Kubernetes - ConfigMaps 🗺️

Description 👀

ConfigMap is a Kubernetes object that provides a way to store configuration data in key-value pairs. They allow you to decouple configuration artifacts from your container images, which enables you to modify the configuration data without rebuilding and repdeploying your containers. Just like everything else in Kubernetes there are two ways to create a ConfigMap. You can either use the kubectl command or you can use a ConfigMap definition.

• example at yaml-examples/configmap-description.yaml

To tie a ConfigMap to a Pod you can use the envFrom or env section of the Pod definition.

• example at yaml-examples/configmap-pod.yaml

Basic Commands 📝

• create a ConfigMap using the kubectl command,

    kubectl create configmap <configmap-name> --from-literal=<key>=<value>
  

• create a ConfigMap using a definition,

    kubectl create configmap <configmap-name> --from-file=<path-to-file>
  

• get a ConfigMap

    kubectl get configmap <configmap-name>
  

• describe a ConfigMap

    kubectl describe configmap <configmap-name>
  

• delete a ConfigMap

    kubectl delete configmap <configmap-name>
  

Examples 🧩

• sample ConfigMap

    APP_COLOR: blue
    APP_MODE: production
  

• sample ConfigMap definition

    apiVersion: v1
    kind: ConfigMap
    metadata:
        name: sample-config
    data:
        APP_COLOR: blue
        APP_MODE: production
  

• sample Pod definition

    apiVersion: v1
    kind: Pod
    metadata:
        name: configmap-pod
    spec:
        containers:
          - name: configmap-container
            image: nginx
            ports:
              - containerPort: 80
            envFrom:
              - configMapRef:
                    name: sample-config
  

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