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Akarsh Jaiswal
Akarsh Jaiswal

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Automate Scheduled Jobs in Python Using the schedule Library: A Cron Alternative

#cronjob #python #schedule

If you’re used to setting up cron jobs on Linux to automate tasks, but want a simple, Python-native way to schedule jobs, the schedule library is an excellent alternative. It allows you to run Python functions periodically without relying on system-level cron.

In this post, I’ll show you how to:

  • Install and use the schedule library
  • Write Python scripts that run tasks on a schedule
  • Keep your jobs running continuously
  • Understand when to use schedule instead of cron

What Is the schedule Library?

schedule is a lightweight Python package designed to run jobs periodically inside your Python program. Unlike cron, which is managed by your OS, schedule lets you embed scheduling logic directly in Python.

This makes it ideal for cross-platform automation and when you want to keep everything in Python.

Installation

Install it easily with pip:

pip install schedule
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Basic Usage Example

Here’s a simple example that prints the current time every minute:

import schedule
import time
from datetime import datetime

def job():
    print(f"Task running at {datetime.now()}")

# Schedule the job every minute
schedule.every(1).minutes.do(job)

print("Scheduler started. Press Ctrl+C to exit.")

while True:
    schedule.run_pending()
    time.sleep(1)
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This script:

  • Defines a job function to run on schedule
  • Schedules it every minute
  • Enters an infinite loop that checks and runs due jobs

Scheduling Variations

schedule supports many common patterns:

schedule.every().day.at("14:00").do(job)     # Every day at 2 PM
schedule.every().hour.do(job)                 # Every hour
schedule.every().monday.do(job)                # Every Monday
schedule.every(10).seconds.do(job)            # Every 10 seconds
schedule.every(5).to(10).minutes.do(job)      # Every 5 to 10 minutes (random)
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Keeping Your Scheduled Jobs Running

Since schedule runs within your Python script, you need to ensure the script stays alive:

  • Run inside a terminal multiplexer like screen or tmux
  • Use Linux tools like systemd or supervisord to manage the script
  • Run as a background process with nohup or &
  • Dockerize your script with restart policies for resilience

Why Use schedule Over Cron?

  • Cross-platform: Works on Linux, macOS, Windows without changes
  • Python-native: Write schedules in Python rather than shell scripts
  • Dynamic: Modify schedules programmatically at runtime
  • Single process: Manage multiple jobs from one Python app

Limitations Compared to Cron

  • The Python script must be continuously running for tasks to execute
  • Lacks built-in logging, notifications, or advanced cron features
  • Not suitable for system-level task scheduling where OS guarantees execution

When Should You Use schedule?

  • When you want to keep all logic inside Python
  • For cross-platform automation without OS dependencies
  • When you want simple scheduling integrated with your Python app

For mission-critical or system-level tasks, traditional cron combined with Python scripts is still recommended.

Helpful links:

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