Remote Debugging Camel-K
In this article, we describe the steps needed to be able to remotely debug the Camel-K operator directly from the K8s cluster. By doing so, you are sure that the operator is executed in the same context as your target environment, which is not the case if the operator is launched on the local machine.
Publish the image
The first thing to do is to build a specific docker image of the Camel-K operator for the debug mode, indeed the kamel program will then be built without compiler optimizations, and inlining but also the docker image will launch the operator through delve to be able to remote debug it.
DEBUG_MODE=true make imagesOnce done, a docker image of type docker.io/apache/camel-k-debug:2.0.0-SNAPSHOT has been pushed into your local docker image registry.
If you are using Minikube, before executing the previous command make sure to set up properly the environment variables in your terminal by executing the command eval $(minikube -p minikube docker-env), in that case the image is directly pushed into the registry of Minikube, so you can skip the end of the section.
For other clusters like for example kind where the registry is accessible locally from localhost:5001, simply tag the image to match with the new host and port with the next command:
docker tag docker.io/apache/camel-k-debug:2.0.0-SNAPSHOT localhost:5001/apache/camel-k-debug:2.0.0-SNAPSHOTThen push the image to the target registry with the next command:
docker push localhost:5001/apache/camel-k-debug:2.0.0-SNAPSHOTTo ensure that the image has been pushed with success, let’s query the registry using the API
curl http://localhost:5001/v2/_catalog
{"repositories":["apache/camel-k-debug"]}Install the operator
Since the docker image is ready to be used, we can now install the operator with the debugging flags to make sure that the operator will be launched properly with the debug port open on its pod.
First, let’s create a namespace in which the operator will be installed, here the namespace is test.
kubectl create ns test
namespace/test createdThen, install the operator with the image that we built before
CUSTOM_IMAGE=docker.io/myrepo/camel-k CUSTOM_VERSION=2.4.0-SNAPSHOT make bundle
make install-k8s-globalIt will install the operator using apache/camel-k-debug:2.0.0-SNAPSHOT as docker image and launch it in debug mode.
Open the port on the pod
The operator is now waiting for a remote connection, but to make it possible, we need to make the debugging port accessible from outside the cluster thanks to the following port-forward command:
kubectl port-forward -n test $(kubectl get po -l app=camel-k -oname -n test) 4040:4040
Forwarding from 127.0.0.1:4040 -> 4040
Forwarding from [::1]:4040 -> 4040This command port forwards the port 4040 of the pod to the local port 4040 which makes it accessible from localhost. Where 4040 is the default port of delve configured in the pod manifest, but it can be changed when installing the operator thanks to the flag --debugging-port=4040.