felix-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Tuomas Kiviaho (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (FELIX-4847) Allow TemporalServiceDependency to be optional
Date Wed, 29 Apr 2015 07:50:06 GMT

    [ https://issues.apache.org/jira/browse/FELIX-4847?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14518923#comment-14518923
] 

Tuomas Kiviaho commented on FELIX-4847:
---------------------------------------

Pretty much, because I'm trying to hide the details of this kind of approach by dressing it
as temporal service :-) 

Instead of Latch I had ServiceTracker doing the same thing but the amount of glue was about
the same (foobar+latch=st, bind=st.addingService, latch.await=st.waitForService). I just wanted
to get rid of this glue once and for all, because this pattern emerges every single time I
have dealing directly with ConfigurationAdmin and the way it's been implemented (asynch only
causing potential race conditions).

> Allow TemporalServiceDependency to be optional
> ----------------------------------------------
>
>                 Key: FELIX-4847
>                 URL: https://issues.apache.org/jira/browse/FELIX-4847
>             Project: Felix
>          Issue Type: Wish
>          Components: Dependency Manager
>    Affects Versions: dependencymanager-3.2.0
>            Reporter: Tuomas Kiviaho
>         Attachments: TemporalServiceDependencyImpl.java, dm.test.with.bndtools.tgz, dm.test.with.maven.tgz
>
>
> I wanted to use temporal service to wait for CM update thread to finish what it's doing
(because the spec doesn't have a non-parallel version). 
> Everything worked fine until JUnit test rule said that the component isn't ready yet.
I was merely checking that every required dependency was also available and to my surprise
the temporal service was marked unavailable until the CM had completed what it was doing.
> 1) Shouldn't temporal service be always available externally via available property and
keep track on the actual state only internally? This approach might not be backwards compatible.
> 2) Could temporal service be allowed to be marked as optional. This would suit my use
case, but it feels like a 'golden hammer' approach because it alters component's state machine
behavior a bit which in turn can be harmful for other use cases. 
> As a workaround I'd have to differentiate the dependencies somehow from each other, but
I see that the 4.x has removed the dedicated interface that I was thinking of relying upon
to. 



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Mime
View raw message