Re: [wsrm] Duplicate of Delivered Fault revisited

[Sunil Kunisetty <Sunil.Kunisetty@oracle.com>]

 Tom,

 Could you explain what idempotent means in R-R operation case which is
 essentially a combination of 2 one-way messages?

 It is clear what it means for a (one-way) message, but I always have  difficulty
 in understanding it in terms on R-R case.

 -Sunil

Tom Rutt wrote:

> Sunil Kunisetty wrote:
>
> > Tom,
> >
> > Good observation. For similar reasons, I didn't want to have batching of Acks
> > on R-R. Infact, for all these reasons, I never wanted (or rather was never
> > enthusiastic about)  RM support for WSDL 1.1 R-R operations.
> >
> > So we have couple of choices here:
> > 0)  Remove RM support completely for WSDL 1.1 R-R operations
> >
> >
> Unacceptable
>
> > 1)  Or , say DE doesn't make sense for R-R operations
> >
> >
> unacceptable, this is  a main reason to use it, to protect non
> idempotent ops
>
> > 2)  Or,  create a new thing called 'warning' (like ack and fault) and
> >       for R-R DE case, deliver the msg. to the destination and send the
> >       response along with the 'warning'.
> >
> >
> will not protect agains non idempotent operations.  Not acceptable
>
> > 3)  Or, just send a Http response back (i.e., response doesn't have any SOAP
> >      envelope or just SOAP envelope with no body/header/attachment entries.
> >
> >
> This will confuse the soap/wsdl processor, which is expecting a soap body.
>
> > 4)  Or, create a new fault for DE for R-R case and send the fault...
> >
> >
> I believe this is the best soluction.  It is a fault condition, since
> the rmp has nothing to put in the soap body to obey the wsdl contract.
>
> > The problem with 4 is that, if the Ack & Response was lost on the first invocation,
> > he cannot ever get the response unless he changes the Message Id.
> >
> >
> That is ok, since we are not offering relibility on the response.
>
> > I prefer (0), but I know it will be too drastic and critical at this stage. If not (0), I
> > prefer (4).
> >
> > -Sunil
> >
> >Tom Rutt wrote:
> >
> >
> >
> >>I have come up with a scenario, that makes me want to reconsider sending
> >>an ack for a dupcate of delived message.
> >>
> >>Suppose we have a wsdl , non idempotent, request response operation type
> >>which the user wants to protect with ws-reliability.
> >>
> >>Lest look at the response reply patern .
> >>
> >>So if the first time the operation is invoked, the receiver will deliver
> >>it, and the operation response will carry the rm ack.
> >>
> >>Now if the sender gets nervous and resends just before it receives an
> >>ack, it will be detected as duplicate, by the receiving rmp.  Now
> >>the receiving rmp must not deliver this second operation invocation to
> >>the receiving app, so what does it put in the soap body for
> >>this response.  We are calling it a rm ack, so we will not trigger a
> >>fault condition.
> >>
> >>What would happen if the body was empty, with no indication of faulut in
> >>the ws response header.
> >>
> >>Perhaps we should return a "duplicateOf Delivered" fault code to convey
> >>the situation in an unambiguous manner.
> >>
> >>--
> >>----------------------------------------------------
> >>Tom Rutt                email: tom@coastin.com; trutt@fsw.fujitsu.com
> >>Tel: +1 732 801 5744          Fax: +1 732 774 5133
> >>
> >>To unsubscribe from this mailing list (and be removed from the roster of the OASIS TC), go to http://www.oasis-open.org/apps/org/workgroup/wsrm/members/leave_workgroup.php.
> >>
> >>
> >
> >
> >
>
> --
> ----------------------------------------------------
> Tom Rutt                email: tom@coastin.com; trutt@fsw.fujitsu.com
> Tel: +1 732 801 5744          Fax: +1 732 774 5133
>
> To unsubscribe from this mailing list (and be removed from the roster of the OASIS TC), go to http://www.oasis-open.org/apps/org/workgroup/wsrm/members/leave_workgroup.php.