Merge pull request #41 from Yolean/multizone-rack-awareness

Multizone rack awareness

Author: solsson

10broker-config.yml

@@ -11,6 +11,19 @@ data:
     export KAFKA_BROKER_ID=${HOSTNAME##*-}
     sed -i "s/\${KAFKA_BROKER_ID}/$KAFKA_BROKER_ID/" /etc/kafka/server.properties
 
+    hash kubectl 2>/dev/null || {
+      sed -i "s/#init#broker.rack=#init#/#init#broker.rack=# kubectl not found in path/" /etc/kafka/server.properties
+    } && {
+      ZONE=$(kubectl get node "$NODE_NAME" -o=go-template='{{index .metadata.labels "failure-domain.beta.kubernetes.io/zone"}}')
+      if [ $? -ne 0 ]; then
+        sed -i "s/#init#broker.rack=#init#/#init#broker.rack=# zone lookup failed, see -c init-config logs/" /etc/kafka/server.properties
+      elif [ "x$ZONE" == "x<no value>" ]; then
+        sed -i "s/#init#broker.rack=#init#/#init#broker.rack=# zone label not found for node $NODE_NAME/" /etc/kafka/server.properties
+      else
+        sed -i "s/#init#broker.rack=#init#/broker.rack=$ZONE/" /etc/kafka/server.properties
+      fi
+    }
+
   server.properties: |-
     # Licensed to the Apache Software Foundation (ASF) under one or more
     # contributor license agreements.  See the NOTICE file distributed with
@@ -34,6 +47,8 @@ data:
     # The id of the broker. This must be set to a unique integer for each broker.
     broker.id=${KAFKA_BROKER_ID}
 
+    #init#broker.rack=#init#
+
     # Switch to enable topic deletion or not, default value is false
     delete.topic.enable=true
 

50kafka.yml

@@ -15,7 +15,12 @@ spec:
       terminationGracePeriodSeconds: 30
       initContainers:
       - name: init-config
-        image: solsson/kafka:0.11.0.0@sha256:b27560de08d30ebf96d12e74f80afcaca503ad4ca3103e63b1fd43a2e4c976ce
+        image: solsson/kafka-initutils@sha256:c275d681019a0d8f01295dbd4a5bae3cfa945c8d0f7f685ae1f00f2579f08c7d
+        env:
+        - name: NODE_NAME
+          valueFrom:
+            fieldRef:
+              fieldPath: spec.nodeName
         command: ['/bin/bash', '/etc/kafka/init.sh']
         volumeMounts:
         - name: config

rbac-namespace-default/node-reader.yml

@@ -0,0 +1,37 @@
+# To see if init containers need RBAC:
+#
+# $ kubectl exec kafka-0 -- cat /etc/kafka/server.properties | grep broker.rack
+# #init#broker.rack=# zone lookup failed, see -c init-config logs
+# $ kubectl logs -c init-config kafka-0
+# ++ kubectl get node some-node '-o=go-template={{index .metadata.labels "failure-domain.beta.kubernetes.io/zone"}}'
+# Error from server (Forbidden): User "system:serviceaccount:kafka:default" cannot get nodes at the cluster scope.: "Unknown user \"system:serviceaccount:kafka:default\""
+#
+---
+kind: ClusterRole
+apiVersion: rbac.authorization.k8s.io/v1beta1
+metadata:
+  name: node-reader
+  labels:
+    origin: github.com_Yolean_kubernetes-kafka
+rules:
+- apiGroups:
+  - ""
+  resources:
+  - nodes
+  verbs:
+  - get
+---
+kind: ClusterRoleBinding
+apiVersion: rbac.authorization.k8s.io/v1beta1
+metadata:
+  name: kafka-node-reader
+  labels:
+    origin: github.com_Yolean_kubernetes-kafka
+roleRef:
+  apiGroup: rbac.authorization.k8s.io
+  kind: ClusterRole
+  name: node-reader
+subjects:
+- kind: ServiceAccount
+  name: default
+  namespace: kafka