2 files changed, 199 insertions, 0 deletions
diff --git a/node_modules/seq-queue/lib/.npmignore b/node_modules/seq-queue/lib/.npmignore
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/node_modules/seq-queue/lib/.npmignore
diff --git a/node_modules/seq-queue/lib/seq-queue.js b/node_modules/seq-queue/lib/seq-queue.js
new file mode 100644
index 0000000..f13f285
--- /dev/null
+++ b/node_modules/seq-queue/lib/seq-queue.js
@@ -0,0 +1,199 @@
+var EventEmitter = require('events').EventEmitter;
+var util = require('util');
+
+var DEFAULT_TIMEOUT = 3000;
+var INIT_ID = 0;
+var EVENT_CLOSED = 'closed';
+var EVENT_DRAINED = 'drained';
+
+/**
+ * Instance a new queue
+ *
+ * @param {Number} timeout a global timeout for new queue
+ * @class
+ * @constructor
+ */
+var SeqQueue = function(timeout) {
+	EventEmitter.call(this);
+	
+	if(timeout && timeout > 0) {
+		this.timeout = timeout;
+	} else {
+		this.timeout = DEFAULT_TIMEOUT;
+	}
+	
+	this.status = SeqQueueManager.STATUS_IDLE;
+	this.curId = INIT_ID;
+	this.queue = [];
+};
+util.inherits(SeqQueue, EventEmitter);
+
+/**
+ * Add a task into queue.
+ * 
+ * @param fn new request
+ * @param ontimeout callback when task timeout
+ * @param timeout timeout for current request. take the global timeout if this is invalid
+ * @returns true or false
+ */
+SeqQueue.prototype.push = function(fn, ontimeout, timeout) {
+	if(this.status !== SeqQueueManager.STATUS_IDLE && this.status !== SeqQueueManager.STATUS_BUSY) {
+		//ignore invalid status
+		return false;
+	}
+	
+	if(typeof fn !== 'function') {
+		throw new Error('fn should be a function.');
+	}
+	this.queue.push({fn: fn, ontimeout: ontimeout, timeout: timeout});
+
+	if(this.status === SeqQueueManager.STATUS_IDLE) {
+		this.status = SeqQueueManager.STATUS_BUSY;
+		var self = this;
+		process.nextTick(function() {
+			self._next(self.curId);
+		});
+	}
+	return true;
+};
+
+/**
+ * Close queue
+ * 
+ * @param {Boolean} force if true will close the queue immediately else will execute the rest task in queue
+ */
+SeqQueue.prototype.close = function(force) {
+	if(this.status !== SeqQueueManager.STATUS_IDLE && this.status !== SeqQueueManager.STATUS_BUSY) {
+		//ignore invalid status
+		return;
+	}
+	
+	if(force) {
+		this.status = SeqQueueManager.STATUS_DRAINED;
+		if(this.timerId) {
+			clearTimeout(this.timerId);
+			this.timerId = undefined;
+		}
+		this.emit(EVENT_DRAINED);
+	} else {
+		this.status = SeqQueueManager.STATUS_CLOSED;
+		this.emit(EVENT_CLOSED);
+	}
+};
+
+/**
+ * Invoke next task
+ * 
+ * @param {String|Number} tid last executed task id
+ * @api private
+ */
+SeqQueue.prototype._next = function(tid) {
+	if(tid !== this.curId || this.status !== SeqQueueManager.STATUS_BUSY && this.status !== SeqQueueManager.STATUS_CLOSED) {
+		//ignore invalid next call
+		return;
+	}
+	
+	if(this.timerId) {
+		clearTimeout(this.timerId);
+		this.timerId = undefined;
+	}
+	
+	var task = this.queue.shift();
+	if(!task) {
+		if(this.status === SeqQueueManager.STATUS_BUSY) {
+			this.status = SeqQueueManager.STATUS_IDLE;
+			this.curId++;	//modify curId to invalidate timeout task
+		} else {
+			this.status = SeqQueueManager.STATUS_DRAINED;
+			this.emit(EVENT_DRAINED);
+		}
+		return;
+	}
+	
+	var self = this;
+	task.id = ++this.curId;
+
+	var timeout = task.timeout > 0 ? task.timeout : this.timeout;
+	timeout = timeout > 0 ? timeout : DEFAULT_TIMEOUT;
+	this.timerId = setTimeout(function() {
+		process.nextTick(function() {
+			self._next(task.id);
+		});
+		self.emit('timeout', task);
+		if(task.ontimeout) {
+			task.ontimeout();
+		}
+	}, timeout);
+
+	try {
+		task.fn({
+			done: function() {
+				var res = task.id === self.curId;
+				process.nextTick(function() {
+					self._next(task.id);
+				});
+				return res;
+			}
+		});
+	} catch(err) {
+		self.emit('error', err, task);
+		process.nextTick(function() {
+			self._next(task.id);
+		});
+	}
+};
+
+/**
+ * Queue manager.
+ * 
+ * @module
+ */
+var SeqQueueManager = module.exports;
+
+/**
+ * Queue status: idle, welcome new tasks
+ *
+ * @const
+ * @type {Number}
+ * @memberOf SeqQueueManager
+ */
+SeqQueueManager.STATUS_IDLE = 0;
+
+/**
+ * Queue status: busy, queue is working for some tasks now
+ *
+ * @const
+ * @type {Number}
+ * @memberOf SeqQueueManager
+ */
+SeqQueueManager.STATUS_BUSY = 1;
+
+/**
+ * Queue status: closed, queue has closed and would not receive task any more 
+ * 					and is processing the remaining tasks now.
+ *
+ * @const
+ * @type {Number}
+ * @memberOf SeqQueueManager
+ */
+SeqQueueManager.STATUS_CLOSED = 2; 
+
+/**
+ * Queue status: drained, queue is ready to be destroy
+ *
+ * @const
+ * @type {Number}
+ * @memberOf SeqQueueManager
+ */
+SeqQueueManager.STATUS_DRAINED = 3;
+
+/**
+ * Create Sequence queue
+ * 
+ * @param  {Number} timeout a global timeout for the new queue instance
+ * @return {Object}         new queue instance
+ * @memberOf SeqQueueManager
+ */
+SeqQueueManager.createQueue = function(timeout) {
+	return new SeqQueue(timeout);
+};
+\ No newline at end of file