create subdirs for volumes

Author: karolmajek

Makefile

@@ -1,6 +1,6 @@
 all: deps compile
 
-VERSION=0.1.0
+VERSION=0.2.0
 
 compile:
 	go build
@@ -38,7 +38,7 @@ deb: compile
 	install -m 0644 docker-volume-moosefs.service obj/debian/lib/systemd/system
 	fpm -C obj/debian --vendor MooseFS -m "contact@moosefs.com" -f \
 			-s dir -t deb -n docker-volume-moosefs \
-			--after-install files/post-install-systemd --version ${VERSION} . && \
+			--version ${VERSION} . && \
 			rm -fr obj/debian
 
 clean:

README.md

@@ -4,6 +4,11 @@ Plugin for MooseFS to create persistent volumes in Docker containers.
 
 <img align="right" alt="MooseFS logo" src="https://moosefs.com/Content/Images/moosefs.png" />
 
+## Version history:
+
+- 0.2.0 Creates new subdirectory for each volume in root e.g. /mnt/moosefs
+- 0.1.0 Mountpoint /mnt/moosefs is used as the volume
+
 ## Preconditions
 
 - **MooseFS** Storage Cluster has to be setup and running
@@ -69,10 +74,12 @@ make rpm
 Assuming we have **MooseFS** mounted in `/mnt/moosefs` we will create a volume labeled `mymoosefs`:
 
 ```
-docker volume create -d moosefs --name mymoosefs -o mountpoint=/mnt/moosefs
+docker volume create -d moosefs --name mymoosefs -o root=/mnt/moosefs
 ```
 
-Without specified mountpoint plugin will assume mounting in `/mnt/$NAME`, so **mymoosefs** should be mounted in `/mnt/myfs` to use short command `docker volume create -d moosefs --name mymoosefs`
+Without specified mountpoint plugin will assume mounting in `/mnt/moosefs/$NAME`, so **mymoosefs** will be mounted in `/mnt/moosefs/mymoosefs`
+
+We can use shorter command: `docker volume create -d moosefs --name mymoosefs`
 
 We can inspect created volume with following command:
 

driver.go

@@ -3,6 +3,7 @@ package main
 import (
 	"errors"
 	"fmt"
+    "os"
 	"path"
 	"path/filepath"
 	"sync"
@@ -16,16 +17,17 @@ import (
 
 // A single volume instance
 type moosefsMount struct {
-	name       string
-	mountpoint string
+	name    string
+    path    string
+	root    string
 }
 
 type moosefsDriver struct {
 	mounts map[string]*moosefsMount
 	m      *sync.Mutex
 }
 
-func newMooseFSDriver(mountpoint string) moosefsDriver {
+func newMooseFSDriver(root string) moosefsDriver {
 	d := moosefsDriver{
 		mounts: make(map[string]*moosefsMount),
 		m:      &sync.Mutex{},
@@ -34,33 +36,43 @@ func newMooseFSDriver(mountpoint string) moosefsDriver {
 }
 
 func (d moosefsDriver) Create(r *volume.CreateRequest) error {
-	var volumeMountpoint string
+    var volumeRoot string
 
 	d.m.Lock()
 	defer d.m.Unlock()
 
-	if optsMountpoint, ok := r.Options["mountpoint"]; ok {
-		volumeMountpoint = optsMountpoint
+	if optsRoot, ok := r.Options["root"]; ok {
+		volumeRoot = optsRoot
 	} else {
-		// Assume the default mountpoint
-		volumeMountpoint = filepath.Join(*mountpoint, r.Name)
+		// Assume the default root
+        volumeRoot = *root
 	}
 
-	if !ismoosefs(volumeMountpoint) {
-		emsg := fmt.Sprintf("Cannot create volume %s as it's not a valid MooseFS mount", volumeMountpoint)
+    volumePath := filepath.Join(volumeRoot, r.Name)
+
+    if err := mkdir(volumePath); err != nil {
+		return err
+	}
+    
+	if !ismoosefs(volumePath) {
+		emsg := fmt.Sprintf("Cannot create volume %s as it's not a valid MooseFS mount", volumePath)
 		log.Error(emsg)
 		return errors.New(emsg)
 	}
 
 	if _, ok := d.mounts[r.Name]; ok {
-		emsg := fmt.Sprintf("Cannot create volume %s, it already exists", volumeMountpoint)
+		emsg := fmt.Sprintf("Cannot create volume %s, it already exists", volumePath)
 		log.Error(emsg)
 		return errors.New(emsg)
 	}
 
+    if err := mkdir(volumePath); err != nil {
+		return err
+	}
 	d.mounts[r.Name] = &moosefsMount{
-		name:       r.Name,
-		mountpoint: volumeMountpoint,
+		name:   r.Name,
+        path:   volumePath,
+		root:   volumeRoot,
 	}
 
 	if *verbose {
@@ -81,20 +93,20 @@ func (d moosefsDriver) Remove(r *volume.RemoveRequest) error {
 
 func (d moosefsDriver) Path(r *volume.PathRequest) (*volume.PathResponse, error) {
 	if _, ok := d.mounts[r.Name]; ok {
-		return &volume.PathResponse{Mountpoint: d.mounts[r.Name].mountpoint}, nil
+		return &volume.PathResponse{Mountpoint: d.mounts[r.Name].path}, nil
 	}
 	return &volume.PathResponse{}, nil
 }
 
 func (d moosefsDriver) Mount(r *volume.MountRequest) (*volume.MountResponse, error) {
-	volumeMountpoint := d.mounts[r.Name].mountpoint
-	if !ismoosefs(volumeMountpoint) {
-		emsg := fmt.Sprintf("Cannot mount volume %s as it's not a valid MooseFS mount", volumeMountpoint)
+	volumePath := filepath.Join(d.mounts[r.Name].root, r.Name)
+	if !ismoosefs(volumePath) {
+		emsg := fmt.Sprintf("Cannot mount volume %s as it's not a valid MooseFS mount", volumePath)
 		log.Error(emsg)
 		return &volume.MountResponse{}, errors.New(emsg)
 	}
 	if _, ok := d.mounts[r.Name]; ok {
-		return &volume.MountResponse{Mountpoint: d.mounts[r.Name].mountpoint}, nil
+		return &volume.MountResponse{Mountpoint: d.mounts[r.Name].path}, nil
 	}
 	return &volume.MountResponse{}, nil
 }
@@ -106,15 +118,15 @@ func (d moosefsDriver) Unmount(r *volume.UnmountRequest) error {
 func (d moosefsDriver) Get(r *volume.GetRequest) (*volume.GetResponse, error) {
 	if v, ok := d.mounts[r.Name]; ok {
 		return &volume.GetResponse{
-			Volume: &volume.Volume{Name: v.name, Mountpoint: v.mountpoint}}, nil
+			Volume: &volume.Volume{Name: v.name, Mountpoint: v.path}}, nil
 	}
 	return &volume.GetResponse{}, fmt.Errorf("volume %s unknown", r.Name)
 }
 
 func (d moosefsDriver) List() (*volume.ListResponse, error) {
 	volumes := []*volume.Volume{}
 	for v := range d.mounts {
-		volumes = append(volumes, &volume.Volume{Name: d.mounts[v].name, Mountpoint: d.mounts[v].mountpoint})
+		volumes = append(volumes, &volume.Volume{Name: d.mounts[v].name, Mountpoint: d.mounts[v].path})
 	}
 	return &volume.ListResponse{Volumes: volumes}, nil
 }
@@ -135,3 +147,21 @@ func ismoosefs(mountpoint string) bool {
 	}
 	return true
 }
+
+func mkdir(path string) error {
+	fstat, err := os.Lstat(path)
+
+	if os.IsNotExist(err) {
+		if err := os.MkdirAll(path, 0755); err != nil {
+			return err
+		}
+	} else if err != nil {
+		return err
+	}
+
+	if fstat != nil && !fstat.IsDir() {
+		return fmt.Errorf("%v already exist and it's not a directory", path)
+	}
+
+	return nil
+}

main.go

@@ -13,7 +13,7 @@ import (
 )
 
 var (
-	mountpoint = flag.String("mountpoint", "/mnt/", "Host's base directory where volumes are created")
+	root = flag.String("root", "/mnt/moosefs", "Host's base directory where volumes are created")
 	verbose    = flag.Bool("verbose", false, "Enable verbose logging")
 )
 
@@ -29,7 +29,7 @@ func main() {
 	u, _ := user.Lookup("root")
 	gid, _ := strconv.Atoi(u.Gid)
 
-	d := newMooseFSDriver(*mountpoint)
+	d := newMooseFSDriver(*root)
 	h := volume.NewHandler(d)
 	fmt.Println(h.ServeUnix("moosefs", gid))
 }