----- 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