Making a custom class addable to another class in product, but not to Zope
Greetings. I'm relatively new to Python-based development of Zope products. I've got two classes in my product; let's call them Container and Thing. I want to have Container addable to any old folder in the ZMI; that's no problem, I just register it in my product's __init__.py file. I want Container to allow instances of Thing to be added to it, and nothing else; that's also no problem, using all_meta_types. However, I want Thing to be addable to Container, but not to any other ObjectManager-based object. I can't figure that one out. I assumed I could do it by having an entry for Thing in Container's all_meta_types property, and by *not* registering it in __init__.py. Unfortunately, that fails. If I click on the "Add Thing" button in the ZMI when viewing the content of a Container, I get Cannot locate object at http://localhost:8080/kb0/manage_addProduct/ [ignore line break] MyProduct/manage_addThingForm If I register Thing in __init__.py, then the Add Thing button works perfectly, but I can add a Thing to any folder in the ZMI. It looks like the registration process is necessary to get manage_addThingForm added to whatever registry of constructors manage_addProduct['MyProduct'] accesses. Is there a way around this? I'd think what I'm trying to do is pretty standard, but I can't find anything enlightening. Thanks, ..Ian
Ian Beatty wrote:
manage_addProduct['MyProduct'] accesses. Is there a way around this? I'd think what I'm trying to do is pretty standard, but I can't find anything enlightening.
Have a look at the code in the PlugginIndexes product tha tships with Zope, since it works in exactly the way you describe... cheers, Chris -- Simplistix - Content Management, Zope & Python Consulting - http://www.simplistix.co.uk
Ian Beatty wrote at 2004-2-24 17:33 -0500:
... I've got two classes in my product; let's call them Container and Thing. I want to have Container addable to any old folder in the ZMI; that's no problem, I just register it in my product's __init__.py file. I want Container to allow instances of Thing to be added to it, and nothing else; that's also no problem, using all_meta_types.
However, I want Thing to be addable to Container, but not to any other ObjectManager-based object.
You simply do not register "Thing". You define "constructors" (they are factories indeed, but Zope uses the term "constructors") for "Thing" on "Container", among them the "construtor" for the action you used in "all_meta_types". Your "all_meta_types" will return something like: ( { 'name' : 'Thing', 'action': 'Thing_add', 'permission': ManagePortal, }, ) Note, there is not "manage_addProduct" in the action... -- Dieter
Anoter option is to register a container_filter for the Thing class: def initialize(context): (...) context.registerClass(thingmodule.Thing, permission=thingmodule.ADD_THING_PERMISSION, constructors=(...), container_filter=thingmodule.containerFilter, icon="www/thing.png") where containerFilter is a module global function that could be: def containerFilter(container): isinstance(container, containermodule.Container) This way Zope doesn't show it as addable to anything on the management interface except Containers. I don't think Zope checks the container_filter if the constructors are invoked directly, eg. by a PythonScript, but if you want to be strict, you can invoke the containerFilter again on the constructors and raise an exception... Cheers, Leo. On Wed, 2004-02-25 at 17:52, Dieter Maurer wrote:
Ian Beatty wrote at 2004-2-24 17:33 -0500:
... I've got two classes in my product; let's call them Container and Thing. I want to have Container addable to any old folder in the ZMI; that's no problem, I just register it in my product's __init__.py file. I want Container to allow instances of Thing to be added to it, and nothing else; that's also no problem, using all_meta_types.
However, I want Thing to be addable to Container, but not to any other ObjectManager-based object.
You simply do not register "Thing". You define "constructors" (they are factories indeed, but Zope uses the term "constructors") for "Thing" on "Container", among them the "construtor" for the action you used in "all_meta_types".
Your "all_meta_types" will return something like:
( { 'name' : 'Thing', 'action': 'Thing_add', 'permission': ManagePortal, }, )
Note, there is not "manage_addProduct" in the action... -- Leonardo Rochael Almeida <leo@hiper.com.br>
participants (4)
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Chris Withers -
Dieter Maurer -
Ian Beatty -
Leonardo Rochael Almeida