Netty/Karaf integration test suite

This directory contains a simple test to ensure Netty bundles can be resolved in an Apache Karaf environment.

Design

This test is structured as a Karaf Feature, hosted in src/main/feature/feature.xml, which lists tested budles and contains instructions for karaf-maven-plugin to build an Karaf Archive. This includes a quick test ensuring the bundles can be resolved in a plain Karaf environment when run with maven.compiler.target.

Please note that both pom.xml and feature.xml need to be list the bundles to be verified. The former ensures the bundle is built before test and the latter ensures it is tested.

Diagnostics

A typical failure without mvn -e looks like this:

[ERROR] Failed to execute goal org.apache.karaf.tooling:karaf-maven-plugin:4.4.8:verify (default-verify) on project testsuite-karaf: Verification failures: Verification failures:
[ERROR]         Feature resolution failed for [test/4.2.5.Final-SNAPSHOT]
[ERROR] Message: Unable to resolve root: missing requirement [root] osgi.identity; osgi.identity=test; type=karaf.feature; version=4.2.5.Final-SNAPSHOT; filter:="(&(osgi.identity=test)(type=karaf.feature)(version>=4.2.5.Final-SNAPSHOT))" [caused by: Unable to resolve test/4.2.5.Final-SNAPSHOT: missing requirement [test/4.2.5.Final-SNAPSHOT] osgi.identity; osgi.identity=io.netty.buffer; type=osgi.bundle; version="[4.2.5.Final-SNAPSHOT,4.2.5.Final-SNAPSHOT]"; resolution:=mandatory [caused by: Unable to resolve io.netty.buffer/4.2.5.Final-SNAPSHOT: missing requirement [io.netty.buffer/4.2.5.Final-SNAPSHOT] osgi.wiring.package; filter:="(osgi.wiring.package=jdk.jfr)"]]
[ERROR] Repositories: {
[ERROR]         file:/home/nite/prj/netty/testsuite-karaf/target/feature/feature.xml
[ERROR]         mvn:org.apache.karaf.features/framework/4.4.8/xml/features
[ERROR] }
[ERROR] Resources: {
[ERROR]         mvn:io.netty/netty-buffer/4.2.5.Final-SNAPSHOT
[ERROR]         mvn:io.netty/netty-common/4.2.5.Final-SNAPSHOT
[ERROR]         mvn:io.netty/netty-resolver/4.2.5.Final-SNAPSHOT
[ERROR] }

Here the Message shows the underlying problem, but it is a bit hard to read, because it is encoding an causality stack. The last part indicates what went wrong:

Unable to resolve io.netty.buffer/4.2.5.Final-SNAPSHOT: missing requirement [io.netty.buffer/4.2.5.Final-SNAPSHOT] osgi.wiring.package; filter:="(osgi.wiring.package=jdk.jfr)"

What this is telling us is that netty-buffer cannot be installed because it requires the jdk.jfr Java package, which is not provided by Karaf.

Note that the filter part looks simple above, but can look quite arcane, perhaps like

filter:="(&(osgi.ee=JavaSE)(version=1.8))"

This is not that difficult, as it really is just an RFC1960 LDAP search filter. As such, it is using Polish Notation to say that the execution environment needs to be compatible with JavaSE-1.8.