deployment.yaml

# 1. Create a secrets config file (eg: deployment-secrets.yaml)
# 2. Run the kubectl apply -f deployment-secrets.yaml
# 3. Create the deployment.yaml file and add configs to it as belows and refer the secrets
# 4. Now run kubectl apply -f deployment.yaml for running the pod with the applied secrets
apiVersion: apps/v1
kind: Deployment
metadata:
  name: mongo-deployment
  labels:
    app: mongodb
spec:
  replicas: 1
  selector:
    matchLabels:
      app: mongodb
  template:
      metadata:
        labels:
          app: mongodb
      spec:
        containers:
        - name: mongodb
          image: mongo
          ports:
          - containerPort: 27017
          env:
          - name: MONGO_INITDB_ROOT_USERNAME
            valueFrom: 
              secretKeyRef:
                name: mongodb-secret
                key: mongodb-root-username
          - name: MONGO_INITDB_ROOT_PASSWORD
            valueFrom:
              secretKeyRef:
                name: mongodb-secret
                key: mogoddb-root-password
# --- these three - (dashes's) indicate file break which means we can add service configuration in same file as deployment configs
---
apiVersion: v1
kind: Service
metadata:
  name: mongodb-service
spec:
  selector:
    name: mongodb
  ports:
  - protocol: TCP
    port: 27017
    targetPort: 27017