Add example using custom headers

examples/README.md

@@ -75,4 +75,8 @@ Name | Description | Platform   | Complexity Level
 -----| ----------- | ---------- | ----------------
 Dummy  | A simple dummy controller that logs updates | * | Advanced
 
+## Custommization
 
+Name | Description | Platform   | Complexity Level
+-----| ----------- | ---------- | ----------------
+custom-headers  | set custom headers before send traffic to backends  | nginx | Advanced

examples/customization/custom-headers/nginx/README.md

@@ -0,0 +1,40 @@
+# Deploying the Nginx Ingress controller
+
+This example aims to demonstrate the deployment of an nginx ingress controller and
+use a ConfigMap to configure a custom list of headers to be passed to the upstream
+server
+
+## Default Backend
+
+The default backend is a Service capable of handling all url paths and hosts the
+nginx controller doesn't understand. This most basic implementation just returns
+a 404 page:
+
+```console
+$ kubectl apply -f default-backend.yaml
+deployment "default-http-backend" created
+service "default-http-backend" created
+
+$ kubectl -n kube-system get po
+NAME                                    READY     STATUS    RESTARTS   AGE
+default-http-backend-2657704409-qgwdd   1/1       Running   0          28s
+```
+
+## Controller
+
+You can deploy the controller as follows:
+
+```console
+$ kubectl apply -f nginx-ingress-controller.yaml
+deployment "nginx-ingress-controller" created
+
+$ kubectl -n kube-system get po
+NAME                                       READY     STATUS    RESTARTS   AGE
+default-http-backend-2657704409-qgwdd      1/1       Running   0          2m
+nginx-ingress-controller-873061567-4n3k2   1/1       Running   0          42s
+```
+
+Note the default settings of this controller:
+* serves a `/healthz` url on port 10254, as both a liveness and readiness probe
+* takes a `--default-backend-service` argument pointing to the Service created above
+

examples/customization/custom-headers/nginx/default-backend.yaml

@@ -0,0 +1,51 @@
+apiVersion: extensions/v1beta1
+kind: Deployment
+metadata:
+  name: default-http-backend
+  labels:
+    k8s-app: default-http-backend
+  namespace: kube-system
+spec:
+  replicas: 1
+  template:
+    metadata:
+      labels:
+        k8s-app: default-http-backend
+    spec:
+      terminationGracePeriodSeconds: 60
+      containers:
+      - name: default-http-backend
+        # Any image is permissable as long as:
+        # 1. It serves a 404 page at /
+        # 2. It serves 200 on a /healthz endpoint
+        image: gcr.io/google_containers/defaultbackend:1.0
+        livenessProbe:
+          httpGet:
+            path: /healthz
+            port: 8080
+            scheme: HTTP
+          initialDelaySeconds: 30
+          timeoutSeconds: 5
+        ports:
+        - containerPort: 8080
+        resources:
+          limits:
+            cpu: 10m
+            memory: 20Mi
+          requests:
+            cpu: 10m
+            memory: 20Mi
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: default-http-backend
+  namespace: kube-system
+  labels:
+    k8s-app: default-http-backend
+spec:
+  ports:
+  - port: 80
+    targetPort: 8080
+  selector:
+    k8s-app: default-http-backend

examples/customization/custom-headers/nginx/nginx-ingress-controller.yaml

@@ -0,0 +1,52 @@
+apiVersion: extensions/v1beta1
+kind: Deployment
+metadata:
+  name: nginx-ingress-controller
+  labels:
+    k8s-app: nginx-ingress-controller
+  namespace: kube-system
+spec:
+  replicas: 1
+  template:
+    metadata:
+      labels:
+        k8s-app: nginx-ingress-controller
+    spec:
+      # hostNetwork makes it possible to use ipv6 and to preserve the source IP correctly regardless of docker configuration
+      # however, it is not a hard dependency of the nginx-ingress-controller itself and it may cause issues if port 10254 already is taken on the host
+      # that said, since hostPort is broken on CNI (https://github.com/kubernetes/kubernetes/issues/31307) we have to use hostNetwork where CNI is used
+      # like with kubeadm
+      # hostNetwork: true
+      terminationGracePeriodSeconds: 60
+      containers:
+      - image: gcr.io/google_containers/nginx-ingress-controller:0.9.0-beta.1
+        name: nginx-ingress-controller
+        readinessProbe:
+          httpGet:
+            path: /healthz
+            port: 10254
+            scheme: HTTP
+        livenessProbe:
+          httpGet:
+            path: /healthz
+            port: 10254
+            scheme: HTTP
+          initialDelaySeconds: 10
+          timeoutSeconds: 1
+        ports:
+        - containerPort: 80
+          hostPort: 80
+        - containerPort: 443
+          hostPort: 443
+        env:
+          - name: POD_NAME
+            valueFrom:
+              fieldRef:
+                fieldPath: metadata.name
+          - name: POD_NAMESPACE
+            valueFrom:
+              fieldRef:
+                fieldPath: metadata.namespace
+        args:
+        - /nginx-ingress-controller
+        - --default-backend-service=$(POD_NAMESPACE)/default-http-backend