Restore Kubernetes functionalities

[davgia]

I deploy several Steeltoe-based (v3) aspnetcore .net8 microservices on Kubernetes (v1.35). In a cluster the service discovery is native so it is not required client-side. But, the ability to read configmap and secrets is a must have.
Configmap can be read through the api (still the preferred choice), alternatively they can be mounted as files (so it is transparent to the service). On the other end, secrets should be mounted in the pod and read from it (see: #976), so no api call is required to use them but the framework need to support the file structure.

Example (java spring boot):

apiVersion: apps/v1
kind: Deployment
metadata:
  name: test-service
spec:
  template:
    spec:
      containers:
      - env:
        - name: SPRING_CLOUD_KUBERNETES_SECRETS_PATHS
          value: /etc/secrets/test-service
        image: test-service:1.0.0
        volumeMounts:
        - mountPath: /etc/secrets/test-service
          name: test-service-volume
          readOnly: true
      volumes:
      - name: test-service-volume
        secret:
          defaultMode: 420
          secretName: test-service

apiVersion: v1
kind: Secret
type: Opaque
metadata:
  name: test-service
  namespace: test
stringData:
  jdbc.test.jdbc-url: jdbc:sqlserver://localhost:1433;databaseName=Test;Encrypt=true;TrustServerCertificate=true;
  jdbc.test.password: ***
  jdbc.test.username: ***
  spring.rabbitmq.password: ***

# see folder structure
$ ls -alh /etc/secrets/test-service/
total 4K
drwxrwxrwt    3 root     root         160 Mar 23 14:06 .
drwxr-xr-x    3 root     root        4.0K Mar 23 14:11 ..
drwxr-xr-x    2 root     root         120 Mar 23 14:06 ..2026_03_23_14_06_16.2737885139
lrwxrwxrwx    1 root     root          32 Mar 23 14:06 ..data -> ..2026_03_23_14_06_16.2737885139
lrwxrwxrwx    1 root     root          56 Mar 23 14:06 jdbc.test.jdbc-url -> ..data/jdbc.test.jdbc-url
lrwxrwxrwx    1 root     root          56 Mar 23 14:06 jdbc.test.password -> ..data/jdbc.test.password
lrwxrwxrwx    1 root     root          56 Mar 23 14:06 jdbc.test.username -> ..data/jdbc.test.username
lrwxrwxrwx    1 root     root          31 Mar 23 14:06 spring.rabbitmq.password -> ..data/spring.rabbitmq.password
# see file content
$ cat /etc/secrets/test-service/spring.rabbitmq.password
pb[REDACTED]m7/app $

So, spring has the ability to read each file inside the directory and uses the filename as key and its content as the value and injects it into the application configuration.

For me the Steeltoe's Kubernetes package can "just" have the following features:

• injects cluster information in the info actuator
• provides additional health endpoints: liveness and readiness
• can read configmap from kubernetes api
• can read secrets mounted inside the pod

If necessary I can contribute.

Thanks!

[TimHess]

As the original implementer of this functionality, I was disappointed when we removed it from Steeltoe, but I am happy that you have found it useful!

Unfortunately, the core Steeltoe team does not currently have the capacity to support an additional platform (team members haven't been actively working with Kubernetes for several years already), and maintaining the packages under the Steeltoe umbrella would add some level of responsibility that we aren't able to take on at this point in time. The Spring team is much larger and the community is very engaged - that's how they're able to maintain so many projects.

We'll keep this issue open for others to weigh in (and I hope readers do, even if it's just a reaction on the post), but I don't see how we would be able to appropriately support this effort at this time.

[davgia]

I understand, I will probably reimplement it myself then.

[davgia]

Hi @TimHess,

I have a question: in Steeltoe 4 if I define an httpclient with ServiceDiscovery can I still have it resolve normally? I mean I do not have eureka or something else, I'm in a kubernetes cluster so I would like to simply resolve service names. Can I do that? I don't quite understand the purpose of the kubernetes discovery client in steeltoe 3. Thanks!