nodecron

Nodecron, commonly referred to as node-cron, is a lightweight scheduling library for Node.js that enables running functions at times specified by cron expressions. It is designed to be simple and dependency-light, making it suitable for recurring tasks within a Node application, such as maintenance jobs, data synchronization, or report generation.

Overview and usage: The library exposes a schedule function that takes a cron expression, a callback, and an optional options object. The invocation returns a task object that can be controlled with start, stop, and destroy methods. Example: const cron = require('node-cron'); const task = cron.schedule('*/5 * * * *', () => { doSomething(); }, { timezone: 'UTC' }); The typical cron expression follows five fields (minute, hour, day of month, month, day of week); some implementations, including certain versions of node-cron, support an optional seconds field as well.

Expression support and behavior: Cron expressions are parsed to trigger the callback when the system time matches the schedule. The scheduler runs inside the Node.js event loop and relies on the process remaining active. It does not provide persistence across restarts, so tasks will not resume after a server reboot unless the application is started again or an external scheduler is used.

Limitations and considerations: Precision depends on the Node process performance and clock accuracy. Time zone configuration is optional and varies by version. Error handling in callbacks should be managed to avoid stopping the scheduler, and long-running tasks can delay subsequent schedules.

See also: Other cron-like schedulers for Node.js include node-schedule and Agenda.