Fixed #27030 -- Added contrib.postgres.indexes.GinIndex.

docs/ref/contrib/postgres/index.txt

@@ -35,6 +35,7 @@ release. Some fields require higher versions.
     fields
     forms
     functions
+    indexes
     lookups
     operations
     search

docs/ref/contrib/postgres/indexes.txt

@@ -0,0 +1,24 @@
+=================================
+PostgreSQL specific model indexes
+=================================
+
+.. module:: django.contrib.postgres.indexes
+
+.. versionadded:: 1.11
+
+The following are PostgreSQL specific :doc:`indexes </ref/models/indexes>`
+available from the ``django.contrib.postgres.indexes`` module.
+
+``GinIndex``
+============
+
+.. class:: GinIndex()
+
+    Creates a `gin index
+    <https://www.postgresql.org/docs/current/static/gin.html>`_.
+
+    To use this index, you need to activate the `btree_gin extension
+    <https://www.postgresql.org/docs/current/static/btree-gin.html>`_ on
+    PostgreSQL. You can install it using the
+    :class:`~django.contrib.postgres.operations.BtreeGinExtension` migration
+    operation.

docs/ref/models/indexes.txt

@@ -56,3 +56,8 @@ case, a descending index is created as a normal index.
 The name of the index. If ``name`` isn't provided Django will auto-generate a
 name. For compatibility with different databases, index names cannot be longer
 than 30 characters and shouldn't start with a number (0-9) or underscore (_).
+
+.. seealso::
+
+    For a list of PostgreSQL-specific indexes, see
+    :mod:`django.contrib.postgres.indexes`.