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

[Mike Edwards <mike_edwards@uk.ibm.com>]

Jacques,

Regarding Comment 12:

You may like to take a look at the OSOA
SCA Event Processing specification which has been submitted to the OASIS
Assembly TC
and which forms part of the input to
the resolution of Assembly Issue-80:

http://www.oasis-open.org/apps/org/workgroup/sca-assembly/download.php/32379/SCA_Assembly_Extensions_for_Event_Processing_and_PubSub_V1_0.pdf

While not in any way official as far
as OASIS is concerned, it does show an SCA model for a more decoupled model
for interaction between components using
event sending and pub/sub techniques.


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:  mike_edwards@uk.ibm.com

From:	"Jacques R. Durand" <JDurand@us.fujitsu.com>
To:	<sca-assembly-comment@lists.oasis-open.org>
Date:	23/06/2009 22:48
Subject:	[sca-assembly-comment] Some more comments

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[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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