Cannot set liberty debug port

[sdehors-ibm]

I'm trying to set the liberty debug port as explained here: https://github.com/OpenLiberty/ci.maven/blob/main/docs/debug.md
but when the liberty server starts, it adds automatically 2 lines at the end of the server.env which take precedence over the line I've added.

WLP_DEBUG_SUSPEND=n
WLP_DEBUG_ADDRESS=54690

This behaviour seems consistant with the code in DevUtil.java but not with the documentation. It seems it's not possible to set the debug port which is a bug according to the doc.

[cherylking]

I don't think that documentation is taking into account the use of dev mode. Are you starting the server with the dev goal?

[sdehors-ibm]

yes the server is started with dev mode

[cherylking]

So I think that documentation just needs to be updated to clarify that it is relevant for the start and run goals, not the dev goal. And then add some info on how to debug in dev mode. Thank you for pointing this out.

[sdehors-ibm]

It's quite annoying though that we cannot set the debug port in dev mode. For our project the port 7777 is not available so debugging requires to find the random debug port and specifically attach to it at every restart of liberty.

[cherylking]

@sdehors-ibm Are you familiar with Liberty Tools (available in Eclipse, VSCode and IntelliJ IDEA) which helps manage your apps in development and the Liberty servers and handles attaching the debugger for you?

[TrevCraw]

Hi @sdehors-ibm , you should be able to set the debug port for dev mode using the debugPort dev mode parameter on the command line: https://github.com/OpenLiberty/ci.maven/blob/main/docs/dev.md#additional-parameters. For instance:

mvn liberty:dev -DdebugPort=1234

[cherylking]

@sdehors-ibm Please confirm that you can set the debug port as Trevor indicated. If so, I will simply use this issue to update the documentation for the debug goal to make it more clear.

[sdehors-ibm]

Thanks @TrevCraw , it is what I was looking for.

@cherylking, we do use Liberty tools and we initially looked into setting the debug port manually to workaround OpenLiberty/liberty-tools-vscode#544.