W3C home > Mailing lists > Public > public-ws-chor@w3.org > November 2004

Re: Corrected Coordinated Choreographies Proposal 4 - Finalize Activity

From: Gary Brown <gary@enigmatec.net>
Date: Tue, 2 Nov 2004 16:45:28 -0000
Message-ID: <00c801c4c0fb$600ac7a0$0200a8c0@LATTITUDEGary>
To: "Haugen Robert" <Robert.Haugen@choreology.com>, <public-ws-chor@w3.org>

Hi Bob,

I think the last two paragraphs of this proposal don't fit with the example. 
If you consider that the example is effectively in a default workunit, then 
the fact that you have a choice construct, means that there is more than one 
finalize statement for the same choreography and choreography instance.

I don't think you can place these restrictions on a workunit - possibly you 
would need to say that in cases where two or more finalize statements are 
executed for the same choreography (+instance), then only the first would be 
enacted. You could also possibly say that inadvert specification of multiple 
finalize statements SHOULD be detected during the static analysis of a CDL 
document???

Regards
Gary

----- Original Message ----- 
From: "Haugen Robert" <Robert.Haugen@choreology.com>
To: <public-ws-chor@w3.org>
Sent: Monday, November 01, 2004 7:59 PM
Subject: Corrected Coordinated Choreographies Proposal 4 - Finalize Activity


> Coordinated Choreographies Spec Changes for Finalize
> Plain text inline, pdf or word.doc sent on request.
>
> Choreology Proposal 4: Finalize activity
>
> In section 2.5 Activities, insert after list item beginning "A No
> Action, which provides...":
>
> * A Finalize, which activates a particular finalizer in a
> particular instance of an immediately enclosed inner choreography and
> thus brings that choreography to a defined conclusion.
>
> Add a new section as follows:
>
> 2.5.7   Finalize activity
>
> The Finalize activity is used to activate a particular finalizer in a
> particular instance of an immediately inner choreography which has
> defined finalizers, and thus bring that choreography to a defined
> conclusion.
>
> The syntax for finalize is:
> <finalize  name="ncname"?
>      finalizerName="ncname"?
>      choreography="ncname"
>      choreographyInstance="xsd:string"?>
> <-- extensibility element -->
> </finalize>
>
>
> A Choreography MUST NOT have any finalize elements if it does not
> encompass any immediate inner choreographies that have defined
> finalizers.
>
> A Choreography MUST have at least one finalize element for each
> immediate inner choreography with finalizers that it encompasses.
>
> A Choreography SHOULD have at least one finalize element for each
> finalizer in an immediate inner choreography that it encompasses.
>
> A Choreography MAY have more than one finalize element for a named
> finalizer in an immediate inner choreography that it encompasses, as
> long as those finalize elements are contained in different Work Units
> with different guards.
>
> The attribute name is used for specifying a distinct name for each
> finalize element declared within a Choreography Package.
>
> The attribute finalizerName indicates which finalizer is to be used to
> finalize a choreography. If the target inner choreography has only one
> finalizer, finalizerName is optional. If the inner choreography has more
> than one finalizer, finalizerName is required.  Its value MUST
> correspond exactly with the name attribute value of a finalizer in the
> target choreography instance.
>
> The required attribute choreography indicates the target choreography
> instance that this finalize refers to when taken with the value for
> choreographyInstance.
>
> The optional attribute choreographyInstance indicates the target
> choreography instance that this finalize refers to when taken with the
> value for choreography attribute.  The choreographyInstance attribute
> MAY be omitted when only one instance of a choreography can be active
> when the work unit guard governing this finalize is evaluated, otherwise
> it MUST be present.
>
> The conditions under which a finalize is chosen is governed by the guard
> on the work unit construct that encloses it.  A work unit MUST contain
> only one finalize for a particular choreography instance.  IT MAY
> contain more than one finalize, so long as each relates to a different
> choreography instance.
>
> This means that finalize elements for the same choreography instance
> MUST be in different work units, and these work units MUST have mutually
> exclusive guards.
>
> (Note: these conditions ensure that one and only one of the finalizers
> in a choreography are chosen to finalize any choreography that has at
> least one finalizer.)
>
> Example:
>
> [Note: this example does not show CDL for the creation of the
> choreographyInstance values. That CDL awaits the unfinished Proposal 5,
> Choreography Instances.]
>
> <choreography name="CreditDecider" root="true">
>
>    <!-- only a snippet shown -->
>    <sequence>
>
>        <!--  other stuff here -->
>        <parallel>
>            <perform name="creditForA"
> choreographyName="CoordinatedCreditAuthorization">
>                <!-- bind such that this does the business for A -->
>            </perform>
>            <perform name="creditForB"
> choreographyName="CoordinatedCreditAuthorization">
>                <!-- bind such that this does the business for A -->
>            </perform>
>        </parallel>
>
>        <!--  other stuff here -->
>
>        <choice>
>            <!--  events have occurred such that A is chosen -->
>            <parallel>
>                <finalize name="creditForA" finalizerName="drawDown"
> choreography="CoordinatedCreditAuthorization"
> choreographyInstance="creditForA"/>
>                <finalize name="creditForB" finalizerName="replenish"
> choreography="CoordinatedCreditAuthorization"
> choreographyInstance="creditForB"/>
>            </parallel>
>
>
>            <!--  events have occurred such that B  is chosen  -->
>            <parallel>
>                <finalize name="creditForA" finalizerName="replenish"
> choreography="CoordinatedCreditAuthorization"
> choreographyInstance="creditForA"/>
>                <finalize name="creditForB" finalizerName="drawDown"
> choreography="CoordinatedCreditAuthorization"
> choreographyInstance="creditForB"/>
>            </parallel>
>
>            <!--  events have occurred such that neither is chosen -->
>            <parallel>
>                <finalize name="creditForA" finalizerName="replenish"
> choreography="CoordinatedCreditAuthorization"
> choreographyInstance="creditForA"/>
>                <finalize name="creditForB" finalizerName="replenish"
> choreography="CoordinatedCreditAuthorization"
> choreographyInstance="creditForB"/>
>            </parallel>
>        </choice>
>
>    </sequence>
>
> </choreography>
>
>
> Choreology Anti virus scan completed
> 
Received on Tuesday, 2 November 2004 16:45:52 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Saturday, 18 December 2010 01:01:10 GMT