[Zope3-dev] what is ZCML?

[Jim Fulton]

Shane Hathaway wrote:
...

> Back on topic, the message I'm hearing about ZCML is confusing:

That's because we don't all agree.

 > high
> level configuration is good, but ZCML isn't going to handle it because 
> we want to limit the number of directives.  Does that mean we're going 
> to use Python code to generate ZCML?  (That's a rhetorical question... I 
> think.)

What I've said is that ZCML should be about configuration, especially
registration, and *not* about defining things.  I've said things should be
defined in Python and registered in ZCML.  I don't necessarily have a problem
with high-level configuration directives that configure several things at
once, although I'm wary that the benefit would be worth the obscurity.

I'd also like to acknowledge Tres' point about high-level non-Python
definition mechanisms for things like forms and schemas.  I agree
with him that such facilities could be a good thing.  I may disagree
with him on whether these should be ZCML. I definately don't think
that they should be.

Finally, I'll note that I've used the term "high-level configuration" to
refer to the things we have sysadmins edit when they install Zope
systems.  We currently use ZConfig for this.  I don't think ZCML
(or any other XML-based system) should be used for this.

Jim

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