metamaps--metamaps/realtime/node_modules/socket.io/lib/parser.js

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/*!
* socket.io-node
* Copyright(c) 2011 LearnBoost <dev@learnboost.com>
* MIT Licensed
*/
/**
* Module dependencies.
*/
/**
* Packet types.
*/
var packets = exports.packets = {
'disconnect': 0
, 'connect': 1
, 'heartbeat': 2
, 'message': 3
, 'json': 4
, 'event': 5
, 'ack': 6
, 'error': 7
, 'noop': 8
}
, packetslist = Object.keys(packets);
/**
* Errors reasons.
*/
var reasons = exports.reasons = {
'transport not supported': 0
, 'client not handshaken': 1
, 'unauthorized': 2
}
, reasonslist = Object.keys(reasons);
/**
* Errors advice.
*/
var advice = exports.advice = {
'reconnect': 0
}
, advicelist = Object.keys(advice);
/**
* Encodes a packet.
*
* @api private
*/
exports.encodePacket = function (packet) {
var type = packets[packet.type]
, id = packet.id || ''
, endpoint = packet.endpoint || ''
, ack = packet.ack
, data = null;
switch (packet.type) {
case 'message':
if (packet.data !== '')
data = packet.data;
break;
case 'event':
var ev = { name: packet.name };
if (packet.args && packet.args.length) {
ev.args = packet.args;
}
data = JSON.stringify(ev);
break;
case 'json':
data = JSON.stringify(packet.data);
break;
case 'ack':
data = packet.ackId
+ (packet.args && packet.args.length
? '+' + JSON.stringify(packet.args) : '');
break;
case 'connect':
if (packet.qs)
data = packet.qs;
break;
case 'error':
var reason = packet.reason ? reasons[packet.reason] : ''
, adv = packet.advice ? advice[packet.advice] : ''
if (reason !== '' || adv !== '')
data = reason + (adv !== '' ? ('+' + adv) : '')
break;
}
// construct packet with required fragments
var encoded = type + ':' + id + (ack == 'data' ? '+' : '') + ':' + endpoint;
// data fragment is optional
if (data !== null && data !== undefined)
encoded += ':' + data;
return encoded;
};
/**
* Encodes multiple messages (payload).
*
* @param {Array} messages
* @api private
*/
exports.encodePayload = function (packets) {
var decoded = '';
if (packets.length == 1)
return packets[0];
for (var i = 0, l = packets.length; i < l; i++) {
var packet = packets[i];
decoded += '\ufffd' + packet.length + '\ufffd' + packets[i]
}
return decoded;
};
/**
* Decodes a packet
*
* @api private
*/
var regexp = /([^:]+):([0-9]+)?(\+)?:([^:]+)?:?([\s\S]*)?/;
/**
* Wrap the JSON.parse in a seperate function the crankshaft optimizer will
* only punish this function for the usage for try catch
*
* @api private
*/
function parse (data) {
try { return JSON.parse(data) }
catch (e) { return false }
}
exports.decodePacket = function (data) {
var pieces = data.match(regexp);
if (!pieces) return {};
var id = pieces[2] || ''
, data = pieces[5] || ''
, packet = {
type: packetslist[pieces[1]]
, endpoint: pieces[4] || ''
};
// whether we need to acknowledge the packet
if (id) {
packet.id = id;
if (pieces[3])
packet.ack = 'data';
else
packet.ack = true;
}
// handle different packet types
switch (packet.type) {
case 'message':
packet.data = data || '';
break;
case 'event':
pieces = parse(data);
if (pieces) {
packet.name = pieces.name;
packet.args = pieces.args;
}
packet.args = packet.args || [];
break;
case 'json':
packet.data = parse(data);
break;
case 'connect':
packet.qs = data || '';
break;
case 'ack':
pieces = data.match(/^([0-9]+)(\+)?(.*)/);
if (pieces) {
packet.ackId = pieces[1];
packet.args = [];
if (pieces[3]) {
packet.args = parse(pieces[3]) || [];
}
}
break;
case 'error':
pieces = data.split('+');
packet.reason = reasonslist[pieces[0]] || '';
packet.advice = advicelist[pieces[1]] || '';
}
return packet;
};
/**
* Decodes data payload. Detects multiple messages
*
* @return {Array} messages
* @api public
*/
exports.decodePayload = function (data) {
if (undefined == data || null == data) {
return [];
}
if (data[0] == '\ufffd') {
var ret = [];
for (var i = 1, length = ''; i < data.length; i++) {
if (data[i] == '\ufffd') {
ret.push(exports.decodePacket(data.substr(i + 1, length)));
i += Number(length) + 1;
length = '';
} else {
length += data[i];
}
}
return ret;
} else {
return [exports.decodePacket(data)];
}
};