Every Transactional Email webhook uses the same general data format, regardless of the event type. The webhook request is a standard POST request with a single parameter (currently) -
There are three types of webhooks that Transactional Email currently POSTs: Message webhooks (such as when a message is sent, opened, clicked, rejected, deferred, or bounced), Sync webhooks, and Inbound webhooks.
mandrill_events parameter contains a JSON-encoded array of webhook events, up to a maximum of 1000 events. Each element in the array is a single event, such as an open, click, or blacklist sync event. For examples of each type of event and a description of the keys, select the type of events you'll be processing:
- Message events (send, deferral, hard-bounce, soft-bounce, open, click, spam, unsub, reject)
- Sync events (safelist or denylist sync)
- Inbound messages
If your webhook URL is down or can't accept requests, see how Transactional Email handles that here.
Only changes which remove or modify the expected behavior of existing parameters are considered backwards-incompatible. As a result, new keys may be added for webhooks without advance notice or versioning.