kubernetes ingress ab test

example of how ingress can be used for ab tests

---
apiVersion: v1
kind: ConfigMap
metadata:
  name: nginx-a
data:
  index.html: |
    <style>html,body{display:flex;align-items:center;justify-content:center;font-size:25vh}</style>
    A
---
apiVersion: v1
kind: ConfigMap
metadata:
  name: nginx-b
data:
  index.html: |
    <style>html,body{display:flex;align-items:center;justify-content:center;font-size:25vh}</style>
    B
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-a
  labels:
    app: nginx-a
spec:
  replicas: 1
  strategy:
    rollingUpdate:
      maxSurge: 1
      maxUnavailable: 0
    type: RollingUpdate
  selector:
    matchLabels:
      app: nginx-a
  template:
    metadata:
      labels:
        app: nginx-a
      annotations:
        owner: alexandrm@rabota.ua
        repository: http://hg.nginx.org/nginx/
    spec:
      volumes:
        - name: nginx-a
          configMap:
            name: nginx-a
      containers:
        - name: nginx-a
          image: nginx
          imagePullPolicy: IfNotPresent
          ports:
            - containerPort: 80
          resources:
            limits:
              cpu: 500m
              memory: 500Mi
            requests:
              cpu: 50m
              memory: 100Mi
          readinessProbe:
            failureThreshold: 1
            periodSeconds: 5
            timeoutSeconds: 1
            successThreshold: 1
            tcpSocket:
              port: 80
          livenessProbe:
            failureThreshold: 3
            httpGet:
              path: /
              port: 80
              scheme: HTTP
            periodSeconds: 10
            successThreshold: 1
            timeoutSeconds: 5
          startupProbe:
            failureThreshold: 10
            httpGet:
              path: /
              port: 80
              scheme: HTTP
            periodSeconds: 10
            successThreshold: 1
            timeoutSeconds: 5
          volumeMounts:
            - name: nginx-a
              mountPath: /usr/share/nginx/html
      affinity:
        nodeAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
            nodeSelectorTerms:
              - matchExpressions:
                  - key: poolDestination
                    operator: In
                    values:
                      - app
---
apiVersion: v1
kind: Service
metadata:
  name: nginx-a
  labels:
    app: nginx-a
spec:
  type: ClusterIP
  selector:
    app: nginx-a
  ports:
    - protocol: TCP
      port: 80
      targetPort: 80
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-b
  labels:
    app: nginx-b
spec:
  replicas: 1
  strategy:
    rollingUpdate:
      maxSurge: 1
      maxUnavailable: 0
    type: RollingUpdate
  selector:
    matchLabels:
      app: nginx-b
  template:
    metadata:
      labels:
        app: nginx-b
      annotations:
        owner: alexandrm@rabota.ua
        repository: http://hg.nginx.org/nginx/
    spec:
      volumes:
        - name: nginx-b
          configMap:
            name: nginx-b
      containers:
        - name: nginx-b
          image: nginx
          imagePullPolicy: IfNotPresent
          ports:
            - containerPort: 80
          resources:
            limits:
              cpu: 500m
              memory: 500Mi
            requests:
              cpu: 50m
              memory: 100Mi
          readinessProbe:
            failureThreshold: 1
            periodSeconds: 5
            timeoutSeconds: 1
            successThreshold: 1
            tcpSocket:
              port: 80
          livenessProbe:
            failureThreshold: 3
            httpGet:
              path: /
              port: 80
              scheme: HTTP
            periodSeconds: 10
            successThreshold: 1
            timeoutSeconds: 5
          startupProbe:
            failureThreshold: 10
            httpGet:
              path: /
              port: 80
              scheme: HTTP
            periodSeconds: 10
            successThreshold: 1
            timeoutSeconds: 5
          volumeMounts:
            - name: nginx-b
              mountPath: /usr/share/nginx/html
      affinity:
        nodeAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
            nodeSelectorTerms:
              - matchExpressions:
                  - key: poolDestination
                    operator: In
                    values:
                      - app
---
apiVersion: v1
kind: Service
metadata:
  name: nginx-b
  labels:
    app: nginx-b
spec:
  type: ClusterIP
  selector:
    app: nginx-b
  ports:
    - protocol: TCP
      port: 80
      targetPort: 80
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: nginx-a
  labels:
    app: nginx-a
spec:
  ingressClassName: external
  rules:
    - host: nginx-ab.marchenko1985.github.io
      http:
        paths:
          - backend:
              service:
                name: nginx-a
                port:
                  number: 80
            path: /
            pathType: ImplementationSpecific
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: nginx-b
  labels:
    app: nginx-b
  annotations:
    owner: alexandrm@rabota.ua
    repository: http://hg.nginx.org/nginx/
    # POI: enables traffic split 50%
    nginx.ingress.kubernetes.io/canary: "true"
    nginx.ingress.kubernetes.io/canary-weight: "50"
spec:
  ingressClassName: external
  rules:
    # POI: DNS is same as in previous ingress
    - host: nginx-ab.marchenko1985.github.io
      http:
        paths:
          - backend:
              service:
                name: nginx-b
                port:
                  number: 80
            path: /
            pathType: ImplementationSpecific

the key point here is that we are adding second ingress looking at same domain with following annotations:

nginx.ingress.kubernetes.io/canary: "true"
nginx.ingress.kubernetes.io/canary-weight: "50"

we can test it like so:

curl -s --resolve nginx-ab.dev.rabota.ua:80:20.13.179.68 http://nginx-ab.dev.rabota.ua/ | grep -E "A|B"

original article