Dyn-ingress

Dyn-ingress can solve two Kubernetes common issue:

Add a label containing the node name on each pod.
Create and maintain an Ingress to access your pod directly.

labeling only feature

If you only need to add node name label use this image and use the following env variables:

LABEL.all = 1 force the container to tag all pods
LABEL_NODE_NAME = nodename change the default label name to store the node name (default is nodename)
NAMESPACE = default choose the namespace you will work with

Minimal configuration:

apiVersion: v1
kind: Pod
metadata:
  name: dyn-ingress
spec:
  containers:
  - name: dyn-ingress
    image: urielch/dyn-ingress:latest
    env:
    - name: LABEL.all
      value: "1"
    - name: NAMESPACE
      value: "default"

Enable Ingress

This image had been created to get direct access to all your pods via an Ingress. This is meant to be used with a DemonSet / Deployment or StateFulset.

To activate this feature, you must define this environment variables:

INGRESS.{NAMESPACE}.{IngresName}.host the virtualhost to use, (MUST exist in the piloted Ingress)
INGRESS.{NAMESPACE}.{IngresName}.1.name name of the DemonSet / Deployment or StateFulset you want to access
INGRESS.{NAMESPACE}.{IngresName}.1.selector selector to match your pods like app=MyApp
INGRESS.{NAMESPACE}.{IngresName}.1.prefix Prefix for the new Ingress routes example: /no-lb-service/NODENAME, NODENAME will be replace by the actial nodename
INGRESS.{NAMESPACE}.{IngresName}.1.port Service pod port
INGRESS.{NAMESPACE}.{IngresName}.1.targetPort Service pod targetPort
HTTP_PORT Dyn-ingress pod will listen to this port for his ingress index

To fin the current available routes, dyn-ingress will create two extra entry point route per configuration, the vrevious configuration will add /no-lb-service/ and /no-lb-service that will return a json list of available nodes.

Ingress K3d sample configuration

apiVersion: v1
kind: Pod
metadata:
  name: dyn-ingress
spec:
  containers:
  - name: dyn-ingress
    image: urielch/dyn-ingress:latest
    env:
    - name: HTTP_PORT
      value: "8080"
    - name: INGRESS.default.my-ingress.host
      value: ""
    - name: INGRESS.default.my-ingress.1.name
      value: "my-deployment"
    - name: INGRESS.default.my-ingress.1.selector
      value: "app=my-deployment"
    - name: INGRESS.default.my-ingress.1.prefix
      value: "/stuff/NODENAME"
    - name: INGRESS.default.my-ingress.1.port
      value: "8080"
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: my-ingress
  namespace: default
  annotations:
    kubernetes.io/ingress.class: traefik
    traefik.ingress.kubernetes.io/router.middlewares: default-strip-prefix@kubernetescrd
spec:
  rules:
    - http:
        paths:
          - path: /dummy
            pathType: Prefix
            backend:
              service:
                name: non-existing-service
                port:
                  number: 80

This configuration will add extra route: http://<cluser>/stuff/nodename/url to be redirect to http://<podIP>:80/url

Full sample with RBAC

# Middleware to drop prefix
apiVersion: traefik.containo.us/v1alpha1
kind: Middleware
metadata:
  name: strip-prefix
  annotations:
    kubernetes.io/ingress.class: traefik
spec:
  replacePathRegex:
    regex: ^/(?:[^/]+)/?(.*)
    replacement: /$1
---
# The dynamique ingress with an exact path /list to get all nodes
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: remote-droid-ingress
  namespace: default
  annotations:
    kubernetes.io/ingress.class: traefik
    traefik.ingress.kubernetes.io/router.middlewares: default-strip-prefix@kubernetescrd
spec:
  rules:
    - http:
        paths:
          - path: /list
            pathType: Exact
            backend:
              service:
                name: dyn-ingress-service
                port:
                  number: 8080
---
# Create a service account for dyn-ingress
apiVersion: v1
kind: ServiceAccount
metadata:
  name: dyn-ingress-account
---
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
  namespace: default
  name: dyn-ingress-account
rules:
- apiGroups: [""] # "" indicates the core API group
  resources: ["pods"]
  verbs: ["get", "watch", "list", "patch"]
- apiGroups: [""] # "" indicates the core API group
  resources: ["services"]
  verbs: ["get", "watch", "list", "create", "delete", "update"]
- apiGroups: ["networking.k8s.io"] # "" indicates the core API group
  resources: ["ingresses"]
  verbs: ["get", "watch", "list", "update"]
---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
  name: dyn-ingress-account
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: Role
  name: dyn-ingress-account
subjects:
- kind: ServiceAccount
  name: dyn-ingress-account
---
# Dyn-ingress Deployement, dynamicaly manage ingresses and services
apiVersion: apps/v1
kind: Deployment
metadata:
  name: dyn-ingress
  labels:
    app: dyn-ingress
spec:
  replicas: 1
  selector:
    matchLabels:
      app: dyn-ingress
  template:
    metadata:
      labels:
        app: dyn-ingress
    spec:
      serviceAccountName: dyn-ingress-account
      #tolerations:
      affinity:
        nodeAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
            nodeSelectorTerms:
              - matchExpressions:
                  - key: node-role.kubernetes.io/master
                    operator: In
                    values:
                      - "true"
      containers:
        - name: dyn-ingress
          image: urielch/dyn-ingress:latest
          imagePullPolicy: Always
          resources:
            limits:
              memory: 128Mi
              cpu: "0.2"
          ports:
            - containerPort: 8080
          env:
            - name: HTTP_PORT
              value: "8080"
            - name: INGRESS.default.my-ingress.host
              value: ""
            - name: INGRESS.default.my-ingress.1.name
              value: "my-deployment"
            - name: INGRESS.default.my-ingress.1.selector
              value: "app=my-deployment"
            - name: INGRESS.default.my-ingress.1.prefix
              value: "/stuff/NODENAME"
            - name: INGRESS.default.my-ingress.1.port
              value: "8080"

---
# Service to list nodename having valud pods
apiVersion: v1
kind: Service
metadata:
  name: dyn-ingress-service
spec:
  type: ClusterIP
  selector:
    app: dyn-ingress
  ports:
    - protocol: TCP
      port: 8080
      targetPort: 8080

TODO: