[Erw-devel] New beta, new directions

[erw-devel]

I am leaving for vacation, so I won't be probably work at ERW for a
while.

I have uploaded a new beta at http://erw.dsi.unimi.it/ERW-0.9.8b2.tar.gz
that contains a few bug fixes and new virtual attributes for retrieving
the size of a file (incidentally, I discovered that MIMEtype somehow
vanished from the docs).

There is also a better authorisation system, in which row-based
privileges may be set in a more fine grained way per table, per user and
per group. There are still no docs on this part--I'm sorry, but the
meaning should be obvious. You will have to fix your tables--see
CHANGES.

For the people interested, I would like to lay down the route for 1.0:

1) Fixing the few remaining holes in transactions, in particular the
fact that presently the existence of related elements for r1/r1s is not
always checked.

2) Lifting all restrictions on the usage of absorbed relationship types
in embedded forms and filters. After that, we may gradually phase out
dynamic enumerative types, substituting them with some form of shortcut
for the declaration of a partial function.

3) Clarifying the authorisations induced on adjacent relationship types,
and enforce them. Presently the policy is a bit vague, and
correspondingly the implementation is not very sound.

4) Completing the form customisation system to include filters and
embedded forms.

5) Implementing type transformations. In the library example, if a
person becomes a subscriber there should be a way to just add the
missing data. This is a fundamental step to use type hierarchies to
model state (e.g., having two subtypes of a type that have no additional
attributes, but having different adjacent relationship types).


I would like to get this done by September, as I got a short paper
accepted at ASE 2003 about ERW, and I would like it to be completed by
the time I'll go there (October).

Further development (beyond 1.0) may include:

- More conceptual modelling constructs: part-of, relationship types of
arbitrary arity, higher order relationship types (e.g., between an
entity type and a relationship type), etc.

- Integration with web site production software (Cocoon?) to generate
semiautomatically also a web site.

- Some kind of unit testing. It is not easy for a web system, but I'm
thinking, for instance, of something along the lines of a script-driven
mozilla window that iteratively loads every element of the database.

Any other suggestion, of course, is welcome!

Ciao,

                                seba