----- Original Message -----
Sent: Wednesday, July 07, 2004 2:31
PM
Subject: [ws-caf] RE: clarification of
issue 133
Mark,
It's not really an addressing matter - though
obviously the content of the reference form is affected by the NO addressing
discussion.
We
seem to agree that (rather obviously) the fields of a context-by-value are,
in general, different from the fields of a context-by-reference (a superset
would be a difference). The question then is whether this should be
expressed only in text or in the schema.
But first there is a specific
question of whether the two forms should be explicitly distinguished. Since
a full context (i.e. by-value or as retrieved) might not have any extension
fields or the optional fields, it is not possible to tell just by looking at
a full context that it is in fact full, and de-referencing won't do any
good.
There would seem to be three
ways of distinguishing:
a) there are fields that are
always present in one form but never in the
other
b) there is an attribute that
declares which it is
c) the structure (xml type) is
different.
The first would work if
the context-manager / context-uri choice is never present in a full
context. (but if it were, it really ought to be a different
type). But it would then make it difficult for a full-context to be
dereferenced again (perhaps to pick up updates that have been applied to the
master value at the context manager).
Thus, it seems the effective fields of a full
context have to be a superset of those in a by-reference. So a) is
out.
That doesn't split b) and c), though c) gives the
advantage of forcing a by-reference context to contain only the correct
fields, or fail validation, while b) allows mixtures to be syntactically
valid.
Either way, there
is an impact on the schema.
I would suggest that the fields needed in
by-reference are the identifier (so the receiver knows if he already has
this one), the type (so the receiver knows what it is about) and the EPR/uri
(so the receiver knows where to inflate
it).
Peter
-----Original
Message-----
From: Mark Little [mailto:mark.little@arjuna.com]
Sent: 07 July 2004 11:29
To: Furniss, Peter;
ws-caf
Subject: clarification of issue
133
If it is, then I think this issue should be
closed because we already discussed this at the New Orleans face-to-face
in and around the general subject of addressing. The result was that the
URI that was there has been changed to be an EPR, but the structure was to
remain the same for both formats.
Following on from the above assumption, we
could look at the current text and make sure it's clear that only the EPR
should be sent if by reference.
Mark.
----
Mark Little,
Chief Architect,
Transactions,
Arjuna Technologies Ltd.
www.arjuna.com