Add example of custom error pages in nginx ingress controller

controllers/nginx/README.md

@@ -208,7 +208,7 @@ In case of an error in a request the body of the response is obtained from the `
 - `X-Code` indicates the HTTP code
 - `X-Format` the value of the `Accept` header
 
-Using this two headers is possible to use a custom backend service like [this one](https://github.com/aledbf/contrib/tree/nginx-debug-server/Ingress/images/nginx-error-server) that inspect each request and returns a custom error page with the format expected by the client. This images handles `html` and `json` responses.
+Using this two headers is possible to use a custom backend service like [this one](https://github.com/aledbf/contrib/tree/nginx-debug-server/Ingress/images/nginx-error-server) that inspect each request and returns a custom error page with the format expected by the client. Please check the example [custom-errors](examples/custom-errors/README.md)
 
 
 ## Troubleshooting

controllers/nginx/examples/custom-errors/README.md

@@ -0,0 +1,80 @@
+
+This example shows how is possible to use a custom backend to render custom error pages. The code of this example is located here [nginx-debug-server](https://github.com/aledbf/contrib/tree/nginx-debug-server)
+
+
+The idea is to use the headers `X-Code` and `X-Format` that NGINX pass to the backend in case of an error to find out the best existent representation of the response to be returned. i.e. if the request contains an `Accept` header of type `json` the error should be in that format and not in `html` (the default in NGINX).
+
+First create the custom backend to use in the Ingress controller
+
+```$ kubectl create -f custom-default-backend.yaml
+service "nginx-errors" created
+replicationcontroller "nginx-errors" created
+```
+
+```$ kubectl get svc
+NAME                    CLUSTER-IP   EXTERNAL-IP   PORT(S)         AGE
+echoheaders             10.3.0.7     nodes         80/TCP          23d
+kubernetes              10.3.0.1     <none>        443/TCP         34d
+nginx-errors            10.3.0.102   <none>        80/TCP          11s
+```
+
+```$ kubectl get rc
+CONTROLLER             REPLICAS   AGE
+echoheaders            1          19d
+nginx-errors           1          19s
+```
+
+Next create the Ingress controller executing
+```
+$ kubectl create -f rc-custom-errors.yaml
+```
+
+Now to check if this is working we use curl:
+
+```
+$ curl -v http://172.17.4.99/
+*   Trying 172.17.4.99...
+* Connected to 172.17.4.99 (172.17.4.99) port 80 (#0)
+> GET / HTTP/1.1
+> Host: 172.17.4.99
+> User-Agent: curl/7.43.0
+> Accept: */*
+>
+< HTTP/1.1 404 Not Found
+< Server: nginx/1.10.0
+< Date: Wed, 04 May 2016 02:53:45 GMT
+< Content-Type: text/html
+< Transfer-Encoding: chunked
+< Connection: keep-alive
+< Vary: Accept-Encoding
+<
+<span>The page you're looking for could not be found.</span>
+
+* Connection #0 to host 172.17.4.99 left intact
+```
+
+Specifying json as expected format:
+
+```
+$ curl -v http://172.17.4.99/ -H 'Accept: application/json'
+*   Trying 172.17.4.99...
+* Connected to 172.17.4.99 (172.17.4.99) port 80 (#0)
+> GET / HTTP/1.1
+> Host: 172.17.4.99
+> User-Agent: curl/7.43.0
+> Accept: application/json
+>
+< HTTP/1.1 404 Not Found
+< Server: nginx/1.10.0
+< Date: Wed, 04 May 2016 02:54:00 GMT
+< Content-Type: text/html
+< Transfer-Encoding: chunked
+< Connection: keep-alive
+< Vary: Accept-Encoding
+<
+{ "message": "The page you're looking for could not be found" }
+
+* Connection #0 to host 172.17.4.99 left intact
+```
+
+By default the Ingress controller provides support for `html`, `json` and `XML`.

controllers/nginx/examples/custom-errors/custom-default-backend.yaml

@@ -0,0 +1,31 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: nginx-errors
+  labels:
+    app: nginx-errors
+spec:
+  ports:
+  - port: 80
+    targetPort: 80
+    protocol: TCP
+    name: http
+  selector:
+    app: nginx-errors
+---
+apiVersion: v1
+kind: ReplicationController
+metadata:
+  name: nginx-errors
+spec:
+  replicas: 1
+  template:
+    metadata:
+      labels:
+        app: nginx-errors
+    spec:
+      containers:
+      - name: nginx-errors
+        image: aledbf/nginx-error-server:0.1
+        ports:
+        - containerPort: 80

controllers/nginx/examples/custom-errors/rc-custom-errors.yaml

@@ -0,0 +1,46 @@
+apiVersion: v1
+kind: ReplicationController
+metadata:
+  name: nginx-ingress-controller
+  labels:
+    k8s-app: nginx-ingress-lb
+spec:
+  replicas: 1
+  selector:
+    k8s-app: nginx-ingress-lb
+  template:
+    metadata:
+      labels:
+        k8s-app: nginx-ingress-lb
+        name: nginx-ingress-lb
+    spec:
+      terminationGracePeriodSeconds: 60      
+      containers:
+      - image: gcr.io/google_containers/nginx-ingress-controller:0.6
+        name: nginx-ingress-lb
+        imagePullPolicy: Always
+        livenessProbe:
+          httpGet:
+            path: /healthz
+            port: 10249
+            scheme: HTTP
+          initialDelaySeconds: 30
+          timeoutSeconds: 5
+        # use downward API
+        env:
+          - name: POD_NAME
+            valueFrom:
+              fieldRef:
+                fieldPath: metadata.name
+          - name: POD_NAMESPACE
+            valueFrom:
+              fieldRef:
+                fieldPath: metadata.namespace
+        ports:
+        - containerPort: 80
+          hostPort: 80
+        - containerPort: 443
+          hostPort: 443
+        args:
+        - /nginx-ingress-controller
+        - --default-backend-service=default/nginx-errors