I just looked into the camel-scr component.
If found some design issues:
- Why do we need to @Reference to ComponentResolver. I think we should
do this under the covers so the user does not have to configure it himself.
The easiest way would probably be to do this using plain OSGi APIs.
- It seems the context start is delayed when additional components are
found. This seems to be a bit fragile as the delay means we can miss
components.
In the case of camel blueprint we go into GracePeriod and specify which
component we are missing. For SCR I think the correct way would be to
only start after all required components are present. Not sure if this
is easy to do though. In any case I think the problem of depending on
components and only starting once they are there is a general problem
that should be solved outside camel blueprint or camel scr.
- If component auto detection does not work we could create a custom
camel annotation @RequiresComponent("<component name>") and
@RequiresCompoents. So people could annotate their concrete context
class with all components they need.
- I think the direct injection of properties into RouteBuilders should
not be done. Or at least not by default. Instead I would by default let
the user do the injection in getRouteBuilders. At least we could use the
@Inject annotation to mark properties that are meant for injection
perhaps even with @Named so the user can specify the name.
I can help with implementing some of my proposals. I will wait for more
comments and discussions though.
Christian
On 09.11.2014 09:42, Claus Ibsen wrote:
Hi
There is a great contribution for a new camel-scr module that allows
end users to use OSGi declarative services instead of spring-dm /
blueprint.
The code has just been pushed to master branch, but there is still
some work to finish and polish the code.
But I wanted to bring this to attention, so we can have more eyes on
this - especially for the OSGi folks.
The JIRA ticket is, with some bullets to look at:
https://issues.apache.org/jira/browse/CAMEL-7997
And the code is in the camel-scr module. And there is a camel-scr
feature to install the module.
--
Christian Schneider
http://www.liquid-reality.de
Open Source Architect
http://www.talend.com
