[Zope3-dev] Zope 3 Questions

[Jim Fulton]

Shane Hathaway wrote:
> Jim Fulton wrote:
> 
>> Shane Hathaway wrote:
>>
>>>  That reduces my confusion, since one of the tenets of configuration 
>>> management is that software consists of a combination of components 
>>> from many sources.  You can't just replace the view service with a 
>>> view service from a different package--you really need to be able to 
>>> compose a view service that has components from multiple packages.
>>
>>
>>
>> I don't follow this last bit.
> 
> 
> Say I set up a basic content management site.  Among other services, it 
> sets up a view service.  Now say I want to add features to that site by 
> installing packages into it.  Specifically, I want to install the 
> package that replaces certain text areas with rich text widgets.
> 
> When I install the rich text package, it does not replace the view 
> service, instead it adds to the existing one.  Now I have a view service 
> that's not specific to either content management or rich text editing, 
> so it doesn't logically belong to any package anymore.   It belongs only
> to the "active configuration".  Nearly every package will want to add 
> to, but not replace, the views service.
> 
> Does that map in some way to how Zope 3 packaging works?  I can't quite 
> see it yet.

I think the stubling block is the role of packages. Packages have two roles:

1. Distribution

2. workspace

That is, some package, especially the default package, are there just to provide
a workplace for local configuration. Packages in service managers are a bit like
folders in content space.

Other packages are for distribution. These packages may be packages you
create and put stuff into that you eventually distribute, or they may
be packages that you got from someone else.

Does this help?

Jim

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