Re: [Zope3-Users] Utility Local to an Annotation?
Derek Richardson-2 wrote: Benji York wrote: Derek Richardson wrote: The specific case is uuids for atom feed entries. We have annotations representing feeds and I would like my uuid utility to be local to the feed annotation, thus recording and making available uuids only for entries in that feed. How about a multi-adapter from content and feed to UUID? Hmmm, to do that I have to be able to annotate an annotation, right? As the feed is an annotation and that is where I want to store the UUIDs. I tried this tonight and was unable to make it work - I got the following: There's no reason why you can't mark an object that you fish out of an annotation with IAttributeAnnotatable and then annotate that. However, this feels suspiciously like you're asking the wrong kind question. :) Can you explain (a) what you are trying to store (what is a feed in this case? is it just feed-specific metadata? or an actual list of items rendered to RDF?) and (b) what you need UUIDs for and (c) when you need to use the UUIDS? Martin -- View this message in context: http://www.nabble.com/Utility-Local-to-an-Annotation--tf3646832.html#a10217406 Sent from the Zope3 - users mailing list archive at Nabble.com. ___ Zope3-users mailing list Zope3-users@zope.org http://mail.zope.org/mailman/listinfo/zope3-users
Re: [Zope3-Users] Utility Local to an Annotation?
Derek Richardson-2 wrote: Yes, it does feel like I'm going about this the wrong way. a - The feed is actually just configuration metadata - whether the feed is enabled, whether it is recursive, what its display name is, etc. The actual feed document is not stored - it is simply rendered dynamically when requested, based on the metadata and the existent content items. The feed is an annotation on a container; at the current time, only folders are feeds and only contained files are feed items. Okay, so the feed is really a view, which consults some annotations on a container and then recursively looks for objects in that container and constructs XML? b - In the Atom syndication format, UUIDs are necessary for two things. One, the overall feed has a UUID. This is easy - I'm storing them in a site-local named utility, indexed by the feed annotation object. What do yuo mean indexed by? Also, is this UUID not just another aspect of feed metadata and thus a candidate for the container annotation? Two, each entry in a feed has a UUID. A content item that is an entry (a file, in the current case) can, however, be in multiple feeds and needs a different UUID in each. Thus, I need to be able to look up UUIDs by the content object that will be rendered as a feed entry and look them up relative to the feed, rather than globally. That sounds to me like you want a composite UUID - a UUID utility gives each content item a UUID (which is not feed-specific, and stays in line with the general concept of a content object UUID). The one you put in the feed is the feed's UUID and the object's UUID are combined. You could possibly use some kind of hash if you needed to. c - I use the UUIDs only when rendering the feed, looking them up by object and sending them to the client embedded in the feed document. They are used for no other purpose. Still, the concept of a UUID of a content object ought to be separate from and more general than your particular need for a feed item UUID. So, my situation is that I've written my nifty uuid utility based on intid and I want to reuse it for feed entry UUID lookup. I can't use unnamed utilities because I may be accessing different uuid utilities for entries from the same place in the tree. It occurs to me that I could make them named utilities local to the object underlying the entry and look them up by the feed UUID they correspond to, but, in my understanding, that would require littering sites all over the place, which seems like bad citizenship. It does. I would not do this at all. I think the cleanest design would be: - You have a generic object UUID facility - You make a UUID for a feed when you create it, and store it in the feed annotation - You generate feed item UUIDs on the fly from a hash/concatenation of the feed UUID and the generic object UUID Martin -- View this message in context: http://www.nabble.com/Utility-Local-to-an-Annotation--tf3646832.html#a10221944 Sent from the Zope3 - users mailing list archive at Nabble.com. ___ Zope3-users mailing list Zope3-users@zope.org http://mail.zope.org/mailman/listinfo/zope3-users
Re: [Zope3-Users] Utility Local to an Annotation?
On 4/27/07, Martin Aspeli [EMAIL PROTECTED] wrote: I think the cleanest design would be: - You have a generic object UUID facility - You make a UUID for a feed when you create it, and store it in the feed annotation - You generate feed item UUIDs on the fly from a hash/concatenation of the feed UUID and the generic object UUID if you are generating UUID's based on the feed-specific UUID and a unique identifier for the object, you could just use the already present intid.. -- Martijn Pieters ___ Zope3-users mailing list Zope3-users@zope.org http://mail.zope.org/mailman/listinfo/zope3-users
[Zope3-Users] Utility Local to an Annotation?
I would like to create utility instances that are local to annotation instances. Each utility would be valid only within the scope of the related annotation. The specific case is uuids for atom feed entries. We have annotations representing feeds and I would like my uuid utility to be local to the feed annotation, thus recording and making available uuids only for entries in that feed. See http://www.openplans.org/projects/vice/uuids-in-atom for more details and an architectural diagram. FYI, an object can be syndicated in more than one feed. Thus, for feed X, I want to look up the uuid associated with object a for feed x; for feed y, I would want the *different* uuid associated with object x (same object) for feed y. However, I am not sure I can turn an annotation into a site and, even if I can, am not sure that's what I want to do. Comments? Suggestions? Thanks, Derek ___ Zope3-users mailing list Zope3-users@zope.org http://mail.zope.org/mailman/listinfo/zope3-users
Re: [Zope3-Users] Utility Local to an Annotation?
Derek Richardson wrote: The specific case is uuids for atom feed entries. We have annotations representing feeds and I would like my uuid utility to be local to the feed annotation, thus recording and making available uuids only for entries in that feed. How about a multi-adapter from content and feed to UUID? -- Benji York Senior Software Engineer Zope Corporation ___ Zope3-users mailing list Zope3-users@zope.org http://mail.zope.org/mailman/listinfo/zope3-users
