document headers we send to payloads

atmos · atmos · commit a6bf28adf3db · 2014-03-11T15:12:04.000-07:00
diff --git a/content/v3/repos/hooks.md b/content/v3/repos/hooks.md
@@ -33,6 +33,16 @@ or the [PubSubHubbub API](#pubsubhubbub).
 
     POST /repos/:owner/:repo/hooks
 
+### Webhook Headers
+
+GitHub will send along a few HTTP headers to differentiate between event types and payload identifiers.
+
+Name | Description
+-----|-----------|
+`HTTP_X_GITHUB_EVENT` | The [event type](#events) that was triggered.
+`HTTP_X_GITHUB_DELIVERY` | A [guid][guid] to identify the payload and event being sent.
+`HTTP_X_GITHUB_SIGNATURE` | The value of this header is computed as the HMAC hex digest of the body, using the `secret` config option as the key.
+
 ### Parameter
 
 Name | Type | Description
@@ -197,4 +207,4 @@ Name | Type | Description
 [hub-signature]: https://github.com/github/github-services/blob/f3bb3dd780feb6318c42b2db064ed6d481b70a1f/lib/service/http_helper.rb#L77
 [pshb-secret]: http://pubsubhubbub.googlecode.com/svn/trunk/pubsubhubbub-core-0.3.html#authednotify
 [events-url]: /webhooks/#events
-[ping-event-url]: /webhooks/#ping-event
+[ping-event-url]: /webhooks/#ping-event
