作者:RobanLee

原创文章,转载请注明: 萝卜李 http://www.robanlee.com

源码在这里: https://github.com/robanlee123/RobCron

时间有限,就不详细注释,有问题或者意见欢迎@我,也欢迎大家批评指正.

本文所必须的一些资料如下:

1. NODEJS ==> 可以去NODEJS.ORG下载最新的源码.
2. Redis ==> Redis.io
3. KUE ==> Nodejs的一个开源队列系统
4. NODE-SCHEDULE ==> NODEJS 一个开源调度系统

废话不多说,先来介绍任务的流程:

1. NODEJS或者PHP或者其他语言 写入REDIS 一个计划任务, 比如每分钟做某件事,这里就用SAYHELLO来代替好了
2. 使用NODEJS读取这个任务,并将它转换为NODE的调度任务(node-schedule 来完成)
3. 调度器[node-schedule]根据设定的规则来分发任务.
4. KUE接受任务,并且加入列队,执行.
5. DONE

STEP1: 创建一个任务

/*** Add task* @author Robanlee@gmail.com*///加载函数,集中加载一些LIB,这个源码请参照最后的附属文件
var loader = require('./loader');  function addTask(opts){new loader(this); //默认设置this.opts = {keyIDs:'schedule:job:ids',keyLists:'schedule:job:list',keyJob:'schedule:job:'}//合并配置,类似JQUERY: extendthis.mergeParams(opts);
};//Merge options
addTask.prototype.mergeParams = function ( param ){if(undefined === this.opts ) {return false;}for(var x in param) { if(param[x] != undefined && '' != param[x]) {this.opts[x] = param[x];}}
};//添加数据方法
addTask.prototype.pushData = function ( data ){ if(undefined == data ) {console.log('--ERROR:data is null');return false;}this.getIncr.call(this,function(response,obj){var id = response;obj.redisClient.rpush(obj.opts.keyLists,id,function(err,response){if(err) throw err;});data.id = id;var m = obj.redisClient.multi();for(var x in data) {m.hset( obj.opts.keyJob+id,x,data[x] );}m.exec(function(err,response){if(err) throw err; console.log('[info] Task: ['+data.name+'] has been set successful!');});   });
};//获取REDIS目前的自增ID
addTask.prototype.getIncr = function (callBack){var obj = this; this.redisClient.incr(this.opts.keyIDs,function(err,response){console.log("[info] Current id is : " + response);callBack(response, obj);});
};

加载这个lib 写入一个DEMO:

var data = { 'name':'taskDemo','created':Date.now(),'state':1,'type':'untitled','rule':'*/1 * * * *'  //这个任务规则可以为CRONTAB的规则,这个表示每分钟执行一次
};var job = new addTask();
job.pushData(data);

执行这个脚本,如果一切正常,你会看到如下信息:

NODEJS 输出:

REDIS:

接下来就是获取数据,并且转换为调度任务了,

源码:

var loader = require('./loader');
var taskLog = require("./TaskLog");function scheduleTask(){new loader(this); this.opts = {keyIDs:'schedule:job:ids',keyLists:'schedule:job:list',keyJob:'schedule:job:'}this.task = {taskDemo:undefined};//监听取消任务操作this.listenCancel();
};scheduleTask.prototype.setScheduleTask = function (data,obj){ this.task[data.name] =  this.libs['node-schedule'].scheduleJob(data.rule,function(){obj.setQueue(data);console.log('[info] Task :' + data.name + ' has been set in queue!');});};scheduleTask.prototype.setQueue = function (datas){var jobs = this.libs.kue.createQueue(); jobs.create(datas.name,{'name:':datas.name,'state':1}).save();console.log("[info] Task ["+datas.name+"] has been queued!");this.setLog(datas);
};scheduleTask.prototype.setLog = function (responseData){var logData = {jobid:responseData.id,name:responseData.name,result:1};new taskLog(logData);console.log("[info] Task has been loged");
};scheduleTask.prototype.getJob = function (){this.getJobIndex.call(this,function(response,obj){for(var x in response ) {obj.redisClient.hgetall(obj.opts.keyJob+response[x],function(err,data){console.log("[info] Task:["+data.name+"] has been loaded!");obj.setScheduleTask(data, obj);});}});
};scheduleTask.prototype.getJobIndex = function(callBack){//Read tasks from <list schedule:job:list>var o = this;this.redisClient.lrange(this.opts.keyLists,0,-1,function(err,response){if(err) throw err;callBack(response, o);});
};scheduleTask.prototype.listenCancel = function (){var job = this.libs.kue.createQueue();var that = this;job.process('cancelJob',function(data,done){  that.task[data.data.data].cancel();console.log('[info] Task: '+data.data.data + ' has been canceled') ;done();});
}

执行代码:

var x = new scheduleTask();
x.getJob();

等待一分钟后,NODEJS控制台会输出(这个任务在没有取消的情况下,每分钟都会执行):

第二分钟:

REDIS 现在的数据:

这个数据中增加了KUE的一些任务, q:job:[]:inactive 这个就标识任务还未被执行,执行后的任务状态有

complete active failed delay 四种

至此,就只剩下执行任务的步骤了

var loader = require('./loader');function execTask(){new loader(this); var job = this.libs.kue.createQueue();job.process('taskDemo',function(data,done){console.log('[info] Task:'+data.type+'#'+data.id+' has been executed successful!');//DONE之前可以做你想要做的事情done(); //千万别忘记调用此方法});}//添加一个取消定时任务的KUE任务
execTask.prototype.addCancelJob = function (){var job =this.libs.kue.createQueue();job.create('cancelJob', {data:'taskDemo'}).save();console.log('[info] Task: cancelJob has been send!');
}

执行这个脚本:

var et = new execTask();//取消定时任务
et.addCancelJob();

执行后会有2个结果

1. 程序会执行当前列队里的任务.

2. 定时任务会被取消,下一分钟后任务不会再由SCHEDULE分配

任务执行结果:

取消任务的回应:

注意最后一行…