Fw: [sca-assembly-comment] Some more comments

Folks,

More comments from the Public Review
list.

I suggest that each of these 3 comments
is treated as a separate Issue for tracking purposes.

Yours,  Mike.

Strategist - Emerging Technologies, SCA & SDO.

Co Chair OASIS SCA Assembly TC.

IBM Hursley Park, Mail Point 146, Winchester, SO21 2JN, Great Britain.

Phone & FAX: +44-1962-818014    Mobile: +44-7802-467431  

Email:  

----- Forwarded by Mike
Edwards/UK/IBM on 24/06/2009 08:55 -----

From:
"Jacques R. Durand" <>

To:
<>

Date:
23/06/2009 22:48

Subject:
[sca-assembly-comment] Some more comments

[Comment 11b] :  The chicken or the
egg... (or the COmposite vs. the Component)

(rewording of my previous comment #11)

 

It is unclear why the Composite is always
the outermost construct, as the markup

indicates. It seems that the mark-up does
not allow to expose the Component

directly to users, yet the component has
the same interfacing constructs

(Services / Properties / References) as the
Composite.

Yet apparently SCA implementations will often
directly expose Components (which may

or may not be implemented as composites),
e.g. in the C++ model.

Couldn't the mark-up reflect this abstraction
and make Component top-level (beside or even instead of Composite?)

NOTE: this comment could be modified along
my previous comment #9: if some form of "container"

is needed for all kinds of SCA constructs
(Services, Rferences, Components, Composites...)

that should probably be something new, different
from "Composite".

 

 

[Comment 12]: Best practices for most typical
architecture patterns?

 

The control model suggested by Composites,
is of Components invoking each others via

references and wires. It is unclear how that
plays with more decoupled architecture patterns 

between components: 

- publish-subscribe async communication between
Components 

(should a queue manager be itself modeled
as a component?)

- event listeners.

 

 

[Comment 13]: I don't think there is a clear
definition of what an "SCA runtime" is.

 

 

Regards,

Jacques

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