Single K8S Node Of Deploying SDNC Cluster POC

It's a reference of how to deploy sdnc cluster under
single node k8s environment.

Currently the config of nfs for mysql db only
supports one k8s node. For mutiple nodes, because
of dockernfs mount, nfs provisioner has conflict with
it, which fails mount operation of SDNC pod.

Also, if SDNC needs to fully utilize mysql cluster under
k8s, in core project, DbLibService.java should be enhanced
to support that writing to master only and reading from them.

Issue-ID: SDNC-163
Change-Id: I85ad327f2fe04fe8e9a135289d7c25a917234438
Signed-off-by: Hao Kuang <Hao.Kuang@amdocs.com>
diff --git a/kubernetes/sdnc/templates/db-statefulset.yaml b/kubernetes/sdnc/templates/db-statefulset.yaml
new file mode 100644
index 0000000..f2e079d
--- /dev/null
+++ b/kubernetes/sdnc/templates/db-statefulset.yaml
@@ -0,0 +1,193 @@
+#{{ if not .Values.disableSdncSdncDbhost }}
+apiVersion: apps/v1beta1
+kind: StatefulSet
+metadata:
+  name: sdnc-dbhost
+  namespace: "{{ .Values.nsPrefix }}-sdnc"
+spec:
+  serviceName: "dbhost"
+  replicas: {{ .Values.numberOfDbReplicas }}
+  selector:
+    matchLabels:
+      app: sdnc-dbhost
+  template:
+    metadata:
+      labels:
+        app: sdnc-dbhost
+      name: sdnc-dbhost
+    spec:
+      initContainers:
+      - name: init-mysql
+        image: {{ .Values.image.mysql }}
+        imagePullPolicy: {{ .Values.pullPolicy }}
+        command:
+        - bash
+        - "-c"
+        - |
+          set -ex
+          # Generate mysql server-id from pod ordinal index.
+          [[ `hostname` =~ -([0-9]+)$ ]] || exit 1
+          ordinal=${BASH_REMATCH[1]}
+          echo BASH_REMATCH=${BASH_REMATCH}
+          echo [mysqld] > /mnt/conf.d/server-id.cnf
+          # Add an offset to avoid reserved server-id=0 value.
+          echo server-id=$((100 + $ordinal)) >> /mnt/conf.d/server-id.cnf
+          # Copy appropriate conf.d files from config-map to emptyDir.
+          if [[ $ordinal -eq 0 ]]; then
+            cp /mnt/config-map/master.cnf /mnt/conf.d/
+          else
+            cp /mnt/config-map/slave.cnf /mnt/conf.d/
+          fi
+        volumeMounts:
+        - name: conf
+          mountPath: /mnt/conf.d
+        - name: config-map
+          mountPath: /mnt/config-map
+      - name: clone-mysql
+        image: {{ .Values.image.xtrabackup }}
+        env:
+        - name: MYSQL_ROOT_PASSWORD
+          value: openECOMP1.0
+        command:
+        - bash
+        - "-c"
+        - |
+          set -ex
+          # Skip the clone if data already exists.
+          [[ -d /var/lib/mysql/mysql ]] && exit 0
+          # Skip the clone on master (ordinal index 0).
+          [[ `hostname` =~ -([0-9]+)$ ]] || exit 1
+          ordinal=${BASH_REMATCH[1]}
+          echo ${BASH_REMATCH}
+          [[ $ordinal -eq 0 ]] && exit 0
+          # Clone data from previous peer.
+          ncat --recv-only sdnc-dbhost-$(($ordinal-1)).dbhost.{{ .Values.nsPrefix }}-sdnc 3307 | xbstream -x -C /var/lib/mysql
+          # Prepare the backup.
+          xtrabackup --user=root --password=$MYSQL_ROOT_PASSWORD --prepare --target-dir=/var/lib/mysql
+          ls -l /var/lib/mysql
+        volumeMounts:
+        - name: sdnc-data
+          mountPath: /var/lib/mysql
+          subPath: mysql
+        - name: conf
+          mountPath: /etc/mysql/conf.d
+      containers:
+      - env:
+        - name: MYSQL_ROOT_PASSWORD
+          value: openECOMP1.0
+        - name: MYSQL_ROOT_HOST
+          value: '%'
+        - name: MYSQL_ALLOW_EMPTY_PASSWORD
+          value: "0"
+        image: {{ .Values.image.mysql }}
+        imagePullPolicy: {{ .Values.pullPolicy }}
+        name: sdnc-db-container
+        volumeMounts:
+        - mountPath: /var/lib/mysql
+          name: sdnc-data
+          subPath: mysql
+        - name: conf
+          mountPath: /etc/mysql/conf.d
+        ports:
+        - containerPort: 3306
+        resources:
+          requests:
+            cpu: 500m
+            memory: 1Gi
+        livenessProbe:
+          exec:
+            command: ["mysqladmin", "ping"]
+          initialDelaySeconds: 30
+          periodSeconds: 10
+          timeoutSeconds: 5
+        readinessProbe:
+          tcpSocket:
+            port: 3306
+          initialDelaySeconds: 5
+          periodSeconds: 10
+      - name: xtrabackup
+        image: {{ .Values.image.xtrabackup }}
+        env:
+        - name: MYSQL_ROOT_PASSWORD
+          value: openECOMP1.0
+        ports:
+        - name: xtrabackup
+          containerPort: 3307
+        command:
+        - bash
+        - "-c"
+        - |
+          set -ex
+          cd /var/lib/mysql
+          ls -l
+          # Determine binlog position of cloned data, if any.
+          if [[ -f xtrabackup_slave_info ]]; then
+            echo "Inside xtrabackup_slave_info"
+            # XtraBackup already generated a partial "CHANGE MASTER TO" query
+            # because we're cloning from an existing slave.
+            mv xtrabackup_slave_info change_master_to.sql.in
+            # Ignore xtrabackup_binlog_info in this case (it's useless).
+            rm -f xtrabackup_binlog_info
+          elif [[ -f xtrabackup_binlog_info ]]; then
+            echo "Inside xtrabackup_binlog_info"
+            # We're cloning directly from master. Parse binlog position.
+            [[ `cat xtrabackup_binlog_info` =~ ^(.*?)[[:space:]]+(.*?)$ ]] || exit 1
+            rm xtrabackup_binlog_info
+            echo "CHANGE MASTER TO MASTER_LOG_FILE='${BASH_REMATCH[1]}',\
+                  MASTER_LOG_POS=${BASH_REMATCH[2]}" > change_master_to.sql.in
+          fi
+
+          # Check if we need to complete a clone by starting replication.
+          if [[ -f change_master_to.sql.in ]]; then
+            echo "Waiting for mysqld to be ready (accepting connections)"
+            [[ `hostname` =~ -([0-9]+)$ ]] || exit 1
+            ordinal=${BASH_REMATCH[1]}
+            echo $ordinal
+            until mysql --user=root --password=$MYSQL_ROOT_PASSWORD -h 127.0.0.1 -e "SELECT 1"; do sleep 1; done
+
+            echo "Initializing replication from clone position"
+            # In case of container restart, attempt this at-most-once.
+            mv change_master_to.sql.in change_master_to.sql.orig
+            mysql --user=root --password=$MYSQL_ROOT_PASSWORD -h 127.0.0.1 <<EOF
+          $(<change_master_to.sql.orig),
+            MASTER_HOST="sdnc-dbhost-0.dbhost.{{ .Values.nsPrefix }}-sdnc",
+            MASTER_USER="root",
+            MASTER_PASSWORD="$MYSQL_ROOT_PASSWORD",
+            MASTER_CONNECT_RETRY=10;
+          START SLAVE;
+          EOF
+          fi
+
+          # Start a server to send backups when requested by peers.
+          exec ncat --listen --keep-open --send-only --max-conns=1 3307 -c \
+            "xtrabackup --user=root --password=$MYSQL_ROOT_PASSWORD --backup --slave-info --stream=xbstream --host=127.0.0.1"
+        volumeMounts:
+        - name: sdnc-data
+          mountPath: /var/lib/mysql
+          subPath: mysql
+        - name: conf
+          mountPath: /etc/mysql/conf.d
+        resources:
+          requests:
+            cpu: 100m
+            memory: 100Mi
+      volumes:
+      - name: conf
+        emptyDir: {}
+      - name: config-map
+        configMap:
+          name: mysql
+      - name: localtime
+        hostPath:
+          path: /etc/localtime
+  volumeClaimTemplates:
+  - metadata:
+      name: sdnc-data
+      annotations:
+        volume.beta.kubernetes.io/storage-class: "{{ .Values.nsPrefix }}-sdnc-data"
+    spec:
+      accessModes: ["ReadWriteMany"]
+      resources:
+        requests:
+          storage: 1Gi
+#{{ end }}