pomelo-schedule is a schedule tool for nodejs, it's purpose is to provide a product level schedule module which is high efficient and can support large number job schedule.You can
As a schedule tool, it support two kinds of trigger: A simple trigger which use a js object and a Cron time trigger which use a Cron time string. ##Installation
npm install pomelo-schedule
##Schedule simple Job Simple job will receive a object as a trigger, which take three attributes, a JS function as object, and an object as the parameters in the job.
###Simple trigge example
//Fire 10000ms after now, and run 10 times with a 1000ms interval.
var trigger1 = {
start : Date.now() + 10000, //Start time, use the time in date object
period : 1000, //Fire interval, the precision is millisecond
count : 10 //Fire times, in this case the trigger will fire 10 times.
}
//Fire right now, and run 10 times with 1000ms interval.
var trigger2 = {
period : 1000,
count : 10
}
//Fire right now, and run for ever with 1000ms interval.
var trigger3 = {
period : 1000
}
//Fire 3000ms after right now, run only once.
var trigger4 = {
start : Date.now() + 3000;
}
//The job will fire right now, run only once.
var trigger5 = {
}
//Illegal! The 'count' attribute cannot used alone without 'period'.
var trigger6 = {
count : 10;
}
###Simple job example
var schedule = require('../lib/schedule');
var simpleJob = function(data){
console.log("run Job :" + data.name);
}
schedule.scheduleJob({start:Date.now(), period:3000, count: 10}, simpleJob, {name: 'simpleJobExample'});
##Schedule cron Job Cron job is the job that use cron trigger, it is just like the simple job, only use the cron trigger instead of simple trigger.
###Cron job example
var schedule = require('../lib/schedule');
var cronJob = function(data){
console.log("run Job :" + data.name);
}
schedule.scheduleJob("0 0/15 8 * * *", cronJob, {name:'cronJobExample'});
###Cron Trigger syntax Cron trigger has 7 fiels, the format is very like the cronTab in linux, only add a second field in the head. The fields and the boundary is as follow:
* * * * * * command to be executed - - - - - - | | | | | | | | | | | +----- day of week (0 - 6) (Sunday=0) | | | | +------- month (1 - 12) | | | +--------- day of month (1 - 31) | | +----------- hour (0 - 23) | +------------- min (0 - 59) +------------- second (0 - 59)
###Exampe of cron tirggers
"0/2 0 8 * * 6" Fire at every Satuaday at every even seconds of 08:00
"0 30 10 1 4 *" Fire at 10:30 on 1st of March
"15 15 15 10 10 *" Fire at Octorber 10th, at 15:15:15.
###Special characters Pomelo-schedule allow three kinds of spechial characters, they are '-', '/' and '.'.
-: '-' means range. For example, 1-3 in the second field means the seconds 1, 2 and 3
/: means increasement. For exapmle, 1/20 in the second field means 1, 21 and 41 second, and 1/2 means for every odd seconds as 1, 3, 5 ... ...
,: means additional values. For example, 1, 10, 15 in the second field means 1, 10 and 15 second. You can use '-', and '/' with ',', for example, 11,20-22,0/2 in the second filed means 11, 21 and all the even seconds.
##Cancel Job
var schedule = require('../lib/schedule');
var simpleJob = function(){
console.log("run simple Job ");
}
//Add a simple job and save the id
var id = schedule.scheduleJob({period: 1000}, simpleJob, {});
/**
* Do some thing else
*/
//CancelJob
schedule.cancelJob(id);
When you cancel a job, it will stop schedule immidiatelly, and delete the job.
Test