Introduction

When integrating two systems, developers often face a common question: should you use Webhooks or API Polling? Both approaches are used to synchronize data between systems, but they work in fundamentally different ways.

Choosing the right method can impact performance, scalability, and user experience.

What is API Polling?

API Polling is a technique where a client repeatedly sends requests to a server at regular intervals to check if new data is available.

Example

A system checks every 5 minutes for new orders using an API endpoint.

How It Works

• Client sends request to server
• Server responds with data (or no updates)
• Client repeats the process after a fixed interval

Advantages

• Simple to implement
• Full control over request timing
• No dependency on external triggers

Disadvantages

• High number of unnecessary requests
• Not real-time (delayed updates)
• Can hit API rate limits

What are Webhooks?

Webhooks are event-driven HTTP callbacks. Instead of repeatedly asking for updates, your system receives data automatically when an event occurs.

Example

When a new order is created, the server sends a POST request to your webhook URL instantly.

How It Works

• An event occurs on the server
• The server sends an HTTP POST request to a predefined URL
• Your system processes the incoming data

Advantages

• Real-time updates
• Efficient (no unnecessary requests)
• Scalable for event-driven systems

Disadvantages

• Requires public endpoint (HTTPS)
• More complex to set up
• Needs proper error handling and retries

Key Differences Between Webhooks and API Polling

Real-World Example

API Polling

A system calls an orders API every 2 minutes to check for new orders.

Webhooks

The system subscribes to an "order created" event and receives instant updates when a new order is placed.

When to Use Webhooks

• Real-time updates are required
• Event-driven architecture is preferred
• Reducing API calls is important

When to Use API Polling

• Webhooks are not available
• Periodic data synchronization is sufficient
• As a backup mechanism for missed events

Best Practice: Use Both Together

The best approach is to combine Webhooks and API Polling:

• Use Webhooks for real-time updates
• Use Polling as a backup to ensure data consistency

This hybrid approach ensures reliability and accuracy in distributed systems.

Conclusion

Webhooks and API Polling both play important roles in system integration. While Webhooks provide real-time, efficient communication, API Polling offers simplicity and reliability as a fallback mechanism.

Understanding their differences and using them appropriately can significantly improve system performance and scalability.