You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

156 lines
5.3 KiB

// Copyright Joyent, Inc. and other Node contributors.
//
// 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 net = require('net');
var util = require('util');
var EventEmitter = require('events').EventEmitter;
// New Agent code.
// The largest departure from the previous implementation is that
// an Agent instance holds connections for a variable number of host:ports.
// Surprisingly, this is still API compatible as far as third parties are
// concerned. The only code that really notices the difference is the
// request object.
// Another departure is that all code related to HTTP parsing is in
// ClientRequest.onSocket(). The Agent is now *strictly*
// concerned with managing a connection pool.
function Agent(options) {
EventEmitter.call(this);
var self = this;
self.options = options || {};
self.requests = {};
self.sockets = {};
self.maxSockets = self.options.maxSockets || Agent.defaultMaxSockets;
self.on('free', function(socket, host, port, localAddress) {
var name = host + ':' + port;
if (localAddress) {
name += ':' + localAddress;
}
if (!socket.destroyed &&
self.requests[name] && self.requests[name].length) {
self.requests[name].shift().onSocket(socket);
if (self.requests[name].length === 0) {
// don't leak
delete self.requests[name];
}
} else {
// If there are no pending requests just destroy the
// socket and it will get removed from the pool. This
// gets us out of timeout issues and allows us to
// default to Connection:keep-alive.
socket.destroy();
}
});
self.createConnection = net.createConnection;
}
util.inherits(Agent, EventEmitter);
exports.Agent = Agent;
Agent.defaultMaxSockets = 5;
Agent.prototype.defaultPort = 80;
Agent.prototype.addRequest = function(req, host, port, localAddress) {
var name = host + ':' + port;
if (localAddress) {
name += ':' + localAddress;
}
if (!this.sockets[name]) {
this.sockets[name] = [];
}
if (this.sockets[name].length < this.maxSockets) {
// If we are under maxSockets create a new one.
req.onSocket(this.createSocket(name, host, port, localAddress, req));
} else {
// We are over limit so we'll add it to the queue.
if (!this.requests[name]) {
this.requests[name] = [];
}
this.requests[name].push(req);
}
};
Agent.prototype.createSocket = function(name, host, port, localAddress, req) {
var self = this;
var options = util._extend({}, self.options);
options.port = port;
options.host = host;
options.localAddress = localAddress;
options.servername = host;
if (req) {
var hostHeader = req.getHeader('host');
if (hostHeader) {
options.servername = hostHeader.replace(/:.*$/, '');
}
}
var s = self.createConnection(options);
if (!self.sockets[name]) {
self.sockets[name] = [];
}
this.sockets[name].push(s);
var onFree = function() {
self.emit('free', s, host, port, localAddress);
}
s.on('free', onFree);
var onClose = function(err) {
// This is the only place where sockets get removed from the Agent.
// If you want to remove a socket from the pool, just close it.
// All socket errors end in a close event anyway.
self.removeSocket(s, name, host, port, localAddress);
}
s.on('close', onClose);
var onRemove = function() {
// We need this function for cases like HTTP 'upgrade'
// (defined by WebSockets) where we need to remove a socket from the pool
// because it'll be locked up indefinitely
self.removeSocket(s, name, host, port, localAddress);
s.removeListener('close', onClose);
s.removeListener('free', onFree);
s.removeListener('agentRemove', onRemove);
}
s.on('agentRemove', onRemove);
return s;
};
Agent.prototype.removeSocket = function(s, name, host, port, localAddress) {
if (this.sockets[name]) {
var index = this.sockets[name].indexOf(s);
if (index !== -1) {
this.sockets[name].splice(index, 1);
if (this.sockets[name].length === 0) {
// don't leak
delete this.sockets[name];
}
}
}
if (this.requests[name] && this.requests[name].length) {
var req = this.requests[name][0];
// If we have pending requests and a socket gets closed a new one
this.createSocket(name, host, port, localAddress, req).emit('free');
}
};
var globalAgent = new Agent();
exports.globalAgent = globalAgent;