Webhooks

What is the meaning of webhooks?

Webhooks are one of the two ways in which your applications can interact and communicate with each other - the other way is known as polling. Polling involves asking for information whenever you need it, but with webhooks, you get information in the form of new messages as soon as the other app gets it.

Webhooks are essentially messages that are automatically sent by applications whenever an event occurs. They contain messages or payloads and are sent to unique webhook URLs (which could be considered to be the app's phone number or address).

Webhooks are pretty much always a quicker way of getting data than polling and there is less effort required on your behalf. They are essentially event-driven APIs. You could say that webhooks are an event-driven API design pattern that makes it possible for you to develop an application that responds to events as they occur.

The whole purpose of webhooks is that instead of needing of keeping on requesting data on a repetitive basis, the application that receives the data can just relax while the other application sends the data required whenever an event takes place.

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The definition of webhooks

In the words of Jeff Lindsay, who was one of the first folks to conceptualize webhooks, webhooks are essentially "user-defined callbacks made with HTTP".

They are data and executable commands sent from one application to another app via HTTP rather than the command line in your computer and are formatted XML, JSON, or form-encoded serialization. They are known as webhooks due to the fact that they are software hooks (which are functions that run when an event occurs) that work over the web.

Every user of an app receives a unique, randomly generated URL to which they can send webhook data. They could also be secured using a key or a signature.

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What are webhooks used for?

Webhooks are also known as web callbacks or HTTP push APIs. They are used to let apps provide other applications with information in real-time. They are utilized to deliver data to other applications as events occur, which makes it possible for people to get data immediately in real-time, without any delays.

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Webhook testers - Requestbin and Postman

Requestbin and Postman offer you easy ways to experiment with webhooks without breaking anything.

Requestbin makes it possible for you to create a webhooks URL and send data to it to check how it gets recognized. To do that, you'd need to click on 'Create a RequestBin' and then proceed to copy the URL that you are provided. You would need to have a Pipedream account in order to view and use a URL.

Now you'd need to serialize some data in the form encoded style, open up another tab, paste your RequestBin URL in the URL bar, add a question mark (?) at the end, and proceed to paste your serialized data there. Hit 'enter' and you'll receive a message - success:true.

Now refresh your RequestBin tab, and you'll be able to find the data listed at the bottom.

After that, you can POST requests in Terminal or from your own app's code. Postman makes it possible for you to create custom HTTP requests so that you can create customized data to a webhooks URL. Add the URL and pick the HTTP request method that you intend to use (GET, POST, PUT, etc.). Now add the body data. (Quick tip - POST tends to be the best option for most webhook integrations.)

This will make it possible for you to share way more complex and detailed requests to your webhook URL without needing to use additional code.

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Webhooks VS API - what is the difference?

An API (Application Programming Interface) makes it possible for two-way communication driven by requests between software to occur. Webhooks, on the other hand, are essentially lightweight APIs that power one-way sharing of data and are triggered by events. APIs and webhooks together make it possible for applications to share data and functionality, thus allowing the web to be more than just the sum of its parts.

They both enable different software systems to work together and share information with each other.

APIs are like portals that make it possible for information and functionality to be shared among two software services. There are several types and categories of APIs available, but to put it simply, APIs are pretty much the most common way for different software systems to share information and work together with each other.

Webhooks can be seen as APIs that are driven by events instead of requests. Rather than one application needing to make a request to another one and wait for a response, webhooks allow programs to send new messages with data to each other as soon as specific events occur.

Due to the fact that the interaction is initiated by the application that sends the data rather than the one that receives it, webhooks are also called 'reverse APIs'.

The biggest differences between webhooks are APIs are:

APIs are driven by requests while webhooks are driven by events.
APIs facilitate two-way communication while webhooks only facilitate one-way communication
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How do webhooks work?

Webhooks are user-defined HTTP callbacks (tiny code snippets linked to a web application) that get triggered by specific events. As soon as the trigger event occurs in the source site, the webhook becomes aware of the event, gathers the data, and sends it over to the URL defined by you as an HTTP request. It is even possible for you to set webhooks up such that an event occurring on one site triggers an action in another site.

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Where can you find webhooks in github?

If you want to set up a webhook, you'll need to head to the settings page of your repository or organization. Once you're there, you can click on 'Webhooks' and hit 'Add webhook'.

You could even choose to build and manage a webhook using the Webhooks API.

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