Steve Alexander wrote:
Shane Hathaway wrote:
So it's mostly right-to-left, but sometimes left-to-right, and sometimes in a less than predictable order. I have an external method that makes it clearer, if you're interested.
Yes please!
This method, instead of showing the acquisition algebra, shows the actual graph of acquisition wrappers. It's ordered in such a way that you can search it from top to bottom to figure out exactly the behavior of Acquisition.c. Install this as an external method "showaq" at the base of your Zope installation. Then try different acquisition paths: http://localhost:8080/QuickStart/showaq http://localhost:8080/QuickStart/Outline/QuickStart/showaq http://localhost:9080/QuickStart/Outline/QuickStart/Control_Panel/showaq A vertical line refers to aq_parent, which is a "context" link. A diagonal line refers to aq_self, which is a "containment" link. Containment never changes; it refers to the physical location of an object. Context, on the other hand, can be modified easily just by changing the URL. Some objects are in parentheses because they are not actually searched. But you'll notice that objects in parentheses have both an aq_self and an aq_parent which refer to the same object. I suppose this method could be cleaned up to eliminate the redundancy, but my goal was to see the actual structure of the wrappers. So, without further ado, here is the method. def showaq(self, indent=''): rval = "" obj = self base = getattr(obj, 'aq_base', obj) try: id = base.id except: id = str(base) try: id = id() except: pass if hasattr(obj, 'aq_self'): if hasattr(obj.aq_self, 'aq_self'): rval = rval + indent + "(" + id + ")\n" rval = rval + indent + "| \\\n" rval = rval + showaq(obj.aq_self, '| ' + indent) rval = rval + indent + "|\n" if hasattr(obj, 'aq_parent'): rval = rval + indent + id + "\n" rval = rval + indent + "|\n" rval = rval + showaq(obj.aq_parent, indent) else: rval = rval + indent + id + "\n" return rval Shane P.S. I wouldn't mind if someone posted this as a HOWTO. :-)