The Webhooks API allows you to subscribe to events happening with your created objects (Invoices or Payouts) in Calypso. Rather than making an API call to check status of invoice or payout during processing, Calypso can send an HTTP request to an endpoint you configure. You can configure subscribed events using the endpoints detailed below.
In order to receive notifications you should send a POST request to the create webhook endpoint where you should transmit URL where you want to receive POST requests with event data from Calypso and event types or group of event types for which you need to receive notifications.
Then when one of events for which you have subscription happens, Calypso sends a POST request to the configured URL with data about the event.
You can manage your subscription using the delete webhook endpoint and the change webhook endpoint.
There is the get list of webhook subscriptions endpoint in order to get information about events and URLs you have a subscription.
If the receiving party returned an error when sending the webhook to the configured URL, Calypso will be trying to resend the webhook. The first retry will be occured in 30 seconds. The next retries will be proceeded in Fibonacci sequence: 30 s, 60 s, 90 s, 150 s, 240 s and so on. The last period of retry is 125 430 s (~ 34 hours). The last webhook will try to be resent after 125 430 s and then will be stopped. There are 19 retries in total.