node-q/index.js

Q interfacing with Node.js

var libc = require("./lib/c.js");
var net = require("net");
var tls = require("tls");
var events = require("events");
var util = require("util");
var assert = require("./lib/assert.js");
var typed = require("./lib/typed.js");

function Connection(socket, nanos2date, flipTables, emptyChar2null, long2number) {
	"use strict";
	events.EventEmitter.call(this);
	this.socket = socket;
	this.nanos2date = nanos2date;
	this.flipTables = flipTables;
	this.emptyChar2null = emptyChar2null;
	this.long2number = long2number;
	this.nextRequestNo = 1;
	this.nextResponseNo = 1;
	var self = this;
	this.socket.on("end", function() {
		self.emit("end");
	});
	this.socket.on("timeout", function() {
		self.emit("timeout");
	});
	this.socket.on("error", function(err) {
		self.emit("error", err);
	});
	this.socket.on("close", function(had_error) {
		self.emit("close", had_error);
	});
}
util.inherits(Connection, events.EventEmitter);
Connection.prototype.listen = function() {
	"use strict";
	var self = this;
	this.chunk = new Buffer(0);
	this.socket.on("data", function(inbuffer) {
		var buffer,
			length, // current msg length
			o, // deserialized object
			err, // deserialize error
			responseNo;

		if (self.chunk.length !== 0) {
			buffer = new Buffer(self.chunk.length + inbuffer.length);
			self.chunk.copy(buffer);
			inbuffer.copy(buffer, self.chunk.length);
		} else {
			buffer = inbuffer;
		}
		while (buffer.length >= 8) {
			length = buffer.readUInt32LE(4);
			if (buffer.length >= length) {
				try {
					o = libc.deserialize(buffer, self.nanos2date, self.flipTables, self.emptyChar2null, self.long2number);
					err = undefined;
				} catch (e) {
					o = null;
					err = e;
				}
				if (buffer.readUInt8(1) === 2) { // MsgType: 2 := response
					responseNo = self.nextResponseNo;
					self.nextResponseNo += 1;
					self.emit("response:" + responseNo, err, o);
				} else {
					if (err === undefined && Array.isArray(o) && o[0] === "upd") {
						events.EventEmitter.prototype.emit.apply(self, o);
					} else {
						responseNo = self.nextResponseNo;
						self.nextResponseNo += 1;
						self.emit("response:" + responseNo, err, o);
					}
				}
				if (buffer.length > length) {
					buffer = buffer.slice(length);
				} else {
					buffer = new Buffer(0);
				}
			} else {
				break;
			}
		}

		self.chunk = buffer;
	});
};
Connection.prototype.auth = function(auth, cb) {
	"use strict";
	var n = Buffer.byteLength(auth, "ascii"),
		b = new Buffer(n + 2),
		self = this;
	b.write(auth, 0, n, "ascii"); // auth (username:password)
	b.writeUInt8(0x3, n); // capability byte (compression, timestamp, timespan) http://code.kx.com/wiki/Reference/ipcprotocol#Handshake
	b.writeUInt8(0x0, n+1); // zero terminated
	this.socket.write(b);
	this.socket.once("data", function(buffer) {
		if (buffer.length === 1) {
			if (buffer[0] >= 1) { // capability byte must support at least (compression, timestamp, timespan) http://code.kx.com/wiki/Reference/ipcprotocol#Handshake
				self.listen();
				cb();
			} else {
				cb(new Error("Invalid capability byte from server"));
			}
		} else {
			cb(new Error("Invalid auth response from server"));
		}
	});
};
Connection.prototype.k = function(s, cb) {
	"use strict";
	cb = arguments[arguments.length - 1];
	assert.func(cb, "cb");
	var self = this,
		payload,
		b,
		requestNo = this.nextRequestNo;
	this.nextRequestNo += 1;
	if (arguments.length === 1) {
		// Listen for async responses
		self.once("response:" + requestNo, function(err, o) {
			cb(err, o);
		});
	} else {
		assert.string(s, "s");
		if (arguments.length === 2) {
			payload = s;
		} else {
			payload = Array.prototype.slice.call(arguments, 0, arguments.length - 1);
		}
		b = libc.serialize(payload);
		b.writeUInt8(0x1, 1); // MsgType: 1 := sync
		this.socket.write(b, function() {
			self.once("response:" + requestNo, function(err, o) {
				cb(err, o);
			});
		});
	}
};
Connection.prototype.ks = function(s, cb) {
	"use strict";
	assert.string(s, "s");
	cb = arguments[arguments.length - 1];
	assert.func(cb, "cb");
	var payload,
		b;
	if (arguments.length === 2) {
		payload = s;
	} else {
		payload = Array.prototype.slice.call(arguments, 0, arguments.length - 1);
	}
	b = libc.serialize(payload);
	this.socket.write(b, function() {
		cb();
	});
};
Connection.prototype.close = function(cb) {
	"use strict";
	assert.optionalFunc(cb, "cb");
	this.socket.once("close", function() {
		if (cb) {
			cb();
		}
	});
	this.socket.end();
};

function connect(params, cb) {
	"use strict";
	var auth,
		errorcb,
		closecb,
		socket,
		error = false,
		close = false;
	if (typeof params !== "object") {
		params = {};
		if (arguments.length === 2) {
			params.unixSocket = arguments[0];
			cb = arguments[1];
		} else if (arguments.length === 3) {
			params.host = arguments[0];
			params.port = arguments[1];
			cb = arguments[2];
		} else if (arguments.length === 5) {
			params.host = arguments[0];
			params.port = arguments[1];
			params.user = arguments[2];
			params.password = arguments[3];
			cb = arguments[4];
		} else {
			throw new Error("only two, three or five arguments allowed");
		}
	}
	assert.object(params, "params");
	assert.optionalString(params.host, "params.host");
	assert.optionalNumber(params.port, "params.port");
	assert.optionalString(params.user, "params.user");
	assert.optionalString(params.password, "password");
	assert.optionalObject(params.ca, "params.ca");
	assert.optionalBool(params.socketNoDelay, "params.socketNoDelay");
	assert.optionalNumber(params.socketTimeout, "params.socketTimeout");
	assert.optionalBool(params.nanos2date, "params.nanos2date");
	assert.optionalBool(params.flipTables, "params.flipTables");
	assert.optionalBool(params.emptyChar2null, "params.emptyChar2null");
	assert.optionalBool(params.long2number, "params.long2number");
	assert.optionalString(params.unixSocket, "params.unixSocket");
	assert.optionalBool(params.useTLS, "params.useTLS");
	if (params.user !== undefined) {
		assert.string(params.password, "password");
		auth = params.user + ":" + params.password;
	} else {
		auth = "anonymous";
	}
	assert.func(cb, "cb");
	errorcb = function(err) {
		error = true;
		cb(err);
	};
	closecb = function() {
		close = true;
		cb(new Error("Connection closes (wrong auth?)"));
	};

	var socketArgs;
	if (params.useTLS) {
		socketArgs = {};
		if (params.unixSocket) {
			socketArgs.path = params.unixSocket;
		} else {
			socketArgs.port = params.port;
			socketArgs.host = params.host;
			socketArgs.ca = params.ca;
		}
	} else {
		socketArgs = [];
		if (params.unixSocket) {
			socketArgs.push(params.unixSocket);
		}
		else {
			socketArgs.push(params.port, params.host);
		}
	}
	var connectionCBfunc = function() {
		socket.removeListener("error", errorcb);
		if (error === false) {
			socket.once("close", closecb);
			var con = new Connection(socket, params.nanos2date, params.flipTables, params.emptyChar2null, params.long2number);
			con.once("error", function(err) {
				socket.removeListener("close", closecb);
				cb(err);
			});
			con.auth(auth, function() {
				socket.removeListener("close", closecb);
				if (close === false) {
					cb(undefined, con);
				}
			});
		}
	};

	if (params.useTLS) {		
		socket = tls.connect(socketArgs, connectionCBfunc);
	} else {
		socketArgs.push(connectionCBfunc);
		socket = net.connect.apply(null, socketArgs);
	}
	
	if (params.socketTimeout !== undefined) {
		socket.setTimeout(params.socketTimeout);
	}
	if (params.socketNoDelay !== undefined) {
		socket.setNoDelay(params.socketNoDelay);
	}
	socket.once("error", errorcb);
}
exports.connect = connect;

// export typed API
Object.keys(typed).forEach(function(k) {
	"use strict";
	if (/^[a-z]*$/.test(k[0])) {
		exports[k] = typed[k];
	}
});