Re: [osgi-dev] Conditional Target

Wed, 26 Jun 2019 07:31:53 -0700

The RFC includes adding support to DS (and CDI) but is service based and can be used in any service model. The RFC also includes configuration based support for creation of Conditions which is useful.
--

BJ Hargrave
Senior Technical Staff Member, IBM // office: +1 386 848 1781
OSGi Fellow and CTO of the OSGi Alliance // mobile: +1 386 848 3788
hargr...@us.ibm.com
 
 
----- Original message -----
From: Peter Kriens <peter.kri...@aqute.biz>
To: BJ Hargrave <hargr...@us.ibm.com>
Cc: via bndtools-users <bndtools-us...@googlegroups.com>, osgi-dev@mail.osgi.org
Subject: [EXTERNAL] Re: [osgi-dev] Conditional Target
Date: Wed, Jun 26, 2019 10:27
 
I was vaguely aware of this RFC but that is an extension to the DS Components isn't it? That will have more capabilities I assume since you're not restricted to the features of the current spec. 
 
This is basically a continuance of the aggregate service but with a bit smaller scope. The Aggregate Service had some basic limitations because not all components shared the same view at the same time.
 
It is a tricky area.
 
I read the RFC in detail. Kind regards,
 
Peter Kriens
 
 
 
On 26 Jun 2019, at 14:29, BJ Hargrave <hargr...@us.ibm.com> wrote:
 
 
Are you making an alternate design? Or did you not know of this RFC?
--

BJ Hargrave
Senior Technical Staff Member, IBM // office: +1 386 848 1781
OSGi Fellow and CTO of the OSGi Alliance // mobile: +1 386 848 3788
hargr...@us.ibm.com
 
 
----- Original message -----
From: Peter Kriens via osgi-dev <osgi-dev@mail.osgi.org>
Sent by: osgi-dev-boun...@mail.osgi.org
To: via bndtools-users <bndtools-us...@googlegroups.com>, osgi-dev@mail.osgi.org
Cc:
Subject: [EXTERNAL] [osgi-dev] Conditional Target
Date: Wed, Jun 26, 2019 08:26
 
I've developed a service that you can use to block the activation of a DS component until a set of other services are ready. This is related to the whiteboard pattern when the sender wants to be sure a certain set of whiteboard services are present. Normally you can only assert the properties of 1 service but this allows you to use a filter to select the aggregated properties of a group of services. An example is when you need a set of at least 3 remote services where there are at least 2 unique regions. 
 
For example, you want to block until the average of the `foo` properties on the registered Foo services is higher than 2:
 
@Reference( target="([avg]foo>=2)" )
ConditionalTarget<Foo> foos;
 
The Conditional Target object provides a direct reference to the services and service references being tracked as well as the aggregated properties. 
 
It is described in 
 
 
And you can find the binary artifact in:
 
 
Feedback appreciated on the idea and execution. If people like this, I can submit it to Apache Felix if they're interested.
 
Kind regards,
 
Peter Kriens
_______________________________________________
OSGi Developer Mail List
osgi-dev@mail.osgi.org
https://mail.osgi.org/mailman/listinfo/osgi-dev 
 
 

_______________________________________________
OSGi Developer Mail List
osgi-dev@mail.osgi.org
https://mail.osgi.org/mailman/listinfo/osgi-dev

Reply via email to