Santi Camps wrote:
Casey Duncan wrote:
Zope2 folders are designed for this. They are really just "blank objects" where you can specify your own methods in instance space. Traditionally in Zope2, there are two ways to do this: by adding "method" objects (External Methods, DTML methods, python scripts, ZPT) directly to the folder. Or by adding these objects "above" the folders and aquiring them which is a type of environmental inheritance. In the CMF this is codified in the skins tool which contains global methods which can be applied to basically any object in the site.
Great explanation - would you give me a hint on the CMF part ? Which global methods do you speak of ?
The CMF has a "Tool" infrastructure. Tools are persistent objects typically at the top of the CMF site. Tools provide methods and configuration for use by all objects in the site via acquisition. For example, the membership tool (portal_membership), provides methods to access member information and member folders.
The portal_skins tool is special in that it actually contains framework and application defined method objects (scripts, templates, etc) organized into layers and configured into skins (which are lists of layers to use). The CMF Site object is a special "Skinnable" folder which allows methods available in the current skin (as described in the skins tool) to be acquired through it. This makes all of the method objects in the skin's layers globally available to all objects in the CMF site.
This solves several problems, one of which is a tendancy of top-heavy hierarchies in zope where lots of objects are in the root because they need to be global. The skin and layer mechanisms allow different sets of methods to be available depending on the application, products installed, site policy and user preferences.
-Casey
Very interesting. That's what I was looking for. I will try to extract this mechanism from CMF.
Chris McDonough has already released a "standalone" version of the skins tool: http://plope.com/Members/chrism/standalone_skins Tres -- =============================================================== Tres Seaver tseaver@zope.com Zope Corporation "Zope Dealers" http://www.zope.com