', socket, options);
}
function onCloseOrRemove(err) {
self.removeSocket(socket);
socket.removeListener('free', onFree);
socket.removeListener('close', onCloseOrRemove);
socket.removeListener('agentRemove', onCloseOrRemove);
}
});
};
TunnelingAgent.prototype.createSocket = function createSocket(options, cb) {
var self = this;
var placeholder = {};
self.sockets.push(placeholder);
var connectOptions = mergeOptions({}, self.proxyOptions, {
method: 'CONNECT',
path: options.host + ':' + options.port,
agent: false,
headers: {
host: options.host + ':' + options.port
}
});
if (options.localAddress) {
connectOptions.localAddress = options.localAddress;
}
if (connectOptions.proxyAuth) {
connectOptions.headers = connectOptions.headers || {};
connectOptions.headers['Proxy-Authorization'] = 'Basic ' +
new Buffer(connectOptions.proxyAuth).toString('base64');
}
debug('making CONNECT request');
var connectReq = self.request(connectOptions);
connectReq.useChunkedEncodingByDefault = false; // for v0.6
connectReq.once('response', onResponse); // for v0.6
connectReq.once('upgrade', onUpgrade); // for v0.6
connectReq.once('connect', onConnect); // for v0.7 or later
connectReq.once('error', onError);
connectReq.end();
function onResponse(res) {
// Very hacky. This is necessary to avoid http-parser leaks.
res.upgrade = true;
}
function onUpgrade(res, socket, head) {
// Hacky.
process.nextTick(function() {
onConnect(res, socket, head);
});
}
function onConnect(res, socket, head) {
connectReq.removeAllListeners();
socket.removeAllListeners();
if (res.statusCode !== 200) {
debug('tunneling socket could not be established, statusCode=%d',
res.statusCode);
socket.destroy();
var error = new Error('tunneling socket could not be established, ' +
'statusCode=' + res.statusCode);
error.code = 'ECONNRESET';
options.request.emit('error', error);
self.removeSocket(placeholder);
return;
}
if (head.length > 0) {
debug('got illegal response body from proxy');
socket.destroy();
var error = new Error('got illegal response body from proxy');
error.code = 'ECONNRESET';
options.request.emit('error', error);
self.removeSocket(placeholder);
return;
}
debug('tunneling connection has established');
self.sockets[self.sockets.indexOf(placeholder)] = socket;
return cb(socket);
}
function onError(cause) {
connectReq.removeAllListeners();
debug('tunneling socket could not be established, cause=%s\n',
cause.message, cause.stack);
var error = new Error('tunneling socket could not be established, ' +
'cause=' + cause.message);
error.code = 'ECONNRESET';
options.request.emit('error', error);
self.removeSocket(placeholder);
}
};
TunnelingAgent.prototype.removeSocket = function removeSocket(socket) {
var pos = this.sockets.indexOf(socket)
if (pos === -1) {
return;
}
this.sockets.splice(pos, 1);
var pending = this.requests.shift();
if (pending) {
// If we have pending requests and a socket gets closed a new one
// needs to be created to take over in the pool for the one that closed.
this.createSocket(pending, function(socket) {
pending.request.onSocket(socket);
});
}
};
function createSecureSocket(options, cb) {
var self = this;
TunnelingAgent.prototype.createSocket.call(self, options, function(socket) {
var hostHeader = options.request.getHeader('host');
var tlsOptions = mergeOptions({}, self.options, {
socket: socket,
servername: hostHeader ? hostHeader.replace(/:.*$/, '') : options.host
});
// 0 is dummy port for v0.6
var secureSocket = tls.connect(0, tlsOptions);
self.sockets[self.sockets.indexOf(socket)] = secureSocket;
cb(secureSocket);
});
}
function toOptions(host, port, localAddress) {
if (typeof host === 'string') { // since v0.10
return {
host: host,
port: port,
localAddress: localAddress
};
}
return host; // for v0.11 or later
}
function mergeOptions(target) {
for (var i = 1, len = arguments.length; i < len; ++i) {
var overrides = arguments[i];
if (typeof overrides === 'object') {
var keys = Object.keys(overrides);
for (var j = 0, keyLen = keys.length; j < keyLen; ++j) {
var k = keys[j];
if (overrides[k] !== undefined) {
target[k] = overrides[k];
}
}
}
}
return target;
}
var debug;
if (process.env.NODE_DEBUG && /\btunnel\b/.test(process.env.NODE_DEBUG)) {
debug = function() {
var args = Array.prototype.slice.call(arguments);
if (typeof args[0] === 'string') {
args[0] = 'TUNNEL: ' + args[0];
} else {
args.unshift('TUNNEL:');
}
console.error.apply(console, args);
}
} else {
debug = function() {};
}
exports.debug = debug; // for test
