Tempus.jl

Overview

Tempus.jl is a lightweight, Quartz-inspired job scheduling library for Julia. It provides an easy-to-use API for defining cron-like schedules and executing jobs at specified times.

Features

• Define jobs using cron-style scheduling expressions
• Support for job execution policies (overlap handling, retries, failure strategies)
• In-memory and file-based job storage backends
• Thread-safe scheduling with concurrency-aware execution
• Dynamic job control (enable, disable, unschedule jobs)
• Supports retry policies with exponential backoff

Installation

Tempus.jl is registered in the Julia General registry. You can install it directly from GitHub:

using Pkg
Pkg.add("Tempus")

Quick Start

Defining and Scheduling a Job

using Tempus

# Define a job that prints a message every minute
job = Tempus.Job("example_job", "* * * * *", () -> println("Hello from Tempus!"))

# Create an in-memory scheduler
scheduler = Tempus.Scheduler()

# Add the job to the scheduler
push!(scheduler, job)

# Start the scheduler (runs in a background thread)
Tempus.run!(scheduler)

Disabling and Enabling Jobs

Tempus.disable!(job)  # Prevents the job from running
Tempus.enable!(job)   # Allows it to run again

Removing a Job

Tempus.unschedule!(scheduler, job)

Using a File-Based Job Store

To persist job execution history across restarts, use a file-based store:

store = Tempus.FileStore("jobs.dat")
scheduler = Tempus.Scheduler(store)

Cron Syntax

Tempus.jl uses a familiar cron syntax for scheduling:

* * * * *  → Every minute
0 12 * * * → Every day at noon
*/5 * * * * → Every 5 minutes
# also supports second-level precision
* * * * * * → Every second

Contributing

Contributions are welcome! To contribute:

1. Fork the repository.
2. Create a new branch with your feature or bugfix.
3. Submit a pull request with your changes.

Make sure to include tests for any new functionality.

License

Tempus.jl is licensed under the MIT License.