I am refering to the pdf document "User interface update for SDL Tridion 2011 SP1 Installation Manual_tcm89-20507.pdf" for installing Tridion UI 2012. While following the instructions I am stuck at a point where we need to configure storage for session preview on the Content Delivery session preview Web service and also on staging Web site.
Do we need to do this both on the session preview Web service and staging Web site, or is it sufficient only to do it on the session preview Web service?
Both sites will need the Wrapper element in their cd_storage_conf.xml I believe.
Albert wrote a great guide to help here: http://albertromkes.com/2013/01/24/troubleshooting-the-sdl-tridion-experience-manager-with-session-preview/
The reason for it is something along the lines of both applications need to know the location of the session preview database, so one can store content in it, and the other can read from it. Similar to how both your website and Deployer need to have the same Broker database in their storage conf.
As mentioned, yes, you do need the wrapper on both stacks, and here's the why.
If you look at the data flow (see the diagram at the bottom of this post), after you commit changes, the Content Manager will package and send the updates to the Content Delivery Web Service. The WebService will understand that this is temporary data, and store it in the database defined in the wrapper.
The Staging site will then pick up these changes from the database defined in the wrapper (and this is why it must be the same DB).
A common source of confusion in this topic is that some people think the webservice is used to retrieve the temporary data, but that's not the case, the webservice is only used to store the temporary data in the database, and standard JDBC is used to retrieve it.
