[#AAA-170] WebServer service API cannot be injected with @OsgiService annotation

While working on c/68767 to use of the new Web API in project Neutron, I bumped into a very confusing issue which I finally was able to work around (in Patch Set 5 of c/68767), but that is worth recording here in case anyone else wants to further investigate this separately some later time, and a record just in case we run into this same issue again later when using the Web API in other projects:

It seems that the use of the @OsgiService annotation from pax-cdi-api which is useful to avoid having to manually write a BP XML with a <reference> (as documented on https://wiki.opendaylight.org/view/BestPractices/DI_Guidelines#NEW:_.40OsgiService_.26_.40OsgiServiceProvider_.28pax-cdi-api.29), does not work IFF said service is registered programmatically via an OSGi Service Factory, such as the org.opendaylight.aaa.web.WebServer was in https://git.opendaylight.org/gerrit/#/c/69475/. I have used this for other "normal" OSGi Services advertised via an @OsgiServiceProvider annotation in several places (notably infrautils but I think also some in genius and netvirt), where it did work. The link with the OSGi Service Factory based registration is more of a suspicions than something I have conclusively proven.

This seems to have something to do with this Import that gets generated in the MANIFEST.MF (of org.opendaylight.neutron.northbound-api in this case, but it's probably got nothing to do with Neutron):

[INFO] --- maven-surefire-plugin:2.18.1:test (default) @ odl-neutron-northbound-api ---
[INFO] Surefire report directory: /home/vorburger/dev/ODL/git/neutron/features/production/odl-neutron-northbound-api/target/surefire-reports

-------------------------------------------------------
 T E S T S
-------------------------------------------------------
Running org.opendaylight.odlparent.featuretest.SingleFeatureTest
Tests run: 1, Failures: 0, Errors: 1, Skipped: 0, Time elapsed: 22.34 sec <<< FAILURE! - in org.opendaylight.odlparent.featuretest.SingleFeatureTest
installFeatureCatchAndLog(org.opendaylight.odlparent.featuretest.SingleFeatureTest)[repoUrl: file:/home/vorburger/dev/ODL/git/neutron/features/production/odl-neutron-northbound-api/target/feature/feature.xml, Feature: odl-neutron-northbound-api 0.11.0.SNAPSHOT]  Time elapsed: 21.386 sec  <<< ERROR!
org.osgi.service.resolver.ResolutionException: Unable to resolve root: missing requirement [root] osgi.identity; osgi.identity=odl-neutron-northbound-api; type=karaf.feature; version="[0.11.0.SNAPSHOT,0.11.0.SNAPSHOT]"; filter:="(&(osgi.identity=odl-neutron-northbound-api)(type=karaf.feature)(version>=0.11.0.SNAPSHOT)(version<=0.11.0.SNAPSHOT))" [caused by: Unable to resolve odl-neutron-northbound-api/0.11.0.SNAPSHOT: missing requirement [odl-neutron-northbound-api/0.11.0.SNAPSHOT] osgi.identity; osgi.identity=org.opendaylight.neutron.northbound-api; type=osgi.bundle; version="[0.11.0.SNAPSHOT,0.11.0.SNAPSHOT]"; resolution:=mandatory [caused by: Unable to resolve org.opendaylight.neutron.northbound-api/0.11.0.SNAPSHOT: missing requirement [org.opendaylight.neutron.northbound-api/0.11.0.SNAPSHOT] osgi.service; effective:=active; filter:="(objectClass=org.opendaylight.aaa.web.WebServer)"]]
	at org.apache.felix.resolver.ResolutionError.toException(ResolutionError.java:42)
	at org.apache.felix.resolver.ResolverImpl.doResolve(ResolverImpl.java:391)
	at org.apache.felix.resolver.ResolverImpl.resolve(ResolverImpl.java:377)
	at org.apache.felix.resolver.ResolverImpl.resolve(ResolverImpl.java:349)
	at org.apache.karaf.features.internal.region.SubsystemResolver.resolve(SubsystemResolver.java:218)
	at org.apache.karaf.features.internal.service.Deployer.deploy(Deployer.java:291)
	at org.apache.karaf.features.internal.service.FeaturesServiceImpl.doProvision(FeaturesServiceImpl.java:1248)
	at org.apache.karaf.features.internal.service.FeaturesServiceImpl.lambda$doProvisionInThread$1(FeaturesServiceImpl.java:1147)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)


Results :

Tests in error: 
  Unable to resolve root: missing requirement [root] osgi.identity; osgi.identity=odl-neutron-northbound-api; type=karaf.feature; version="[0.11.0.SNAPSHOT,0.11.0.SNAPSHOT]"; filter:="(&(osgi.identity=odl-neutron-northbound-api)(type=karaf.feature)(version>=0.11.0.SNAPSHOT)(version<=0.11.0.SNAPSHOT))" [caused by: Unable to resolve odl-neutron-northbound-api/0.11.0.SNAPSHOT: missing requirement [odl-neutron-northbound-api/0.11.0.SNAPSHOT] osgi.identity; osgi.identity=org.opendaylight.neutron.northbound-api; type=osgi.bundle; version="[0.11.0.SNAPSHOT,0.11.0.SNAPSHOT]"; resolution:=mandatory [caused by: Unable to resolve org.opendaylight.neutron.northbound-api/0.11.0.SNAPSHOT: missing requirement [org.opendaylight.neutron.northbound-api/0.11.0.SNAPSHOT] osgi.service; effective:=active; filter:="(objectClass=org.opendaylight.aaa.web.WebServer)"]]

Tests run: 1, Failures: 0, Errors: 1, Skipped: 0

[INFO] ------------------------------------------------------------------------
[INFO] Reactor Summary:
[INFO] 
[INFO] ODL :: neutron :: project-neutron-parent ........... SUCCESS [  5.379 s]
[INFO] ODL :: neutron :: model ............................ SUCCESS [ 30.068 s]
[INFO] ODL :: neutron :: neutron-spi ...................... SUCCESS [ 14.721 s]
[INFO] ODL :: neutron :: northbound-api ................... SUCCESS [ 16.400 s]
[INFO] ODL :: neutron :: transcriber ...................... SUCCESS [ 11.843 s]
[INFO] ODL :: neutron :: neutron-logger ................... SUCCESS [  3.693 s]
[INFO] Neutron Artifacts .................................. SUCCESS [  0.252 s]
[INFO] OpenDaylight :: Neutron :: API ..................... SUCCESS [ 31.421 s]
[INFO] OpenDaylight :: Neutron :: Northbound .............. FAILURE [ 29.459 s]
[INFO] OpenDaylight :: Neutron :: Service ................. SKIPPED
[INFO] ODL :: neutron :: neutron-hostconfig-utils ......... SKIPPED
[INFO] ODL :: neutron :: neutron-hostconfig-ovs ........... SKIPPED
[INFO] OpenDaylight :: Neutron :: Hostconfig :: OVS ....... SKIPPED
[INFO] ODL :: neutron :: neutron-hostconfig-vpp ........... SKIPPED
[INFO] OpenDaylight :: Neutron :: Hostconfig :: VPP ....... SKIPPED
[INFO] features-neutron-service ........................... SKIPPED
[INFO] OpenDaylight :: Neutron :: Logger .................. SKIPPED
[INFO] features-aggregator ................................ SKIPPED
[INFO] ODL :: neutron :: integration-test-standalone ...... SKIPPED
[INFO] OpenDaylight :: Neutron :: Logger :: Test .......... SKIPPED
[INFO] features-neutron-test .............................. SKIPPED
[INFO] features-test-aggregator ........................... SKIPPED
[INFO] neutron-karaf ...................................... SKIPPED
[INFO] ODL :: neutron :: integration-test ................. SKIPPED
[INFO] ODL :: neutron :: neutron-hostconfig ............... SKIPPED
[INFO] neutron ............................................ SKIPPED
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 02:27 min
[INFO] Finished at: 2018-03-16T00:25:38+01:00
[INFO] Final Memory: 199M/1836M
[INFO] ------------------------------------------------------------------------

[AAA-170] WebServer service API cannot be injected with @OsgiService annotation Created: 16/Mar/18 Updated: 16/Mar/18
Status:	Open
Project:	aaa
Component/s:	None
Affects Version/s:	None
Fix Version/s:	None

[AAA-170] WebServer service API cannot be injected with @OsgiService annotation Created: 16/Mar/18 Updated: 16/Mar/18