lynx-cron

Cron module for the Lynx framework.

This module adds a cron subsystem to your lynx application, wrapping the usual cron libraries (more specifically https://github.com/kelektiv/node-cron).

Each cron job shall be a working GET endpoint, that will be executed at a certain time, using the usual cron job specification.

A job is considered successfully completed if its status code is 200. Usual http errors code, like 400 or 500, can be used to signal an error. In this case, the job will be rescheduled, until the maximum number of retry is reached, or if its status code is 200.

Notes

This CronModule implementation can be only used in an environment where the lynx application is executed as a single instance. Otherwise, each job could be executed more then once. In such environment, a more sophisticated cron module is recommended.

Installation

npm install --save lynx-cron

Dependencies

Only the lynx-framework, of course :D

Usage

In your main app file:

import CronModule from "lynx-cron";
...

let myConfig = new ConfigBuilder(__dirname).build();

const app = new App(myConfig, [new CronModule()]);
app.startServer(port);

The CronModule can be also be easily accessed as a singleton:

let cronModule = CronModule.get();

A job can be registered using the addJob method:

cronModule.addJob('00 30 11 * * 1-5', 'http://localhost:3000/jobs/invoices?authkey=123123123');

End, in the same way, a job can be deleted using the removeJob method:

cronModule.removeJob('00 30 11 * * 1-5', 'http://localhost:3000/jobs/invoices?authkey=123123123');

By default, each registered job is saved in the db, using the CronJobEntity. In this way, a cron job can survive multiple crash or restart of the lynx app.