Explain the purpose and working principle of the ConfigMap object in Kubernetes

A ConfigMap in Kubernetes is used to store configuration data as key-value pairs, which can be used by containers in pods.

Main tasks of ConfigMap:

• Separating configuration from the container image to avoid rebuilding the image when settings change.
• Allowing dynamic configuration changes without modifying the code.

Principle of operation:

• ConfigMap is created as a Kubernetes object containing configuration data.
• In pods, ConfigMap can be mounted as files in volumes or passed as environment variables.
• Containers access this data and use it to configure their behavior.

Example of creating a ConfigMap and using it in a pod:

apiVersion: v1
kind: ConfigMap
metadata:
  name: example-config
data:
  APP_MODE: "production"
  LOG_LEVEL: "info"
---
apiVersion: v1
kind: Pod
metadata:
  name: example-pod
spec:
  containers:
  - name: app
    image: myapp:latest
    envFrom:
    - configMapRef:
        name: example-config

Thus, ConfigMap provides a convenient way to manage application configuration in Kubernetes.