✅ add support for Windows

[ryandens]

No description provided.

[pixee-ryandens]

Nice work! ✅ I analyzed your pull request and don't see any hardening opportunities.

[neboskreb]

@ryandens this PR seems a bit stuck. Would you like some assistance? I'd gladly help to move it forward.

[ryandens]

@neboskreb feel free! i just rebased it with main. I don't have a windows machine accessible, so getting the integration tests to pass on windows is a bit painful.

[neboskreb]

I fixed a couple of very small bugs and it seems to work for me.

@ryandens I'd push my changes if you add me to the collaborators

[neboskreb]

@ryandens I found a way to push my commits without pushing :) Created PR #298 to "push" those 2 commits into this branch - please see and merge.

[neboskreb]

My investigation finds that the test failures in #298 come from IllegalArgumentException thrown from the internals of Java Instrumentation, probably triggered by an error condition inside or around the OpenTelemetryAgent:

Hello from my simple agent!
ERROR io.opentelemetry.javaagent.OpenTelemetryAgent
java.lang.IllegalArgumentException
	at java.instrument/sun.instrument.InstrumentationImpl.appendToClassLoaderSearch0(Native Method)
	at java.instrument/sun.instrument.InstrumentationImpl.appendToBootstrapClassLoaderSearch(InstrumentationImpl.java:276)
	at io.opentelemetry.javaagent.OpenTelemetryAgent.installBootstrapJar(OpenTelemetryAgent.java:98)
	at io.opentelemetry.javaagent.OpenTelemetryAgent.startAgent(OpenTelemetryAgent.java:56)
	at io.opentelemetry.javaagent.OpenTelemetryAgent.premain(OpenTelemetryAgent.java:46)
	at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:104)
	at java.base/java.lang.reflect.Method.invoke(Method.java:565)
	at java.instrument/sun.instrument.InstrumentationImpl.loadClassAndStartAgent(InstrumentationImpl.java:544)
	at java.instrument/sun.instrument.InstrumentationImpl.loadClassAndCallPremain(InstrumentationImpl.java:556)

Unfortunately, the exact cause of the exception is not know because OpenTelemetryAgent does not do a best job logging it, showing only the topmost layer and not printing the "caused by" part.

This error occurs only in test configuration, whereas the run configuration completes successfully.

Bumping up the version from 1.11.1 to the newest 1.23.0 brought no relief.

Also, no errors occur in test configuration if a different agent is used, for instance org.mockito:mockito-core:5.21.0 - in this case the test shows no malfunction.

@ryandens This looks to me like an Open Telemetry setup issue on Windows (or my machine?). Unfortunately, I'm not familiar with the framework. If you are, could you give me some hints to what could be wrong?

[ryandens]

Unfortunately, I also don't know what the issue was here - I also saw test failures in the javaagent-application plugin project, so I don't think this is isolated to the OpenTelemetry instrumentation agent. I could of course be mistaken. Thanks for your work on this issue, it looks like it brought it closer to the finish line.