Merge pull request #163 from jakirpatel/master

Added states for docker-volume-netshare.

.travis.yml

@@ -1,6 +1,6 @@
 language: go
 go:
-  - 1.7.0
+  - 1.10.1
   - tip
 script:
   - go test ./...

README.md

@@ -56,6 +56,38 @@ The method below will install the sysvinit and /etc/default options that can be
 ```
   $ sudo docker-volume-netshare nfs
 ```
+**2. Run the plugin - adding the correct DOCKER_API_VERSION**
+If you are not using the latest stable version of docker engine please specify the version with flag.
+For example:
+To check docker API version:
+```
+docker version
+Client:
+Version:	17.12.0-ce
+API version:	1.35
+Go version:	go1.9.2
+Git commit:	c97c6d6
+Built:	Wed Dec 27 20:11:19 2017
+OS/Arch:	linux/amd64
+
+Server:
+Engine:
+ Version:	17.12.0-ce
+ API version:	1.35 (minimum version 1.12)
+ Go version:	go1.9.2
+ Git commit:	c97c6d6
+ Built:	Wed Dec 27 20:09:53 2017
+ OS/Arch:	linux/amd64
+ Experimental:	false
+```
+Here the Docker API Version is 1.35. So you should start the plugin with the right version of Docker API.
+
+Minimum supported version for the plugin is 1.12.
+
+```
+  $ sudo docker-volume-netshare nfs -a 1.35
+```
+
 
 **2. Launch a container**
 
@@ -90,7 +122,7 @@ The method below will install the sysvinit and /etc/default options that can be
 **1. Run the plugin - can be added to systemd or run in the background**
 
 ```
-  $ sudo docker-volume-netshare cifs --username user --password pass --domain domain --security security
+  $ sudo docker-volume-netshare cifs --username user --password pass --domain domain --security security -a docker_api_version
 ```
 
 **2. Launch a container**
@@ -122,7 +154,7 @@ See example:
 **2. Run the plugin**
 
 ```
-  $ sudo docker-volume-netshare cifs
+  $ sudo docker-volume-netshare cifs -a docker_api_version
 ```
 
 **3. Launch a container**
@@ -140,7 +172,7 @@ options and other info can be eliminated when running a container.
 **1. Run the plugin - can be added to systemd or run in the background**
 
 ```
-  $ sudo docker-volume-netshare cifs
+  $ sudo docker-volume-netshare cifs -a docker_api_version
 ```
 
 **2. Create a Volume**

netshare/drivers/ceph.go

@@ -24,9 +24,9 @@ type cephDriver struct {
 	cephopts   map[string]string
 }
 
-func NewCephDriver(root string, username string, password string, context string, cephmount string, cephport string, localmount string, cephopts string) cephDriver {
+func NewCephDriver(root string, username string, password string, context string, cephmount string, cephport string, localmount string, cephopts string, mounts *MountManager) cephDriver {
 	d := cephDriver{
-		volumeDriver: newVolumeDriver(root),
+		volumeDriver: newVolumeDriver(root, mounts),
 		username:     username,
 		password:     password,
 		context:      context,

netshare/drivers/cifs.go

@@ -50,9 +50,9 @@ func NewCifsCredentials(user, pass, domain, security, fileMode, dirMode string)
 }
 
 // NewCIFSDriver creating the cifs driver
-func NewCIFSDriver(root string, creds *CifsCreds, netrc, cifsopts string) CifsDriver {
+func NewCIFSDriver(root string, creds *CifsCreds, netrc, cifsopts string, mounts *MountManager) CifsDriver {
 	d := CifsDriver{
-		volumeDriver: newVolumeDriver(root),
+		volumeDriver: newVolumeDriver(root, mounts),
 		creds:        creds,
 		netrc:        parseNetRC(netrc),
 		cifsopts:     map[string]string{},

netshare/drivers/driver.go

@@ -9,14 +9,14 @@ import (
 
 type volumeDriver struct {
 	root   string
-	mountm *mountManager
+	mountm *MountManager
 	m      *sync.Mutex
 }
 
-func newVolumeDriver(root string) volumeDriver {
+func newVolumeDriver(root string, mounts *MountManager) volumeDriver {
 	return volumeDriver{
 		root:   root,
-		mountm: NewVolumeManager(),
+		mountm: mounts,
 		m:      &sync.Mutex{},
 	}
 }

netshare/drivers/efs.go

@@ -22,10 +22,10 @@ type efsDriver struct {
 	dnscache map[string]string
 }
 
-func NewEFSDriver(root, nameserver string, resolve bool) efsDriver {
+func NewEFSDriver(root, nameserver string, resolve bool, mounts *MountManager) efsDriver {
 
 	d := efsDriver{
-		volumeDriver: newVolumeDriver(root),
+		volumeDriver: newVolumeDriver(root, mounts),
 		resolve:      resolve,
 		dnscache:     map[string]string{},
 	}

netshare/drivers/mounts.go

@@ -2,9 +2,13 @@ package drivers
 
 import (
 	"errors"
+	"context"
+	"strings"
+
 	log "github.com/sirupsen/logrus"
 	"github.com/docker/go-plugins-helpers/volume"
-	"strings"
+	"github.com/docker/docker/client"
+	"github.com/docker/docker/api/types"
 )
 
 const (
@@ -20,30 +24,30 @@ type mount struct {
 	managed     bool
 }
 
-type mountManager struct {
+type MountManager struct {
 	mounts map[string]*mount
 }
 
-func NewVolumeManager() *mountManager {
-	return &mountManager{
+func NewVolumeManager() *MountManager {
+	return &MountManager{
 		mounts: map[string]*mount{},
 	}
 }
 
-func (m *mountManager) HasMount(name string) bool {
+func (m *MountManager) HasMount(name string) bool {
 	_, found := m.mounts[name]
 	return found
 }
 
-func (m *mountManager) HasOptions(name string) bool {
+func (m *MountManager) HasOptions(name string) bool {
 	c, found := m.mounts[name]
 	if found {
 		return c.opts != nil && len(c.opts) > 0
 	}
 	return false
 }
 
-func (m *mountManager) HasOption(name, key string) bool {
+func (m *MountManager) HasOption(name, key string) bool {
 	if m.HasOptions(name) {
 		if _, ok := m.mounts[name].opts[key]; ok {
 			return ok
@@ -52,44 +56,44 @@ func (m *mountManager) HasOption(name, key string) bool {
 	return false
 }
 
-func (m *mountManager) GetOptions(name string) map[string]string {
+func (m *MountManager) GetOptions(name string) map[string]string {
 	if m.HasOptions(name) {
 		c, _ := m.mounts[name]
 		return c.opts
 	}
 	return map[string]string{}
 }
 
-func (m *mountManager) GetOption(name, key string) string {
+func (m *MountManager) GetOption(name, key string) string {
 	if m.HasOption(name, key) {
 		v, _ := m.mounts[name].opts[key]
 		return v
 	}
 	return ""
 }
 
-func (m *mountManager) GetOptionAsBool(name, key string) bool {
+func (m *MountManager) GetOptionAsBool(name, key string) bool {
 	rv := strings.ToLower(m.GetOption(name, key))
 	if rv == "yes" || rv == "true" {
 		return true
 	}
 	return false
 }
 
-func (m *mountManager) IsActiveMount(name string) bool {
+func (m *MountManager) IsActiveMount(name string) bool {
 	c, found := m.mounts[name]
 	return found && c.connections > 0
 }
 
-func (m *mountManager) Count(name string) int {
+func (m *MountManager) Count(name string) int {
 	c, found := m.mounts[name]
 	if found {
 		return c.connections
 	}
 	return 0
 }
 
-func (m *mountManager) Add(name, hostdir string) {
+func (m *MountManager) Add(name, hostdir string) {
 	_, found := m.mounts[name]
 	if found {
 		m.Increment(name)
@@ -98,7 +102,7 @@ func (m *mountManager) Add(name, hostdir string) {
 	}
 }
 
-func (m *mountManager) Create(name, hostdir string, opts map[string]string) *mount {
+func (m *MountManager) Create(name, hostdir string, opts map[string]string) *mount {
 	c, found := m.mounts[name]
 	if found && c.connections > 0 {
 		c.opts = opts
@@ -110,10 +114,13 @@ func (m *mountManager) Create(name, hostdir string, opts map[string]string) *mou
 	}
 }
 
-func (m *mountManager) Delete(name string) error {
-	log.Debugf("Delete volume: %s, connections: %d", name, m.Count(name))
+func (m *MountManager) Delete(name string) error {
+	// Check if any stopped containers are having references with volume.
+	refCount := checkReferences(name)
+	log.Debugf("Reference count %d", refCount)
 	if m.HasMount(name) {
-		if m.Count(name) < 1 {
+		if m.Count(name) < 1 && refCount < 1 {
+			log.Debugf("Delete volume: %s, connections: %d", name, m.Count(name))
 			delete(m.mounts, name)
 			return nil
 		}
@@ -122,32 +129,38 @@ func (m *mountManager) Delete(name string) error {
 	return nil
 }
 
-func (m *mountManager) DeleteIfNotManaged(name string) error {
+func (m *MountManager) DeleteIfNotManaged(name string) error {
 	if m.HasMount(name) && !m.IsActiveMount(name) && !m.mounts[name].managed {
 		log.Infof("Removing un-managed volume")
 		return m.Delete(name)
 	}
 	return nil
 }
 
-func (m *mountManager) Increment(name string) int {
+func (m *MountManager) Increment(name string) int {
+	log.Infof("Incrementing for %s", name)
 	c, found := m.mounts[name]
+	log.Infof("Previous connections state : %d", c.connections)
 	if found {
 		c.connections++
+		log.Infof("Current connections state : %d", c.connections)
 		return c.connections
 	}
 	return 0
 }
 
-func (m *mountManager) Decrement(name string) int {
+func (m *MountManager) Decrement(name string) int {
+	log.Infof("Decrementing for %s", name)
 	c, found := m.mounts[name]
+	log.Infof("Previous connections state : %d", c.connections)
 	if found && c.connections > 0 {
 		c.connections--
+		log.Infof("Current connections state :  %d", c.connections)
 	}
 	return 0
 }
 
-func (m *mountManager) GetVolumes(rootPath string) []*volume.Volume {
+func (m *MountManager) GetVolumes(rootPath string) []*volume.Volume {
 
 	volumes := []*volume.Volume{}
 
@@ -156,3 +169,35 @@ func (m *mountManager) GetVolumes(rootPath string) []*volume.Volume {
 	}
 	return volumes
 }
+
+func (m *MountManager) AddMount(name string, hostdir string, connections int) {
+	m.mounts[name] = &mount{name: name, hostdir: hostdir, managed: true, connections: connections}
+}
+
+//Checking volume references with started and stopped containers as well.
+func checkReferences(volumeName string) int {
+
+	cli, err := client.NewEnvClient()
+	if err != nil {
+		log.Error(err)
+	}
+
+	var counter = 0
+	ContainerListResponse, err := cli.ContainerList(context.Background(), types.ContainerListOptions{All: true}) // All : true will return the stopped containers as well.
+	if err != nil {
+		log.Fatal(err,". Use -a flag to setup the DOCKER_API_VERSION. Run 'docker-volume-netshare --help' for usage.")
+	}
+
+	for _, container := range ContainerListResponse {
+		if len(container.Mounts) == 0 {
+			continue
+		}
+		for _, mounts := range container.Mounts {
+			if !(mounts.Name == volumeName) {
+				continue
+			}
+			counter++
+		}
+	}
+	return counter
+}