moby/daemon/volumes.go
David Calavera 72bb56618b Move volume ref counting store to a package.
- Add unit tests to make sure the functionality is correct.
- Add FilterByDriver to allow filtering volumes by driver, for future
  `volume ls` filtering and whatnot.

Signed-off-by: David Calavera <david.calavera@gmail.com>
2015-09-21 12:46:49 -04:00

109 lines
3 KiB
Go

package daemon
import (
"errors"
"fmt"
"io/ioutil"
"os"
"path/filepath"
"strings"
"github.com/Sirupsen/logrus"
"github.com/docker/docker/api/types"
derr "github.com/docker/docker/errors"
"github.com/docker/docker/pkg/chrootarchive"
"github.com/docker/docker/pkg/system"
"github.com/docker/docker/volume"
)
var (
// ErrVolumeReadonly is used to signal an error when trying to copy data into
// a volume mount that is not writable.
ErrVolumeReadonly = errors.New("mounted volume is marked read-only")
)
// mountPoint is the intersection point between a volume and a container. It
// specifies which volume is to be used and where inside a container it should
// be mounted.
type mountPoint struct {
Name string
Destination string
Driver string
RW bool
Volume volume.Volume `json:"-"`
Source string
Mode string `json:"Relabel"` // Originally field was `Relabel`"
}
// Setup sets up a mount point by either mounting the volume if it is
// configured, or creating the source directory if supplied.
func (m *mountPoint) Setup() (string, error) {
if m.Volume != nil {
return m.Volume.Mount()
}
if len(m.Source) > 0 {
if _, err := os.Stat(m.Source); err != nil {
if !os.IsNotExist(err) {
return "", err
}
logrus.Warnf("Auto-creating non-existant volume host path %s, this is deprecated and will be removed soon", m.Source)
if err := system.MkdirAll(m.Source, 0755); err != nil {
return "", err
}
}
return m.Source, nil
}
return "", derr.ErrorCodeMountSetup
}
// hasResource checks whether the given absolute path for a container is in
// this mount point. If the relative path starts with `../` then the resource
// is outside of this mount point, but we can't simply check for this prefix
// because it misses `..` which is also outside of the mount, so check both.
func (m *mountPoint) hasResource(absolutePath string) bool {
relPath, err := filepath.Rel(m.Destination, absolutePath)
return err == nil && relPath != ".." && !strings.HasPrefix(relPath, fmt.Sprintf("..%c", filepath.Separator))
}
// Path returns the path of a volume in a mount point.
func (m *mountPoint) Path() string {
if m.Volume != nil {
return m.Volume.Path()
}
return m.Source
}
// copyExistingContents copies from the source to the destination and
// ensures the ownership is appropriately set.
func copyExistingContents(source, destination string) error {
volList, err := ioutil.ReadDir(source)
if err != nil {
return err
}
if len(volList) > 0 {
srcList, err := ioutil.ReadDir(destination)
if err != nil {
return err
}
if len(srcList) == 0 {
// If the source volume is empty copy files from the root into the volume
if err := chrootarchive.CopyWithTar(source, destination); err != nil {
return err
}
}
}
return copyOwnership(source, destination)
}
// volumeToAPIType converts a volume.Volume to the type used by the remote API
func volumeToAPIType(v volume.Volume) *types.Volume {
return &types.Volume{
Name: v.Name(),
Driver: v.DriverName(),
Mountpoint: v.Path(),
}
}