env

apiVersion: v1
kind: Pod
metadata:
  name: app-pod
spec:
  containers:
    - name: app-pod
      image: app-pod
      ports:
        - contaierPort: 80
      env:
      - name: DB_NAME
        value: mysql 

Type

• plain key value ```yaml env:
  • name: DB_NAME value: mysql ```
• configMap
  • Create a configMap:
    • Imperative way: kubectl create configmap
      • from literal:

          kubectl create configmap \
          <config_name> --from-literal=<key>=<value>`
        

      • from file:

          kubectl create configmap \
          <config_name> --from-file=<path-to-file>`
        

    • Declarative way: kubectl create -f

        apiVersion: v1
        kind: ConfigMap
        metadata:
      name: app-config
        data:
      DB_NAME: mysql 
      ENV: prod
      

  • ConfigMap in Pod: ```yaml env:
  • name: DB_NAME valueFrom: configMapKeyRef ```
  • Command:
    • Get: kubectl get configmaps
    • Describe: kubectl describe configmaps
• secret
  • Create a secret:
    • Imperative way: kubectl create secret generic
      • from literal: ```bash kubectl create secret generic\
      --from-literal==` ``` - from file: ```bash kubectl create secret generic\ --from-file=` ```
    • Declarative way: kubectl create -f
      • Convert data into hash:

          echo -n "pwd" | base64
        

      • Put hash into yaml

          apiVersion: v1
          kind: secret
          metadata:
        name: app-secret
          data:
        DB_Host: <hash> 
        DB_User: <hash>
        DB_Password: <hash>
        

  • Secret in Pod: ```yaml env:
    • name: DB_Host valueFrom: secretKeyRef ```
  • Command:
    • Get: kubectl get secrets
    • Describe: kubectl describe secrets
    • To yaml: kubectl get secret <secret_name> -o yaml
    • Decode hash:

        echo -n "<hash>" | base64 --decode
      

• Security Context
  • You can write in pod or container level.
  • Priority: container > pod

      apiVersion: v1
      kind: Pod
      metadata:
        name: pod
      spec:
        securityContext: <-- pod level
          runAsUser: 1000
        containers:
            - name: ubuntu
              image: ubuntu
              command: ["echo", "hi"]
                securityContext: <-- container level
                  runAsUser: 1000
                  capabilities:  <-- container level only
                      add: ["MAC_ADMIN"]