Vaadin 12 OSGi startup issue within Karaf framework

[RaimundBarbeln]

We have an issue with OSGi and Vaadin 12 we face when deploying a Vaadin-based UI bundle in Karaf 4.1.7. The issue is also described in the forum in following post: https://vaadin.com/forum/thread/17461537/bundlefilterinitializer-not-found-when-starting-vaadin-application-in-karaf.

When starting the bundle in Karaf, we always face the following problem:

java.util.ServiceConfigurationError: com.vaadin.flow.server.VaadinServiceInitListener: Provider com.vaadin.flow.server.startup.BundleFilterInitializer not found

Independent from how the Servlet is registered at the OSGi http service (http whiteboard as in the Vaadin OSGi starter project, or via @WebServlet annotation in a servlet class derived from VaadinServlet).

When starting the OSGi-Starter-Projekt from the Vaadin page (which starts a felix configuration), it works. Possibly it has to do with the detection of the BundleFilterInitializer via Java SPI (the felix configuration includes also a number of spifly bundles), but I’m not sure about this. The org.apache.aries.spifly.dynamic.bundle is also available in our Karaf environment.

[pleku]

I'm going to merge this issue into #6525 which is a later issue but for 14 and considered as an enhancement at this point.