I am currently facing a problem of how to dynamically "wire" OSGi Services depending on their configuration properties. I want to do that with Declarative Services.
To give a concrete example: I have two different OSGi Services A and B which both are ManagedServiceFactories and require configuration. So I can have multiple instances of A and multiple instances of B each with separate configurations.
I use Felix FileInstall, DS/SCR and BNDTools and my configs look like this (simplified):
a-one.cfg: b.id = foo
a-two.cfg: b.id = bar
b-one.cfg: id = foo
b-two.cfg: if = bar
Now I want to wire/bind service b-one to a-one and service b-two to a-two (depending on their matching configuration properties b.id = id).
Currently I can see two approaches on how to achieve this:
- Bind all available instances of Service B to the instances of Service A and select the proper Service B depending on its id.
- Implement an own ManagedServiceFactory for Service A which creates an LDAP filter to find the proper instance of Service B.
For solution 1.) I do not like that I need to bind all instances of Service B to every instance of Service A. I like to only bind the instance of Service B which meets my configuration property constraint.
For solution 2.) I do not like that I need to dig to the lower levels: own ManagedServiceFactory and bypassing DS by manually find the proper (LDAP filtered) Service instance.
Do anyone know a better solution or "best practice" how to achieve that? I am not sure if maybe the WireAdmin spec can help me here?
Solution with BNDTools/BND Annotation would be welcomed ;)