Remote Debugging Quarkus

[s3nu4]

Hey,

I updated my Keycloak installation from 16 (WildFly) to 18 (Quarkus). Until the update I was able to debug my custom SPI extensions with remote debugging in IntelliJ. I just had to add the DEBUG: "true" and DEBUG_PORT: "*:8787" to my docker-compose setup.

I know that the framework has changed to Quarkus and the way to remote debug has probably changed, but I can't find out how to do this with Keycloak 18.

Do you have any advices how to enable remote debugging?

Thank you!

[MetroMarv]

Actually I was also not able to find any documentation on this. Also kc.sh --help does not list any configuration options on debugging.

However this article https://blog.codecentric.de/en/2021/12/keycloak-keycloak-x/ says the you need to use the --debug flag when starting the Keycloak. And additionally specify the env var DEBUG_PORT='*:8787'. This also worked for me.

[MetroMarv]

Actually the quarkus docs give some more insight on debugging

[martin-kanis]

@DGuhr @pedroigor Guys, I think we should add information about Quarkus remote debugging into the help and to the docs if is not there? WDYT?

[DGuhr]

Sure. We haven't started writing developer guides yet, always fell down the road due to other priorities. Feel free to create an issue :)

For other people landing here, to remote debug, do the following:

start Keycloak using kc.<sh|bat> --debug <start|build|start-dev> ...
a remote debugging session will be initiated using port 8787 by default.

Some options:

• to suspend your debugging session, you can set an environment variable -> export DEBUG_SUSPEND=y
• to set the port, use the env var -> export DEBUG_PORT=<port>
  • to be able to remote debug a containerized keycloak, set the port to export DEBUG_PORT=*:<port>

When a build is invoked as part of the server startup (so not using --optimized and having some changes that trigger a rebuild), another JVM is spawned internally, so your debug session will be killed when the build is done and we're back in the "runtime" vm. make sure to reconnect after the build process is done. Best to do with the suspend flag ;)

[SangI762]

Thanks, it worked.

[martin-kanis]

Here is the issue #13513
Thank you for explaining the fact, why I need to connect my debugger twice :)

[jsorah]

Throwing another way to get this with a containerized run using podman (should work for docker too):

podman run -p 8080:8080 -p 8443:8443 -p <port>:<port> -e DEBUG_PORT='*:<port>' -e KEYCLOAK_ADMIN=admin -e KEYCLOAK_ADMIN_PASSWORD=admin quay.io/keycloak/keycloak:19.0.1 --debug start-dev

and then attach your debugger to <port> where <port> is your desired debug port.

[EvgeniGordeev]

here is an example Maven project to debug Quarkus KC easily in an IDE.

NB: Using production start instead of start-dev helps to avoid connecting the debugger twice.