Add docs for pretix Webinar API

doc/plugins/index.rst

@@ -16,3 +16,4 @@ If you want to **create** a plugin, please go to the
    badges
    campaigns
    digital
+   webinar

doc/plugins/webinar.rst

@@ -0,0 +1,43 @@
+pretix Webinar
+==============
+
+Fetch host URLs
+---------------
+
+.. http:get:: /api/v1/organizers/(organizer)/events/(event)/webinars/
+
+   Returns a list of all currently available webinar calls configured for an event.
+
+   **Example request**:
+
+   .. sourcecode:: http
+
+      GET /api/v1/organizers/bigevents/events/sampleconf/webinars/ HTTP/1.1
+      Host: pretix.eu
+      Accept: application/json, text/javascript
+
+   **Example response**:
+
+   .. sourcecode:: http
+
+      HTTP/1.1 200 OK
+      Vary: Accept
+      Content-Type: application/json
+
+      [
+        {
+          "name": "Webinar B – Sept. 8th, 2020",
+          "hosturl": "http://pretix.eu/demo/museum/webinar/host/a9aded3d7bd4df60/30611a34f9fee5d3/"
+        },
+        {
+          "name": "Webinar A – Sept. 8, 2020",
+          "hosturl": "http://pretix.eu/demo/museum/webinar/host/e714x7d4a4a36a04/b9cc444665xxx757/"
+        }
+      ]
+
+   :query subevent: Limit the result to the webinar(s) for a specific subevent.
+   :param organizer: The ``slug`` field of a valid organizer
+   :param event: The ``slug`` field of the event to fetch
+   :statuscode 200: no error
+   :statuscode 401: Authentication failure
+   :statuscode 403: The requested organizer or event does not exist **or** you have no permission to view it.