Web Scraping & Bots · Leçon

Planifier des tâches de base

Mettez en œuvre des mécanismes simples de planification pour exécuter vos robots à intervalles précis et assurer une automatisation continue.

Planifier des tâches de base est une leçon Web Scraping & Bots gratuite sur CoddyKit. Ceci est la leçon 3 sur 4. Tu peux lire la leçon complète ci-dessous gratuitement — puis la pratiquer en direct dans le navigateur avec un éditeur de code intégré et un tuteur IA 24/7. Elle fait partie du parcours d'apprentissage Web Scraping & Bots, et ta progression se synchronise sur le web et l'application CoddyKit. Le cours Web Scraping & Bots comprend 4 leçons au total.

Certaines parties de cette leçon n'ont pas encore été traduites et s'affichent en anglais.

Why Schedule Your Bot?

Ever wished your bot could run itself without you pressing "Go"? That's where scheduling comes in!

Scheduling allows your bot to perform tasks automatically at specific times or intervals. This is super useful for:

Monitoring: Checking a website every hour for updates.
Data Collection: Scraping news articles daily.
Notifications: Sending alerts when a price changes.

Let's learn how to make your bot work on its own schedule.

Pausing Your Bot with `time.sleep()`

The simplest way to introduce a delay in your Python bot is using the time.sleep() function. It pauses your program for a specified number of seconds.

This is great for waiting between requests to avoid overwhelming a server, or just to slow things down.

Try this simple example:

import time

def main():
    print("Starting task...")
    time.sleep(2) # Pause for 2 seconds
    print("Task finished after delay.")

if __name__ == "__main__":
    main()

Making Tasks Repeat

To make your bot do something repeatedly, you can combine time.sleep() with a while loop. This creates a basic, continuous operation.

Your bot will execute the task, pause, and then repeat indefinitely (or until you stop it).

Be careful with infinite loops in real bots – you'll need a way to stop them!

import time

def main():
    counter = 0
    while counter < 3: # Run 3 times for demo
        print(f"Bot is running task {counter + 1}...")
        time.sleep(3) # Wait 3 seconds
        counter += 1
    print("Bot finished its scheduled runs.")

if __name__ == "__main__":
    main()

When `time.sleep()` Isn't Enough

While a while loop with time.sleep() works for simple repetition, it has limitations:

Blocking: The entire program pauses. If you have other things to do, they also stop.
Fixed Intervals: It's hard to schedule tasks at specific clock times (e.g., "every day at 9 AM") rather than just "every X seconds."
Complexity: Managing multiple, different schedules becomes messy.

For more sophisticated scheduling, we need a better tool.

Meet the `schedule` Library

For more flexible and readable scheduling within Python, the schedule library is a popular choice. It lets you define tasks and their schedules in a very intuitive way.

First, you need to install it:

pip install schedule

Once installed, you can tell it exactly when to run your functions.

Scheduling a Task for the Future

The schedule library makes it easy to run a function after a certain delay. You tell it how often, and what function to call.

Let's create a simple function and schedule it to run once after a few seconds.

import schedule
import time

def my_task():
    print("This task ran as scheduled!")

def main():
    print("Scheduling task to run in 5 seconds...")
    schedule.every(5).seconds.do(my_task)

    # This loop keeps the scheduler running
    start_time = time.time()
    while True:
        schedule.run_pending()
        time.sleep(1) # Check every second
        # For this demo, let's stop after 6 seconds
        if time.time() > start_time + 6:
            break
    print("Scheduler stopped.")

if __name__ == "__main__":
    main()

Setting Up Recurring Tasks

The real power of schedule comes from defining recurring tasks. You can schedule tasks to run every second, minute, hour, day, or even specific days of the week.

Here are some examples of how you can define recurring schedules:

schedule.every(10).minutes.do(job)
schedule.every().hour.do(job)
schedule.every().day.at("10:30").do(job)
schedule.every().monday.do(job)
schedule.every().wednesday.at("13:15").do(job)

It's very flexible!

Running Your Scheduled Bot

After you've defined your scheduled tasks, you need a way for the schedule library to constantly check if any tasks are due to run. This is done with a simple loop.

The schedule.run_pending() function checks for tasks, and time.sleep() ensures your bot isn't constantly busy checking.

import schedule
import time

def scrape_news():
    print("Scraping news headlines...")
    # In a real bot, this would fetch data
    print("News scraped at", time.strftime("%H:%M:%S"))

def check_price_alert():
    print("Checking for price drops...")
    # In a real bot, this would check prices
    print("Price check at", time.strftime("%H:%M:%S"))

def main():
    print("Bot is starting. Tasks scheduled.")
    schedule.every(5).seconds.do(scrape_news)
    schedule.every(10).seconds.do(check_price_alert)

    # Main loop to run pending tasks
    start_time = time.time()
    while True:
        schedule.run_pending()
        time.sleep(1) # Check every second
        if time.time() - start_time > 25: # Run for 25 seconds for demo
            break
    print("Bot finished its scheduled operations for the demo.")

if __name__ == "__main__":
    main()

Beyond In-Bot Scheduling

While the schedule library is great for simple, in-process scheduling, large-scale or mission-critical bots often use external scheduling tools.

Cron (Linux/macOS): A powerful command-line utility for scheduling tasks.
Task Scheduler (Windows): A built-in tool for automating tasks.
Cloud Schedulers: Services like AWS EventBridge or Google Cloud Scheduler for cloud-based bots.

These tools can start your Python script itself, offering more robustness and system-level control.

Schedule It!

You've learned about different ways to schedule tasks for your bot. Now, let's test your understanding!

Recap: Scheduling Your Bots

Great job! You've mastered the basics of scheduling in Python. We covered:

Using time.sleep() for simple pauses and basic loops for repetition.
The limitations of simple loops for complex scheduling.
How to use the powerful schedule library for flexible task management.
The importance of the schedule.run_pending() loop.
A brief mention of external scheduling tools for production bots.

Now your bots can truly work for you, even when you're away!

Questions Fréquemment Posées

La leçon « Planifier des tâches de base » est-elle gratuite ?

Oui — le texte complet de « Planifier des tâches de base » est gratuit à lire ici sur le web. Pour la pratiquer de manière interactive (un éditeur de code intégré et un tuteur IA 24/7) et déverrouiller le reste du cours Web Scraping & Bots, passe à CoddyKit PRO. Le cours Web Scraping & Bots comprend 4 leçons au total.

Qu'est-ce que j'apprendrai dans « Planifier des tâches de base » ?

Mettez en œuvre des mécanismes simples de planification pour exécuter vos robots à intervalles précis et assurer une automatisation continue. Tu pratiques Web Scraping & Bots avec du code pratique que tu exécutes directement dans le navigateur, et un tuteur IA 24/7 répond à tes questions au fur et à mesure que tu avances dans la leçon.

Dois-je avoir de l'expérience pour commencer Web Scraping & Bots ?

Aucune expérience préalable n'est requise. Web Scraping & Bots sur CoddyKit est structuré pour les débutants jusqu'aux apprenants avancés, donc tu peux commencer ici ou depuis le début et avancer à ton rythme. Ceci est la leçon 3 sur 4.

Combien de temps prend la leçon « Planifier des tâches de base » ?

La plupart des leçons CoddyKit prennent environ 5–10 minutes. Chacune est courte et interactive, tu progresses régulièrement et tu repiques exactement où tu t'es arrêté sur le web et l'app.

Peux-tu écrire et exécuter du code dans cette leçon Web Scraping & Bots ?

Oui. Chaque leçon Web Scraping & Bots inclut un éditeur de code intégré, tu écris et exécutes du vrai code directement dans ton navigateur et tu reçois des retours IA instantanés — aucune configuration locale requise.

Toutes les leçons de ce cours

Définir les objectifs d’un robot
Automatiser l’envoi de formulaires simples
Planifier des tâches de base
Journalisation et gestion des erreurs pour les robots

← Retour à Web Scraping & Bots