Use cases for WebHooks in Arena

[delros]

Hi everyone,

The capability to use the webhooks is present in Arena and the respective endpoints defined in the specification. Still, I'm struggling to find any related documentation or examples for events that can be subscribed or typical use cases when and where these webhooks might be used.

I would assume that the webhooks are used by "companion" apps and/or for synchronization as per the master-slave synchronization architecture of the system, but in case if we can create a custom listener of the events, that means bespoke external "companion" apps also can be created to extend the native functionality, which looks prominent enough.

Do we have any examples of the webhooks usage or documentation about supported events and hook payloads? Could you please share any related insights regarding these capabilities?

[eveyrat]

Hi @delros,

You can configure Webhooks through the UI available at /bracket/webhook/. You can "listen" for different events (Insert, Update, Delete), on different entities (Fight, SportEvent, etc.), and get notified on the endpoint of your choice.

Arena will trigger a POST request to your endpoint.
I'd suggest creating a Test Webhook for inspecting the payload using a service like https://webhook.site

The payload is very minimal. It contains the Entity, ID and action. Then up to you to do further API calls depending on your use case:

{
  "action": "<action>",
  "entity": "<entity>",
  "id": "<entity_id>"
}

Example:

{
  "action": "update",
  "entity": "Fight",
  "id": "1eec01fa-25d8-6c3a-9bcc-5b5367a7e936"
}

The built-in master-slave sync is not using Webhooks but the purpose is to give the flexibility to anyone to integrate Arena in their own workflows.
For instance syncing with a third party app, or At UWW, we use it for CDN cache invalidation.

[delros]

That's exactly what I was interested in - /bracket/webhook/. I'm not familiar enough at the moment with Arean UI and how it operates (besides recorded videos of the workshops shared in a repo), so this guidance provides the essential direction for future investigation and learning. Thanks a lot @eveyrat

[csabavirag]

Perhaps the easiest way to get in touch with Webhooks is to create one and point to https://webhook.site/ When you visit this page, you will get a dedicated webhook where you can forward actions from Arena. Then you will see the payload being sent to the webhook listener through their web interface.

Use case can be for example:
You have a service/application querying Arena API to display/aggregate data on the fight details. To call Arena for fetching all the fights of a competition for example is resource heavy with every single request your service receives, thus you might want to "cache" the data coming from Arena to avoid unnecessary calls to the backend. Especially when the data is not changed (eg. you are in between 2 sessions, thus no fights are updated).

So to avoid this extra load (and extra delay to every single request), you can have 2 options.

1. Invalidate your cache with predefined timing. Eg. you refresh the fights in every 10, or 30 minutes. Between these refreshes, you render the front end with the cached data. That might causes delays in the displayed information. What about if your next session starts right after you refreshed your fights? In the next 10/30 minutes you will display the "previous" state until the next refresh happens. Acceptable? Take this
2. Setup a Webhook listener in your service and refresh the cache (of course if you structure your cache, you just have to refresh a part of it) whenever you receive a webhook trigger. What kind of webhook trigger you must configure? Enable the Fight insert+update+delete webhook. This way, your service will receive a message with the the ID of the fight (also the message will contain the type of the event - insert/update/delete), so you will be able to refresh this fight only from Arena. Next data rendering will contain the updated info about that fight.

Does it make sense?

[delros]

Yup, it makes perfect sense, thanks for the notes and highlights