Merge pull request #41804 from chakri-nelluri/flex

Automatic merge from submit-queue (batch tested with PRs 41116, 41804, 42104, 42111, 42120)

Add support for attacher/detacher interface in Flex volume

Add support for attacher/detacher interface in Flex volume
This change breaks backward compatibility and requires to be release noted.

```release-note
Flex volume plugin is updated to support attach/detach interfaces. It broke backward compatibility. Please update your drivers and implement the new callouts. 
```

volumes/flexvolume/lvm

@@ -19,10 +19,13 @@
 usage() {
 	err "Invalid usage. Usage: "
 	err "\t$0 init"
-	err "\t$0 attach <json params>"
+	err "\t$0 attach <json params> <nodename>"
-	err "\t$0 detach <mount device>"
+	err "\t$0 detach <mount device> <nodename>"
-	err "\t$0 mount <mount dir> <mount device> <json params>"
+	err "\t$0 waitforattach <mount device> <json params>"
-	err "\t$0 unmount <mount dir>"
+	err "\t$0 mountdevice <mount dir> <mount device> <json params>"
+	err "\t$0 unmountdevice <mount dir>"
+	err "\t$0 getvolumename <json params>"
+	err "\t$0 isattached <json params> <nodename>"
 	exit 1
 }
 
@@ -43,16 +46,23 @@ ismounted() {
 	fi
 }
 
-attach() {
+getdevice() {
-	VOLUMEID=$(echo $1 | jq -r '.volumeID')
+	VOLUMEID=$(echo ${JSON_PARAMS} | jq -r '.volumeID')
-	SIZE=$(echo $1 | jq -r '.size')
+	VG=$(echo ${JSON_PARAMS}|jq -r '.volumegroup')
-	VG=$(echo $1|jq -r '.volumegroup')
 
 	# LVM substitutes - with --
 	VOLUMEID=`echo $VOLUMEID|sed s/-/--/g`
 	VG=`echo $VG|sed s/-/--/g`
 
 	DMDEV="/dev/mapper/${VG}-${VOLUMEID}"
+	echo ${DMDEV}
+}
+
+attach() {
+	JSON_PARAMS=$1
+	SIZE=$(echo $1 | jq -r '.size')
+
+	DMDEV=$(getdevice)
 	if [ ! -b "${DMDEV}" ]; then
 		err "{\"status\": \"Failure\", \"message\": \"Volume ${VOLUMEID} does not exist\"}"
 		exit 1
@@ -66,7 +76,12 @@ detach() {
 	exit 0
 }
 
-domount() {
+waitforattach() {
+	shift
+	attach $*
+}
+
+domountdevice() {
 	MNTPATH=$1
 	DMDEV=$2
 	FSTYPE=$(echo $3|jq -r '.["kubernetes.io/fsType"]')
@@ -101,8 +116,13 @@ domount() {
 	exit 0
 }
 
-unmount() {
+unmountdevice() {
 	MNTPATH=$1
+	if [ ! -d ${MNTPATH} ]; then
+		log "{\"status\": \"Success\"}"
+		exit 0
+	fi
+
 	if [ $(ismounted) -eq 0 ] ; then
 		log "{\"status\": \"Success\"}"
 		exit 0
@@ -113,12 +133,27 @@ unmount() {
 		err "{ \"status\": \"Failed\", \"message\": \"Failed to unmount volume at ${MNTPATH}\"}"
 		exit 1
 	fi
-	rmdir ${MNTPATH} &> /dev/null
 
 	log "{\"status\": \"Success\"}"
 	exit 0
 }
 
+getvolumename() {
+	JSON_PARAMS=$1
+	DMDEV=$(getdevice)
+
+	# get lvm device UUID
+	UUID=`lvs -o lv_uuid --noheadings ${DMDEV} 2>/dev/null|tr -d " "`
+
+	log "{\"status\": \"Success\", \"volumeName\":\"${UUID}\"}"
+	exit 0
+}
+
+isattached() {
+	log "{\"status\": \"Success\", \"attached\":true}"
+	exit 0
+}
+
 op=$1
 
 if [ "$op" = "init" ]; then
@@ -139,14 +174,24 @@ case "$op" in
 	detach)
 		detach $*
 		;;
-	mount)
+	waitforattach)
-		domount $*
+		waitforattach $*
 		;;
-	unmount)
+	mountdevice)
-		unmount $*
+		domountdevice $*
 		;;
+	unmountdevice)
+		unmountdevice $*
+		;;
+	getvolumename)
+		getvolumename $*
+		;;
+	isattached)
+                isattached $*
+                ;;
 	*)
-		usage
+		err "{ \"status\": \"Not supported\" }"
+		exit 1
 esac
 
 exit 1

volumes/flexvolume/nfs

@@ -0,0 +1,120 @@
+#!/bin/bash
+
+# Copyright 2015 The Kubernetes Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Notes:
+#  - Please install "jq" package before using this driver.
+usage() {
+	err "Invalid usage. Usage: "
+	err "\t$0 init"
+	err "\t$0 mount <mount dir> <json params>"
+	err "\t$0 unmount <mount dir>"
+	err "\t$0 getvolumename <json params>"
+	exit 1
+}
+
+err() {
+	echo -ne $* 1>&2
+}
+
+log() {
+	echo -ne $* >&1
+}
+
+ismounted() {
+	MOUNT=`findmnt -n ${MNTPATH} 2>/dev/null | cut -d' ' -f1`
+	if [ "${MOUNT}" == "${MNTPATH}" ]; then
+		echo "1"
+	else
+		echo "0"
+	fi
+}
+
+domount() {
+	MNTPATH=$1
+
+	NFS_SERVER=$(echo $2 | jq -r '.server')
+	SHARE=$(echo $2 | jq -r '.share')
+
+	if [ $(ismounted) -eq 1 ] ; then
+		log "{\"status\": \"Success\"}"
+		exit 0
+	fi
+
+	mkdir -p ${MNTPATH} &> /dev/null
+
+	mount -t nfs ${NFS_SERVER}:/${SHARE} ${MNTPATH} &> /dev/null
+	if [ $? -ne 0 ]; then
+		err "{ \"status\": \"Failure\", \"message\": \"Failed to mount ${NFS_SERVER}:${SHARE} at ${MNTPATH}\"}"
+		exit 1
+	fi
+	log "{\"status\": \"Success\"}"
+	exit 0
+}
+
+unmount() {
+	MNTPATH=$1
+	if [ $(ismounted) -eq 0 ] ; then
+		log "{\"status\": \"Success\"}"
+		exit 0
+	fi
+
+	umount ${MNTPATH} &> /dev/null
+	if [ $? -ne 0 ]; then
+		err "{ \"status\": \"Failed\", \"message\": \"Failed to unmount volume at ${MNTPATH}\"}"
+		exit 1
+	fi
+
+	log "{\"status\": \"Success\"}"
+	exit 0
+}
+
+getvolumename() {
+	NFS_SERVER=$(echo $1 | jq -r '.server')
+	SHARE=$(echo $1 | jq -r '.share')
+
+	log "{\"status\": \"Success\", \"volumeName\": \"${NFS_SERVER}/${SHARE}\"}"
+	exit 0
+}
+
+op=$1
+
+if [ "$op" = "init" ]; then
+	log "{\"status\": \"Success\"}"
+	exit 0
+fi
+
+if [ $# -lt 2 ]; then
+	usage
+fi
+
+shift
+
+case "$op" in
+	mount)
+		domount $*
+		;;
+	unmount)
+		unmount $*
+		;;
+	getvolumename)
+		getvolumename $*
+		;;
+	*)
+		err "{ \"status\": \"Not supported\" }"
+		exit 1
+esac
+
+exit 1

volumes/flexvolume/nginx-nfs.yaml

@@ -0,0 +1,22 @@
+apiVersion: v1
+kind: Pod
+metadata:
+  name: nginx-nfs
+  namespace: default
+spec:
+  containers:
+  - name: nginx-nfs
+    image: nginx
+    volumeMounts:
+    - name: test
+      mountPath: /data
+    ports:
+    - containerPort: 80
+  volumes:
+  - name: test
+    flexVolume:
+      driver: "k8s/nfs"
+      fsType: "nfs"
+      options:
+        server: "172.16.0.25"
+        share: "dws_nas_scratch"

volumes/flexvolume/nginx.yaml

@@ -2,6 +2,7 @@ apiVersion: v1
 kind: Pod
 metadata:
   name: nginx
+  namespace: default
 spec:
   containers:
   - name: nginx
@@ -20,4 +21,3 @@ spec:
         volumeID: "vol1"
         size: "1000m"
         volumegroup: "kube_vg"
-