Re: [soa-rm-ra] Re: service interaction [was: [soa-rm-ra] Follow-up to 7-5-08 Telecom]

["Jeffrey A. Estefan" <jeffrey.a.estefan@jpl.nasa.gov>]

Folks,

 

Remember, there are only two types of action:

 

1. [Separate] "Action," which is the application of intent by [A] participant (or agent) in order to achieve a RWE.

2. "Joint Action," which is an action involving the efforts of [TWO OR MORE] participants to achieve a RWE.

 

Note:  The emphasis in brackets is mine.

 

In the context of interaction, we emphasize "joint action" because you have to have a speaker AND a listener in order to interact.  Further, recall that we define the means by which joint actions [and event notifications] are coordinated by service participants (or agents) to be "message exchange," and we define "operations" as the sequence of actions a service must perform in order to validly participate in a joint action.  Consequently, there are indeed separate actions that service performs (i.e., perform operations) and there are joint actions [and event notifications] used for message exchange.  This is why we make the point that messages denote either action (more accurately, joint action) that causes a RWE and events that report a RWE.

 

What we should probably do is make the emphasis on joint action relative to Fig. 40 (based on PRD 1 of the RA) so as to not cause this kind of confusion.  The emphasis on joint action isn't really addressed in until later in Section 4.3.2 when we talk about message exchange.  In addition, it is not just the joint action realized through messages that causes a RWE to occur but also the separate actions (i.e., operations) that the service performs that contribute to the RWE, i.e., it is both types of action performed in concert that leads to a RWE.  This point is not clearly articulated in the RA and needs to be.

 

If yawl agree, I'll make the necessary minor updates to the Interacting with Services model to help resolve this ambiguity before the next PRD.

 

Cheers...

 

 - Jeff