Config watcher issue demo

Hi, I'm trying to implement spring cloud kubernetes in our projects. My main goals are to read configMap, secrets and enable reload using spring cloud kubernetes config watcher.

Since there are very less examples available about how to use spring cloud for kubernetes apps, I read the documentation and figured out how to read secrets and configmap from k8s. There are 2 ways you can read these i.e

Volume mount Kubernetes API The 2nd one is not recommended due to security problems which can occur so I'm preferring 1st one. But when it comes to reloading properties using watcher then there is zero examples available with spring boot 3.x.

While using below properties in bootstrap.properties I get below warning logs bootstrap.properties spring.cloud.kubernetes.discovery.enabled=false spring.cloud.kubernetes.secrets.paths=/etc/secrets/secret-k8s spring.cloud.kubernetes.secrets.fail-fast=true spring.cloud.kubernetes.secrets.enabled=true

warning log o.s.c.k.c.c.SecretsPropertySourceLocator : path support is deprecated and will be removed in a future release. Please use spring.config.import

But I couldn't find any help about how to use this property with kubernetes using volume mounts.

second thing is if possible could you please share an example of watcher with spring boot 3.x which should update mounted volume(secret/configmap) ?

build.gradle dependencies { implementation 'org.springframework.boot:spring-boot-starter-actuator' implementation 'org.springframework.boot:spring-boot-starter-web' implementation group: 'org.springframework.cloud', name: 'spring-cloud-starter-kubernetes-fabric8-config', version: '3.0.4' compileOnly 'org.projectlombok:lombok' annotationProcessor 'org.projectlombok:lombok' testImplementation 'org.springframework.boot:spring-boot-starter-test' }

To read configMap and secrets using volume mounts in Spring Cloud Kubernetes, you can follow these steps:

Mount the configMap and secret as volumes in your deployment configuration YAML file:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: your-deployment
spec:
  template:
    spec:
      volumes:
        - name: config-volume
          configMap:
            name: your-configmap
        - name: secret-volume
          secret:
            secretName: your-secret
      containers:
        - name: your-container
          image: your-image
          volumeMounts:
            - name: config-volume
              mountPath: /etc/config
            - name: secret-volume
              mountPath: /etc/secrets

In your application, use the spring.config.import property to import the mounted configMap and secret:

spring.config.import=file:/etc/config/application.properties,file:/etc/secrets/application-secrets.properties

This way, the properties from the mounted files will be loaded into your Spring Boot application.

Regarding the warning log you're seeing, it's suggesting to use spring.config.import instead of the deprecated spring.cloud.kubernetes.secrets.paths property. The updated property should look like:

spring.config.import=classpath:/etc/secrets/secret-k8s.properties

Regarding the watcher to update the mounted volumes (configMap/secret), you can use the @RefreshScope annotation in your Spring Boot application. Here's an example:

@RestController
@RefreshScope
public class MyController {

  @Value("${my.property}")
  private String myProperty;

  @GetMapping("/property")
  public String getProperty() {
    return myProperty;
  }
}

When a refresh event is triggered, the myProperty value will be updated with the latest value from the mounted volume.

Note: Make sure you have the necessary dependencies in your build.gradle file as you mentioned in your question.

ryanjbaxter / demo-bot-repo

Config watcher issue demo #3