Documenting the media_manager fetching hook

This commit sponsored by Christian Corrodi.  Thank you!

diff --git a/docs/source/pluginwriter/media_type_hooks.rst b/docs/source/pluginwriter/media_type_hooks.rst
index 0dfbbafd4b5bb71af313b802edb580039d915740..498b0b540dd9d02d0d9196293238865a819cc1a4 100644 (file)
--- a/docs/source/pluginwriter/media_type_hooks.rst
+++ b/docs/source/pluginwriter/media_type_hooks.rst
@@ -25,3 +25,14 @@ This hook is used by ``get_media_type_and_manager`` in
 ``mediagoblin.media_types.__init__``. When this hook is called, your media type
 plugin should check if it can handle the given extension. If so, your media
 type plugin should return the media type and media manager.
+
+('media_manager', MEDIA_TYPE)
+-----------------------------
+
+If you already know the string representing the media type of a type
+of media, you can pull down the manager specifically.  Note that this
+hook is not a string but a tuple of two strings, the latter being the
+name of the media type.
+
+This is used by media entries to pull down their media managers, and
+so on.