What is a webhook?

A webhook is an automated, event-driven way for one application to send real-time data to another application via an HTTP request, acting like a "reverse API" or a digital doorbell that pushes information when something happens, rather than the receiving app constantly asking for it. It uses a unique URL Callback URL to deliver a data package (payload) when a specific event occurs, like a payment, order, or update, enabling instant communication and workflow automation between systems

How it works:

1. Event Trigger: An action happens in a source application (e.g., a new user signs up).

2. Data Collection: The source app gathers relevant data about the event (the payload)

3. HTTP Request: The source app automatically sends this payload as an HTTP POST request to a pre-configured webhook URL provided by the destination app.

4. Data Reception: The destination app receives the request at its unique URL and processes the data, often responding with a status code (like 200 OK) to confirm receipt

Key characteristics:

• Event-Driven: Triggers on specific events, not just when asked.

• Real-Time: Delivers data instantly, unlike polling (repeatedly checking).

• Automated: Reduces manual effort and constant API calls.

• Lightweight: A simpler, focused communication method than full APIs.

Common examples:

• Getting an instant SMS from your bank after a transaction.

• A payment processor sending order details to your CRM or accounting software.

• A hosting provider rebuilding a website automatically when content changes.

• Receiving Slack notifications for specific GitHub activity

A webhook is a mechanism for one application to automatically send data to another in real time when a specific event occurs, via an HTTP callback.

Detailed Explanation

• A webhook is essentially a user-defined HTTP callback.

• Instead of one system polling another for updates, webhooks push data automatically when an event occurs.

• They are widely used in modern web applications to enable event-driven communication between services.

How Webhooks Work

1. You register a webhook URL (an endpoint in your application).

2. An event occurs in the source system (e.g., a new order, a Git commit, a payment).

3. The source system sends an HTTP request (usually POST) with event data to your webhook URL.

4. Your application processes the data and takes action (e.g., update a database, trigger a workflow).

Example

• Suppose you build a custom app to track Amazon orders.

• Instead of constantly checking Amazon’s API, you register a webhook URL.

• When a new order is placed, Amazon pushes the order details to your app via the webhook.

Webhook vs Polling

Considerations

• Security: Always validate incoming webhook requests (e.g., signatures, tokens).

• Reliability: Handle retries in case of network failures.

• Scalability: Ensure your webhook endpoint can handle bursts of events.

In short: A webhook is a real-time, event-driven communication mechanism that lets applications talk to each other automatically via HTTP callbacks, making systems more efficient and responsive.

Would you like me to also show you how to implement a webhook in .NET Core with a simple code example?

As per Wikipedia, "In web development, a webhook is a method of augmenting or altering the behavior of a web page or web application with custom callbacks. These callbacks may be maintained, modified, and managed by third-party users who need not be affiliated with the originating website or application".

In simple words, "A webhook is a technique used in web development that allows one system to send real-time data to another system whenever a particular event occurs. Unlike traditional APIs where the user needs to periodically request data, webhooks automatically push data when an event happens, enabling more efficient and immediate data transfer".

Webhooks are often implemented through HTTP POST requests sent to a specified URL. For instance, when a user signs up for a service, a webhook can be set up to notify another application about the new registration by sending a POST request with relevant data to the specified endpoint.

Webhooks are commonly used in various applications including payment systems, where a service might need to be notified about payment status changes, or in continuous integration/continuous deployment (CI/CD) workflows, where a webhook triggers a new build process upon code changes. They allow for seamless integration and communication between different systems and services.

To know more about Webhook, visit:

• https://www.c-sharpcorner.com/article/webhooks-in-net/
• https://learn.microsoft.com/en-us/aspnet/webhooks/
• https://en.wikipedia.org/wiki/Webhook
• https://www.redhat.com/en/topics/automation/what-is-a-webhook

Thanks!

!! Happy Learning !!

This is a method for one application to automatically send real-time information to another application when a specific event occurs.

A webhook in terms of a Web API is actually the way an application can send real-time information to another system over the web. Instead of having an application send a request to an API to fetch data, the API simply sends data to the application when certain events or triggers occur.

For example you're using a payment gateway API that supports webhooks. Now you configure a webhook URL in your application where the gateway will send notifications when a payment is successful. Once the payment occurs, the gateway sends an HTTP request to your webhook URL, and your application processes the payment and updates the order status.

Characteristics of Webhooks:

Real-time: Webhooks are activated once specific events occur and can send data in real-time.
Push mechanism: the actual data is pushed to your application system, so no refresh on the API to actually know if something changed.
Event-based: Most often, webhooks are attached to specific events within an API such as posting a new message, order placed, or updated item.

For more details check the below links.
https://www.c-sharpcorner.com/article/webhooks-in-net/
https://www.techtarget.com/searchapparchitecture/tip/Webhooks-explained-simply-and-how-they-differ-from-an-API
https://www.mparticle.com/blog/apis-vs-webhooks/
https://www.redhat.com/en/topics/automation/what-is-a-webhook

A webhook is a way for one application to send real-time data to another whenever a specific event occurs. It’s essentially a user-defined HTTP callback. When the event happens, the source application makes an HTTP request (often a POST request) to a URL specified by the user, allowing for immediate updates and interactions without continuous polling

1. Real-time communication: Webhooks provide instant notifications, which can be more efficient than periodic polling.
2. Event-driven: They are triggered by specific events, such as a new user signing up or a payment being processed.
3. Customizable: Users can define what events trigger the webhook and the URL that receives the data.