[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [seul-edu] Consolidated gradebook effort




On Wed, 9 Feb 2000, Hilaire Fernandes wrote:

> It will be a good idea to separate the GUI of the gradebook from the
> core of the gradebook. We will define an abstract GUI from which
> specific GUI will be derived. This will make port more easy and will
> allow to have both a GTK & HTML interface. So the gradebook could be
> used as a standalone application and also as a kind of CGI in a
> school web server.

I agree with this completely.  In fact, I think we ought to be extremely
careful in designing the architecture for this.  We've all pretty much
agreed that EduML is the right data format for storing data, whether it be
a gradebook, a quiz, or a web-based collaborative environment.  However,
how can we make all these applications work together?  In order for EduML
to achieve it's potential, we not only need to define a specificiation for
storing the information, but we also need to specify how the data is to be
interchanged.

For example, if a school has a network of machines, a teacher should be
able to open a gradebook application on any machine, and work with his/her
grade data.  Suppose the registrar deletes a student from the school's
roster.  This change should be reflected immediately in the school's
web-based environment and in the gradebook application.  Thus, the
gradebook needs to do more than just open an XML file and parse it into
internal data structures using libxml.  Multiple applications need to be
able to work with the same database simultaneously, and changes needed to
applied consistently.

I've looked around on the web, searching for work already done in this
area, and it seems like there is progress.  XQL (XML Query Language) and
XML-QL are query languages designed to query information from an XML
document (database).  However, I have not seen any indication of the
ability to do insert/delete/replace operations on an XML document.  This
would be necessary if we were to access an XML document as a database in
a platform and language portable way.

Also, how do we use the same data for all these different applications
across a network?  There seems to be some work towards using CORBA as a
method of transmitting XML data across a network.  But is there any
progress on using such a method to transmit XQL or XML-QL queries?  Also,
how to we keep this system flexible?  In one case, we may have a teacher
that wants to run their gradebook on his/her home computer.  In that case,
we need XML processing capability directly in the application so that
installation is not too difficult.  But how do we allow the same
application to plug-in transparently to a network that uses CORBA and a
central XML (or EduML) data repository?  And how can we allow the teacher
to seemlessly import his XML data created at home into the central XML
data repository at school?

Once we are trying to support all these capabilities in the application,
have we lost sight of the original reason for choosing EduML?  EduML is
good because it allows for a common data storage format in education.  But
how do we allow multiple applications to share this data across the
network without hindering an application's ability to stand on its own in
the absense of such an environment?

In other words, if we want a gradebook application to truly realize the
potential of EduML, we need to do more than just parse an XML file with
libxml.  Such functionality would not allow us to share data with other
applications.  Or am I missing something?

I would appreciate any insight into this problem that anyone has.

Regards,

David Moore


------------------------------------------------------
  David Moore       California Institute of Technology
 <dcm@acm.org>             http://www.mbhs.edu/~dmoore
------------------------------------------------------