Add an order_by field to list users' media admin API. (#8978)

docs/admin_api/user_admin_api.rst

@@ -379,11 +379,12 @@ The following fields are returned in the JSON response body:
 - ``total`` - Number of rooms.
 
 
-List media of an user
-================================
+List media of a user
+====================
 Gets a list of all local media that a specific ``user_id`` has created.
-The response is ordered by creation date descending and media ID descending.
-The newest media is on top.
+By default, the response is ordered by descending creation date and ascending media ID.
+The newest media is on top. You can change the order with parameters
+``order_by`` and ``dir``.
 
 The API is::
 
@@ -440,6 +441,35 @@ The following parameters should be set in the URL:
   denoting the offset in the returned results. This should be treated as an opaque value and
   not explicitly set to anything other than the return value of ``next_token`` from a previous call.
   Defaults to ``0``.
+- ``order_by`` - The method by which to sort the returned list of media.
+  If the ordered field has duplicates, the second order is always by ascending ``media_id``,
+  which guarantees a stable ordering. Valid values are:
+
+  - ``media_id`` - Media are ordered alphabetically by ``media_id``.
+  - ``upload_name`` - Media are ordered alphabetically by name the media was uploaded with.
+  - ``created_ts`` - Media are ordered by when the content was uploaded in ms.
+    Smallest to largest. This is the default.
+  - ``last_access_ts`` - Media are ordered by when the content was last accessed in ms.
+    Smallest to largest.
+  - ``media_length`` - Media are ordered by length of the media in bytes.
+    Smallest to largest.
+  - ``media_type`` - Media are ordered alphabetically by MIME-type.
+  - ``quarantined_by`` - Media are ordered alphabetically by the user ID that
+    initiated the quarantine request for this media.
+  - ``safe_from_quarantine`` - Media are ordered by the status if this media is safe
+    from quarantining.
+
+- ``dir`` - Direction of media order. Either ``f`` for forwards or ``b`` for backwards.
+  Setting this value to ``b`` will reverse the above sort order. Defaults to ``f``.
+
+If neither ``order_by`` nor ``dir`` is set, the default order is newest media on top
+(corresponds to ``order_by`` = ``created_ts`` and ``dir`` = ``b``).
+
+Caution. The database only has indexes on the columns ``media_id``,
+``user_id`` and ``created_ts``. This means that if a different sort order is used
+(``upload_name``, ``last_access_ts``, ``media_length``, ``media_type``,
+``quarantined_by`` or ``safe_from_quarantine``), this can cause a large load on the
+database, especially for large environments.
 
 **Response**