Hi Guillaume, thank you for your reply. In this special case it is about an implementation for "javax.xml.parsers.SAXParserFactory" and a service for that. The bundle "org.eclipse.equinox.registry" (I need to use to satisfy third party dependencies) is using a tracker to find an implementation and prints errors to stdout if there is no one. To prevent that messages on every Karaf start I would like to have such a service in the Karaf instance.
The Equinox OSGi framework provides that service itself. Without any provide capability in its manifest. The Apache Felix OSGi framework doesn't provide such a service. So, what are the options: add it to "org.osgi.framework.system.capabilities" IMHO this will be not correct, because the service is present if Equinox is used and not present if Felix is used. Use "conditionals" in a feature to install another bundle that provides a "javax.xml.parsers.SAXParserFactory" service if Felix is used (and so the conditional will skip the installation if Equinox is used). If my reading has been correct, conditionals could be used for installed features and not for the special OSGi framework implementation. I can install another bundle / feature that provides that service implementation for both frameworks. This is okay, but if it is not necessary... So, is there a simple method to leave it up to the user to switch between "karaf.framework" Felix or Equinox and handle that in some way, so another implementation is installed only if not Equinox is choosen? Best regards, Markus 2017-02-06 8:45 GMT+01:00 Guillaume Nodet <gno...@apache.org>: > You can modify the etc/config.properties file, in particular the > org.osgi.framework.system.capabilities > configuration. If some service are provided by default by the framework and > are missing, > you may want to raise a JIRA issue and provide a patch / pull request. > > 2017-02-05 12:05 GMT+01:00 Markus Rathgeb <maggu2...@gmail.com>: >> >> Ah, okay, I assume it is caused by the missing >> Provide-Capability of the Equinox bundle that it provides that service. >> Could this information be added by some configuration file without >> modify the Equinox bundle itself? >> >> 2017-02-05 11:49 GMT+01:00 Markus Rathgeb <maggu2...@gmail.com>: >> > Hello, >> > >> > I thought I understand how the dependency flag is working for features >> > and bundles, but at least it seems to be different. >> > Perhaps someone could explain me the following scenario: >> > >> > Feature file: >> > === >> > <?xml version="1.0" encoding="UTF-8"?> >> > <features name="saxparserfactory" >> > xmlns="http://karaf.apache.org/xmlns/features/v1.4.0";> >> > >> > <feature name="saxparserfactory" version="1.0-SNAPSHOT"> >> > >> > <requirement>osgi.service;filter:="(objectClass=javax.xml.parsers.SAXParserFactory)";effective:=active</requirement> >> > <feature dependency="true">jboss-xerces</feature> >> > </feature> >> > >> > <feature name="jboss-xerces" description="JBoss Xerces" >> > version="1.0-SNAPSHOT"> >> > <details>OSGi service for >> > 'javax.xml.parsers.SAXParserFactory'</details> >> > >> > <!-- Maven repository: >> > https://repository.jboss.org/nexus/content/repositories/releases/ --> >> > <!-- <bundle >> > >> > start-level="30">mvn:org.jboss.osgi.xerces/jbosgi-xerces/3.1.0.Final</bundle> >> > --> >> > <bundle >> > start-level="30">https://repository.jboss.org/nexus/content/repositories/releases/org/jboss/osgi/xerces/jbosgi-xerces/3.1.0.Final/jbosgi-xerces-3.1.0.Final.jar</bundle> >> > >> > <capability>osgi.service;objectClass=javax.xml.parsers.SAXParserFactory</capability> >> > >> > <bundle dependency="true" >> > start-level="30">mvn:org.osgi/org.osgi.util.xml/1.0.1</bundle> >> > <bundle dependency="true" >> > start-level="8">mvn:org.ops4j.pax.logging/pax-logging-api/1.9.1</bundle> >> > </feature> >> > >> > </features> >> > === >> > >> > I would expect if I install the feature "saxparserfactory" the feature >> > jboss-xerces is installed only if the requirements are not already >> > fulfilled. >> > The only requirement the feature drops in should be to ensure that >> > there is a SAXParserFactory service available. >> > Should this be possible? >> > >> > >> > Test >> > === >> > >> > I used the current Karaf 4.1.0 form the second voting round. >> > >> > Start a clean instance: >> > $ bin/karaf clean >> > >> > As expected Apache Felix is the used OSGi framework >> > >> > karaf@root()> bundle:list -t 0 -s 0 | grep Active >> > 0 │ Active │ 0 │ 5.6.1 │ org.apache.felix.framework >> > >> > I added the feature repository file. >> > >> > karaf@root()> feature:repo-add >> > file:///home/maggu2810/tmp/saxparserfactory-feature.xml >> > Adding feature url >> > file:///home/maggu2810/tmp/saxparserfactory-feature.xml >> > >> > After that let's look if there is already a SAXParserFactory present: >> > >> > karaf@root()> service:list javax.xml.parsers.SAXParserFactory >> > >> > No output, so as expected, no service found. >> > >> > Check what will be done if the feature is installed: >> > >> > karaf@root()> feature:install -t -v saxparserfactory >> > Adding features: saxparserfactory/[1.0.0.SNAPSHOT,1.0.0.SNAPSHOT] >> > Changes to perform: >> > Region: root >> > Bundles to install: >> > >> > https://repository.jboss.org/nexus/content/repositories/releases/org/jboss/osgi/xerces/jbosgi-xerces/3.1.0.Final/jbosgi-xerces-3.1.0.Final.jar >> > mvn:org.osgi/org.osgi.util.xml/1.0.1 >> > >> > This is as I expect what should be done. >> > >> > Let's exit the Karaf container. >> > >> > karaf@root()> shutdown -f >> > >> > >> > >> > After that I used the Equinox framework >> > >> > $ echo 'karaf.framework=equinox' >> etc/custom.properties >> > >> > and started again a clean isntance. >> > >> > $ bin/karaf clean >> > >> > Ensure the feature repository is available: >> > >> > karaf@root()> feature:repo-add >> > file:///home/maggu2810/tmp/saxparserfactory-feature.xml >> > Adding feature url >> > file:///home/maggu2810/tmp/saxparserfactory-feature.xml >> > >> > The Equinox OSGi framework bundle already provides a SAXParserFactory >> > service. >> > >> > karaf@root()> service:list javax.xml.parsers.SAXParserFactory >> > [javax.xml.parsers.SAXParserFactory] >> > ------------------------------------ >> > service.pid = >> > 0.org.eclipse.osgi.internal.framework.XMLParsingServiceFactory >> > service.vendor = Eclipse.org - Equinox >> > service.id = 20 >> > service.bundleid = 0 >> > service.scope = bundle >> > Provided by : >> > OSGi System Bundle (0) >> > >> > Now I would expect that the installation of the saxparserfactory >> > feature will not trigger an installation of the jboss-xerces feature, >> > because all requirements should be already satisfied. >> > But it looks like: >> > >> > karaf@root()> feature:install -t -v saxparserfactory >> > Adding features: saxparserfactory/[1.0.0.SNAPSHOT,1.0.0.SNAPSHOT] >> > Changes to perform: >> > Region: root >> > Bundles to install: >> > >> > https://repository.jboss.org/nexus/content/repositories/releases/org/jboss/osgi/xerces/jbosgi-xerces/3.1.0.Final/jbosgi-xerces-3.1.0.Final.jar >> > mvn:org.osgi/org.osgi.util.xml/1.0.1 >> > >> > What am I doing wrong? >> > >> > Best regards, >> > Markus Rathgeb > > > > > -- > ------------------------ > Guillaume Nodet >
