Add cookbook entry.

Author: Drak

cookbook/index.rst

@@ -25,6 +25,7 @@ The Cookbook
     debugging
     event_dispatcher/index
     request/index
+    session/index
     profiler/index
     web_services/index
     symfony1

cookbook/map.rst.inc

@@ -102,6 +102,10 @@
 
   * :doc:`/cookbook/request/mime_type`
 
+* :doc:`/cookbook/session/index`
+
+  * :doc:`/cookbook/session/php_bridge`
+
 * :doc:`/cookbook/routing/index`
 
   * :doc:`/cookbook/routing/scheme`

cookbook/sessions/index.rst

@@ -0,0 +1,7 @@
+Sessions
+========
+
+.. toctree::
+    :maxdepth: 2
+
+    php_bridge

cookbook/sessions/php_bridge.rst

@@ -0,0 +1,36 @@
+.. index::
+   single: Sessions
+
+Bridge a legacy application with Symfony Sessions
+--------------------------------------------------------
+
+.. versionadded:: 2.3
+Added ability to integrate with a legacy PHP session
+
+You may take advantage of the PHP Bridge Session when integrating
+a legacy application into the Symfony Full Stack Framework when it
+may not be possible to avoid the legacy application starting the
+session with ``session_start()``
+
+If the application has sets it's own PHP save handler, you can
+specify null for the ``handler_id``:
+
+.. code-block:: yml
+
+    framework:
+        session:
+            storage_id: session.storage.php_bridge
+            handler_id: ~
+
+Otherwise, if the problem is simply that you cannot avoid the application
+starting the session with ``session_start()`` but you can still make use of
+a Symfony based session save handler, you can specify the save handle
+as in the example below:
+
+.. code-block:: yml
+
+    framework:
+        session:
+            storage_id: session.storage.php_bridge
+            handler_id: session.handler.native_file
+