Updated node/pod HOSTNAME, HOST and IDENTITY and ADDRESS env variable…

… with Kubernetes pod name from metadata name

This StatefulSet of Apache NiFi deployment uses hostname as reference in the cluster names. When Apache NiFi nodes/pods occasionally terminated and redeployed old zombie nodes/pods hostnames are still list in the cluster page and can not be removed, this will/should fix that bug

The HOSTNAME env variable is never empty as Kubernetes controller will always populate it if is not set

deployment/nifi.yml

@@ -77,23 +77,23 @@ spec:
           - name: NIFI_WEB_HTTP_HOST
             valueFrom:
               fieldRef:
-                fieldPath: status.podIP
+                fieldPath: metadata.name # Use pod name as web host
           - name: NIFI_CLUSTER_NODE_ADDRESS
             valueFrom:
               fieldRef:
-                fieldPath: status.podIP
+                fieldPath: metadata.name # Use pod name as node address
           - name: NIFI_REMOTE_INPUT_HOST
             valueFrom:
               fieldRef:
-                fieldPath: status.podIP
+                fieldPath: metadata.name # Use pod name as input host
           - name: HOSTNAME
             valueFrom:
               fieldRef:
-                fieldPath: status.podIP
+                fieldPath: metadata.name # Use pod name as hostname
           - name: NODE_IDENTITY
             valueFrom:
               fieldRef:
-                fieldPath: metadata.name
+                fieldPath: metadata.name # Use pod name as identity
         envFrom:
           - configMapRef:
               name: nifi-cm