[Zope] Questions concerning development in Zope

[J Cameron Cooper]

Iwan van der Kleyn wrote:

Man do these big overview questions take a lot of time!

> * Zope is often criticised for its perceived lack of documentation. 
> Although the current Zope book seems to have improved greatly, I still 
> miss a good reference guide/book on advanded topics (the Development 
> Guide seems to have stuck at version 2.4 and is rather limited). Which 
> book(s) can fullfill this role?

Perhaps. I'm not really sure what fits in the "advanced" category. Most 
of the stuff you see in Java books is plumbing anyway, and you don't 
often have to worry about that with Zope.

> * Zope seems to lack a dominant development methodology/paradigm. 
> DOT.NET has got form-based ASP.NET/ADO.NET, Java has MVC with 
> Struts/J2EE, PHP has either form-based or MVC with Pear/Smarty.

This point is two different questions. This one is "what application 
framework should I use?" The other web-dev platforms you mention are 
very low-level at heart, and these extra layers help avoid the spaghetti 
that's endemic to that model. Zope is a web app framework, based around 
object publishing. Objects are model, they usually provide their own 
views, and object methods and/or glue with Python scripts takes care of 
the controller part (plus the actual function of the app.)

Or you could consider Plone/CMF as a framework (at an evern higher 
level). It's a great way to go even if you only use the skins tool and 
the form controller (another way to get the C part of MVC.) Plus you get 
Archetypes, which is fantastic.

> What shoudl I use in Zope? ZTP with Scripts? Or external Methods? 
> ZCLasses? Products?

This one is "where do I do my Zope development?" Use Products to define 
content and logic, page templates (either from the Product, a skins 
tool, or the ZODB) to render them, and use page templates and Python 
scripts (and maybe a form controller) to glue everything together. 
Forget ZClasses, and look seriously at Archetypes: schema-driven content 
object creation is a real time-saver.

> * Releated to the former question: ASP.NET and PHP (through Pear) 
> excell in easy (fast!) form-based development. What functionality can 
> Zope offer? I've seen some references to a " Formulator"  product.

Not really sure what "form-based development" is. Seems to be a term out 
of the ASP world. If I guess right, Formulator or  Archetypes (esp. with 
"schemata") will do this for you nicely. As to speed, I also do J2EE, 
and it takes for-blasted-ever compared to Zope.

> * Plone seems to be all the rage. But is Plone usable as an 
> application framework? Can I use Plone for form-based, data-driven 
> applications?

That's nice to hear. Plone (or CMF with some Plonish additions) is a 
first-rate framework, even outside the realm of content-based 
applications (although if you go too far out you tend to lose some 
applicability.)

> * Thanks to Python's Global Interpreter Lock, Python programs don't 
> scale well on SMP systems. Which is a "must have"  in our situation. 
> I' ve found some references to using ZEO to circumvent this, 
> effectively running multiple instances of Zope on one server. Is there 
> any documentation to be found on this subject? And how proven is this 
> solution?

Run a ZEO client for each processor. Probably you have to set a 
processor affinity. That's all you need to know (besides how to set up 
ZEO, which is documented in the ZEO docs and a HOWTO or two, and made 
REALLY easy by Zope 2.7.) As for proven-ness, lots and lots of people do 
this, both for multi-processor and multi-machine, and both.

> * And finally (which makes me come across somowhat like a Troll, sorry 
> about that :-). What is the "life expectancy" of Zope? Most of the 
> hype regarding Zope seems to have died away somewhat. Recently its 
> coming back in the slipstream of Plone. But realistically, what are 
> the chances of Zope being a *relevant* application platform in a 
> couple of years time? WIth "relevant"  I mean: a platform which is 
> well supported and keeps up with the compettition on *features*, not 
> necessarilly market share.

Wish my time machine were still working. But I think you can expect Zope 
and its orbit to make a fine showing in the future. I base that partly 
on the fact that it's hard to keep up with all the exciting things going on.

            --jcc