RV: [Long] Development in Zope (Was: Re: [Zope] data point on ease of learning Zope -- I give up.)

Ernesto Revilla aerd@retemail.es
Sun, 18 Mar 2001 20:42:02 +0100


Hi Cees,

> You may want to check out Smalltalk. Especially for an ERP solution I
> would not use Zope - ERP is lots of business logic, and I have tried
> three different ways of doing lots of business logic with Zope, and
> no one is satisfying.
What about the GUI? Does it user standard browser technology or some client
software? Is there any tool that assist the creation of GUI screens/pages?
What's about Web publishing / applications server? What's about the object
store?

> For lots of business logic, if you want to stick with Python, I would
> recommend WebWare which has a more "classical" setup, with Python Server
Pages
> and Servlets serving your users (PSP being the "View" and Servlets often
> acting as the "Controller"), and raw Python code containing the logic (the
> "Model" part of the picture). It has lots of bells and whistles in the
latest
> version, among others an object-relational mapping layer (no OQL though).

I should have a look soon.

> If you're not married to Python, I'd seriously consider Smalltalk. It's
even
> more effective than Python, but one caveat is that certainly in the
beginning
> you probably want an experienced Smalltalk "coach" on your team. Coupling
> Smalltalk to eXtreme Programming practices will probably result in an ERP
that
> easily outperforms SAP R/3 on most fronts ;-)

Still I'm not married to Python. But I like the language. I really don't
know much about SAP R/3, but I found that it is very expensive to have a
good SAP installation / configuration. The guys which customize it earn
well. Also I found that we can compete easily with SAP in smaller business,
e.g. 5-30 workstations. (We have some companies here which are not very
satisfied with SAP, but this seems to be responsability of the company which
is installing, configuring and customizing it.) Good abstractions make the
code modular and the application feasable. Also we have about 130 tables,
using good class abstraction could reduce them to the half. We have about 90
code-modules and more than tha half are libs (reusable for other projects),
a lot very generic functions. I did all the programming and the most of the
GUI designing myself. It took about 2 years, everything included. Out app is
running at 12 customers. And it is the same application for everyone. Only
print reports (invoice form, orders, etc.) are customized. There are really
a lot features demanded by all customers, such that the possibility to
attach whatever other document to standard documents handled in the app
(invoice, delivery note, project, etc.) and incidence tracking (to study
cost-benefit, you only have to track what activity (=article) have you done
for which customer/project).

I would like to write an Open Source ERP whith all the standard thinks
(Selling (Orders, deliveries / invoices) / Buying (same)/ Accountig / Stock
/ Incident tracking and some workflow/approvement cycles). Also I think that
business models in Europe are very similar.

I would like to know something about TransWarp from Phillip Eby. Will this
help developing apps faster?


> (ok, I'm exagerating...)
Perhaps not.... ;-)

> Cees de Groot               http://www.cdegroot.com     <cg@cdegroot.com>
Erny