apiVersion: apps/v1
kind: Deployment
metadata:
  name: mongo-express
  labels:
    app: mongo-express
    group: db
spec:
  replicas: 1
  selector:
    matchLabels:
      app: mongo-express
  template:
    metadata:
      labels:
        app: mongo-express
        group: db
    spec:
      containers:
        - name: mongo-express
          image: mongo-express:1.0.2
          ports:
            - containerPort: 8081
          env:
            # Both credential pairs come from the one `mongodb-secret` the StatefulSet already
            # consumes: the UI authenticates to mongod with the root credentials, and gates its
            # own session behind the same pair rather than the image's admin/pass defaults.
            - name: ME_CONFIG_MONGODB_ADMINUSERNAME
              valueFrom:
                secretKeyRef:
                  name: mongodb-secret
                  key: username
            - name: ME_CONFIG_MONGODB_ADMINPASSWORD
              valueFrom:
                secretKeyRef:
                  name: mongodb-secret
                  key: password
            - name: ME_CONFIG_BASICAUTH_USERNAME
              valueFrom:
                secretKeyRef:
                  name: mongodb-secret
                  key: username
            - name: ME_CONFIG_BASICAUTH_PASSWORD
              valueFrom:
                secretKeyRef:
                  name: mongodb-secret
                  key: password
            - name: ME_CONFIG_SITE_BASEURL
              value: '/mongo/'
            # In-cluster identity of the first replica, identical under Kind, Kubeadm and K3s.
            # The driver reads the replica set config from it and reaches the remaining members
            # through the same headless service.
            - name: ME_CONFIG_MONGODB_SERVER
              value: 'mongodb-0.mongodb-service'
            - name: ME_CONFIG_MONGODB_PORT
              value: '27017'
            - name: ME_CONFIG_MONGODB_AUTH_DATABASE
              value: 'admin'
            # Without this the UI only lists the databases named in its config; the point of the
            # deployment is browsing whatever collections the StatefulSet actually holds.
            - name: ME_CONFIG_MONGODB_ENABLE_ADMIN
              value: 'true'
          readinessProbe:
            tcpSocket:
              port: 8081
            initialDelaySeconds: 10
            periodSeconds: 10
            timeoutSeconds: 5
          livenessProbe:
            tcpSocket:
              port: 8081
            initialDelaySeconds: 30
            periodSeconds: 20
            timeoutSeconds: 5
          resources:
            requests:
              cpu: '50m'
              memory: '128Mi'
            limits:
              cpu: '500m'
              memory: '256Mi'