Apps Messaging - Semantics of a Message

[Phillip Warner]

On Tue, 10 Apr 2007 13:22:17 -0600 (MDT)
Doug Tody <dtody at nrao.edu> wrote:

> On Tue, 10 Apr 2007, Phillip Warner wrote:
> 
> > Doug said:
> >> I just want to amplify this point.  It appears that everyone agrees
> >> that it is a good thing to separate the messaging mechanism from
> >> the message content; the messaging infrastructure shouldn't know or
> >> care what is in the message, it just delivers it.  We can go one
> >> step further and specify that the infrastructure just delivers the
> >> message payload as an opaque blob of some sort, and it is up to
> >> another layer of software to compose or interpret the message.
> 
> > To take this a step further, if you use, e.g., Java interfaces, you
> > can specify what the underlying messaging infrastructure should be
> > capable of, and leave it up to the programmer to implement the
> > details.  This way you can specify that the underlying protocol
> > should have the ability to, e.g., use transactions, guarantee
> > delivery, yada, etc.  In essence, the interface is the
> > contract-wrapper around the underlying protocol.
> 
> This is the idea (except the part about Java). 

It was only an example.

> That is, we formally specify interface separately from
> implementation.  There was a lot of discussion of this in the earlier
> round of discussions several weeks ago.

Ah... sorry I missed it.  I'll take a look.

Phil