[Zope3-dev] best practices for registry-like functionality

[Jim Fulton]

Garrett Smith wrote:
> I need to manage a set of vocabulary-like objects for a site. These 
> vocab objects will be used by widgets.
> 
> These objects are not content, so I want to store and manage them in a 
> site management folder. Specifically, I need to be able to:
> 
> - Add new vocab objects
> - Edit existing vocab objects
> - Delete vocab objects
> - Lookup a vocabulary by name
> - Get a list of all registered vocab objects
> 
> In the past, I would have written a service for this, which would 
> maintain its own contained set of vocab objects. But I suspect I really 
> want a utility,

In particular, you want to treat each vocabulary as a utility.


 > since the recent trend has been to use utilities over
> services.

Specifically, to use the utility service rather than a custom service.

> The utility would be used to lookup vocab objects and provide a list of 
> registered vocab objects.

Nope, see above

> I also suspect that the utility should not contain the vocab objects, 
> but that the vocab objects should instead be added directly to the site 
> management folder, or perhaps to a Vocabulary-Like Objects Folder ala 
> the Page Folder.
> 
> I'm terribly fuzzy about the recommended approach for this sort of 
> thing. Any help would be much appreciated.

Vocabulary objects are just utilities.  You create them in site-management
folders and register them.

Utilities and services together are "tools".  There is a management
UI for managing tools. You can define new tool types, which are really
just kinds of utilities, like "caches", "catalogs", "database connections",
"vocabularies" and so on.

I know that there already was a vocabulary service that was converted to
use the utility service. I imagibe there are artifacts for this laying around.

All of what I described is straightforward but not well documented at this
point. Sigh.  It will be documented, but we haven't gotten to it yet.

Jim

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