[Zope] Example activity-explicit workflow system

Albert Boulanger aboulanger@ldeo.columbia.edu
Wed, 27 Dec 2000 15:31:05 -0500


For those interested in workflow systems and workflow within Zope, the
following workflow system may be useful to try out. It models workflow
steps explicitly and a workflow becomes a graph with a visual editor. I
have been meaning to send along some resources in this area I have been
accumulating.
The Endeavors group at UCI developed this and the peer-to-peer system
they built, Magi, is now at www.endtech.com as open source. They are
still developing the workflow product but an early prototype you can
download and play with is at:

http://www.ics.uci.edu/pub/endeavors/endeavors.html

See also the papers and the web-based workflow thesis at:

http://www.ics.uci.edu/pub/endeavors/docs/papers/

There was discussion of graphical system to present workflow. I have
looked at several, including the At&T stuff. When I have time, I will
send a separate email with some that I have found. One thing to look at
which is ActiveX based at the moment is http://www.lassalle.com/ A
general purpose Flowcharting/Diagramming ActiveX control.

I am very interested in a general, fairly full featured  workflow system
on top of Zope as opposed to using an external workflow product for a
fundamental reason. While one could come up with a way of getting what I
need with an external system, it would be messy. I need workflows to be
explicit and versioned. We make use of ZODB to version content that end
users generate. We don't make use of Zope's versioning but use or own
hierarchical version tree which is easy to do in Zope. End users
generate new workflows and revisit  past workflows. The user sees this
versioning as notebook pages using a scientific notebook metaphor.

It is much cleaner to use ZODB and ZPublisher to do all this instead of
having a version tree in Zope and a bunch of correspondences to outside
objects in an external workflow system. Thus,  there is a lot of value
in having a fairly general workflow system whose representation and
publishing uses ZODB and ZPublisher.

There seems to be a principle here on how to layer systems correctly on
top of ZODB and ZPublisher or any persistant-object web publishing
system. One way is very clean and simple and other ways are nightmares.

Regards,
Albert Boulanger
aboulanger@vpatch.com