/**
* Module dependencies.
*/
var parser = require('socket.io-parser');
var Emitter = require('component-emitter');
var toArray = require('to-array');
var on = require('./on');
var bind = require('component-bind');
var debug = require('debug')('socket.io-client:socket');
var parseqs = require('parseqs');
var hasBin = require('has-binary2');
/**
* Module exports.
*/
module.exports = exports = Socket;
/**
* Internal events (blacklisted).
* These events can't be emitted by the user.
*
* @api private
*/
var events = {
connect: 1,
connect_error: 1,
connect_timeout: 1,
connecting: 1,
disconnect: 1,
error: 1,
reconnect: 1,
reconnect_attempt: 1,
reconnect_failed: 1,
reconnect_error: 1,
reconnecting: 1,
ping: 1,
pong: 1
};
/**
* Shortcut to `Emitter#emit`.
*/
var emit = Emitter.prototype.emit;
/**
* `Socket` constructor.
*
* @api public
*/
function Socket (io, nsp, opts) {
this.io = io;
this.nsp = nsp;
this.json = this; // compat
this.ids = 0;
this.acks = {};
this.receiveBuffer = [];
this.sendBuffer = [];
this.connected = false;
this.disconnected = true;
this.flags = {};
if (opts && opts.query) {
this.query = opts.query;
}
if (this.io.autoConnect) this.open();
}
/**
* Mix in `Emitter`.
*/
Emitter(Socket.prototype);
/**
* Subscribe to open, close and packet events
*
* @api private
*/
Socket.prototype.subEvents = function () {
if (this.subs) return;
var io = this.io;
this.subs = [
on(io, 'open', bind(this, 'onopen')),
on(io, 'packet', bind(this, 'onpacket')),
on(io, 'close', bind(this, 'onclose'))
];
};
/**
* "Opens" the socket.
*
* @api public
*/
Socket.prototype.open =
Socket.prototype.connect = function () {
if (this.connected) return this;
this.subEvents();
this.io.open(); // ensure open
if ('open' === this.io.readyState) this.onopen();
this.emit('connecting');
return this;
};
/**
* Sends a `message` event.
*
* @return {Socket} self
* @api public
*/
Socket.prototype.send = function () {
var args = toArray(arguments);
args.unshift('message');
this.emit.apply(this, args);
return this;
};
/**
* Override `emit`.
* If the event is in `events`, it's emitted normally.
*
* @param {String} event name
* @return {Socket} self
* @api public
*/
Socket.prototype.emit = function (ev) {
if (events.hasOwnProperty(ev)) {
emit.apply(this, arguments);
return this;
}
var args = toArray(arguments);
var packet = {
type: (this.flags.binary !== undefined ? this.flags.binary : hasBin(args)) ? parser.BINARY_EVENT : parser.EVENT,
data: args
};
packet.options = {};
packet.options.compress = !this.flags || false !== this.flags.compress;
// event ack callback
if ('function' === typeof args[args.length - 1]) {
debug('emitting packet with ack id %d', this.ids);
this.acks[this.ids] = args.pop();
packet.id = this.ids++;
}
if (this.connected) {
this.packet(packet);
} else {
this.sendBuffer.push(packet);
}
this.flags = {};
return this;
};
/**
* Sends a packet.
*
* @param {Object} packet
* @api private
*/
Socket.prototype.packet = function (packet) {
packet.nsp = this.nsp;
this.io.packet(packet);
};
/**
* Called upon engine `open`.
*
* @api private
*/
Socket.prototype.onopen = function () {
debug('transport is open - connecting');
// write connect packet if necessary
if ('/' !== this.nsp) {
if (this.query) {
var query = typeof this.query === 'object' ? parseqs.encode(this.query) : this.query;
debug('sending connect packet with query %s', query);
this.packet({type: parser.CONNECT, query: query});
} else {
this.packet({type: parser.CONNECT});
}
}
};
/**
* Called upon engine `close`.
*
* @param {String} reason
* @api private
*/
Socket.prototype.onclose = function (reason) {
debug('close (%s)', reason);
this.connected = false;
this.disconnected = true;
delete this.id;
this.emit('disconnect', reason);
};
/**
* Called with socket packet.
*
* @param {Object} packet
* @api private
*/
Socket.prototype.onpacket = function (packet) {
var sameNamespace = packet.nsp === this.nsp;
var rootNamespaceError = packet.type === parser.ERROR && packet.nsp === '/';
if (!sameNamespace && !rootNamespaceError) return;
switch (packet.type) {
case parser.CONNECT:
this.onconnect();
break;
case parser.EVENT:
this.onevent(packet);
break;
case parser.BINARY_EVENT:
this.onevent(packet);
break;
case parser.ACK:
this.onack(packet);
break;
case parser.BINARY_ACK:
this.onack(packet);
break;
case parser.DISCONNECT:
this.ondisconnect();
break;
case parser.ERROR:
this.emit('error', packet.data);
break;
}
};
/**
* Called upon a server event.
*
* @param {Object} packet
* @api private
*/
Socket.prototype.onevent = function (packet) {
var args = packet.data || [];
debug('emitting event %j', args);
if (null != packet.id) {
debug('attaching ack callback to event');
args.push(this.ack(packet.id));
}
if (this.connected) {
emit.apply(this, args);
} else {
this.receiveBuffer.push(args);
}
};
/**
* Produces an ack callback to emit with an event.
*
* @api private
*/
Socket.prototype.ack = function (id) {
var self = this;
var sent = false;
return function () {
// prevent double callbacks
if (sent) return;
sent = true;
var args = toArray(arguments);
debug('sending ack %j', args);
self.packet({
type: hasBin(args) ? parser.BINARY_ACK : parser.ACK,
id: id,
data: args
});
};
};
/**
* Called upon a server acknowlegement.
*
* @param {Object} packet
* @api private
*/
Socket.prototype.onack = function (packet) {
var ack = this.acks[packet.id];
if ('function' === typeof ack) {
debug('calling ack %s with %j', packet.id, packet.data);
ack.apply(this, packet.data);
delete this.acks[packet.id];
} else {
debug('bad ack %s', packet.id);
}
};
/**
* Called upon server connect.
*
* @api private
*/
Socket.prototype.onconnect = function () {
this.connected = true;
this.disconnected = false;
this.emit('connect');
this.emitBuffered();
};
/**
* Emit buffered events (received and emitted).
*
* @api private
*/
Socket.prototype.emitBuffered = function () {
var i;
for (i = 0; i < this.receiveBuffer.length; i++) {
emit.apply(this, this.receiveBuffer[i]);
}
this.receiveBuffer = [];
for (i = 0; i < this.sendBuffer.length; i++) {
this.packet(this.sendBuffer[i]);
}
this.sendBuffer = [];
};
/**
* Called upon server disconnect.
*
* @api private
*/
Socket.prototype.ondisconnect = function () {
debug('server disconnect (%s)', this.nsp);
this.destroy();
this.onclose('io server disconnect');
};
/**
* Called upon forced client/server side disconnections,
* this method ensures the manager stops tracking us and
* that reconnections don't get triggered for this.
*
* @api private.
*/
Socket.prototype.destroy = function () {
if (this.subs) {
// clean subscriptions to avoid reconnections
for (var i = 0; i < this.subs.length; i++) {
this.subs[i].destroy();
}
this.subs = null;
}
this.io.destroy(this);
};
/**
* Disconnects the socket manually.
*
* @return {Socket} self
* @api public
*/
Socket.prototype.close =
Socket.prototype.disconnect = function () {
if (this.connected) {
debug('performing disconnect (%s)', this.nsp);
this.packet({ type: parser.DISCONNECT });
}
// remove socket from pool
this.destroy();
if (this.connected) {
// fire events
this.onclose('io client disconnect');
}
return this;
};
/**
* Sets the compress flag.
*
* @param {Boolean} if `true`, compresses the sending data
* @return {Socket} self
* @api public
*/
Socket.prototype.compress = function (compress) {
this.flags.compress = compress;
return this;
};
/**
* Sets the binary flag
*
* @param {Boolean} whether the emitted data contains binary
* @return {Socket} self
* @api public
*/
Socket.prototype.binary = function (binary) {
this.flags.binary = binary;
return this;
};