volume

Documentation

Index

• Constants
• func GetPropagation(mode string) string
• func HasPropagation(mode string) bool
• func IsVolumeNameValid(name string) (bool, error)
• func ParseVolumeSource(spec string) (string, string)
• func ParseVolumesFrom(spec string) (string, string, error)
• func ReadWrite(mode string) bool
• func ValidMountMode(mode string) bool
• type Capability
• type Driver
• type LabeledVolume
• type MountPoint
  • func ParseMountSpec(spec, volumeDriver string) (*MountPoint, error)
  • func (m *MountPoint) BackwardsCompatible() bool
  • func (m *MountPoint) HasResource(absolutePath string) bool
  • func (m *MountPoint) Path() string
  • func (m *MountPoint) Setup(mountLabel string) (string, error)
  • func (m *MountPoint) Type() string
• type ScopedVolume
• type Volume

Constants

const (
	LocalScope  = "local"
	GlobalScope = "global"
)

Scopes define if a volume has is cluster-wide (global) or local only. Scopes are returned by the volume driver when it is queried for capabilities and then set on a volume

const (
	// DefaultCopyMode is the copy mode used by default for normal/named volumes
	DefaultCopyMode = true
)

const DefaultDriverName = "local"

DefaultDriverName is the driver name used for the driver implemented in the local package.

const DefaultPropagationMode string = "rprivate"

DefaultPropagationMode defines what propagation mode should be used by default if user has not specified one explicitly.

Functions

func GetPropagation

func GetPropagation(mode string) string

GetPropagation extracts and returns the mount propagation mode. If there are no specifications, then by default it is "private".

func HasPropagation

func HasPropagation(mode string) bool

HasPropagation checks if there is a valid propagation mode present in passed string. Returns true if a valid propagation mode specifier is present, false otherwise.

func IsVolumeNameValid

func IsVolumeNameValid(name string) (bool, error)

IsVolumeNameValid checks a volume name in a platform specific manner.

func ParseVolumeSource

func ParseVolumeSource(spec string) (string, string)

ParseVolumeSource parses the origin sources that's mounted into the container. It returns a name and a source. It looks to see if the spec passed in is an absolute file. If it is, it assumes the spec is a source. If not, it assumes the spec is a name.

func ParseVolumesFrom

func ParseVolumesFrom(spec string) (string, string, error)

ParseVolumesFrom ensures that the supplied volumes-from is valid.

func ReadWrite

func ReadWrite(mode string) bool

ReadWrite tells you if a mode string is a valid read-write mode or not. If there are no specifications w.r.t read write mode, then by default it returns true.

func ValidMountMode

func ValidMountMode(mode string) bool

ValidMountMode will make sure the mount mode is valid. returns if it's a valid mount mode or not.

Types

type Capability

type Capability struct {
	// Scope is the scope of the driver, `global` or `local`
	// A `global` scope indicates that the driver manages volumes across the cluster
	// A `local` scope indicates that the driver only manages volumes resources local to the host
	// Scope is declared by the driver
	Scope string
}

Capability defines a set of capabilities that a driver is able to handle.

type Driver

type Driver interface {
	// Name returns the name of the volume driver.
	Name() string
	// Create makes a new volume with the given id.
	Create(name string, opts map[string]string) (Volume, error)
	// Remove deletes the volume.
	Remove(vol Volume) (err error)
	// List lists all the volumes the driver has
	List() ([]Volume, error)
	// Get retrieves the volume with the requested name
	Get(name string) (Volume, error)
	// Scope returns the scope of the driver (e.g. `global` or `local`).
	// Scope determines how the driver is handled at a cluster level
	Scope() string
}

Driver is for creating and removing volumes.

type LabeledVolume

type LabeledVolume interface {
	Labels() map[string]string
	Volume
}

LabeledVolume wraps a Volume with user-defined labels

type MountPoint

type MountPoint struct {
	Source      string // Container host directory
	Destination string // Inside the container
	RW          bool   // True if writable
	Name        string // Name set by user
	Driver      string // Volume driver to use
	Volume      Volume `json:"-"`

	// Note Mode is not used on Windows
	Mode string `json:"Relabel"` // Originally field was `Relabel`"

	// Note Propagation is not used on Windows
	Propagation string // Mount propagation string
	Named       bool   // specifies if the mountpoint was specified by name

	// Specifies if data should be copied from the container before the first mount
	// Use a pointer here so we can tell if the user set this value explicitly
	// This allows us to error out when the user explicitly enabled copy but we can't copy due to the volume being populated
	CopyData bool `json:"-"`
	// ID is the opaque ID used to pass to the volume driver.
	// This should be set by calls to `Mount` and unset by calls to `Unmount`
	ID string
}

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.

func ParseMountSpec

func ParseMountSpec(spec, volumeDriver string) (*MountPoint, error)

ParseMountSpec validates the configuration of mount information is valid.

func (*MountPoint) BackwardsCompatible

func (m *MountPoint) BackwardsCompatible() bool

BackwardsCompatible decides whether this mount point can be used in old versions of Docker or not. Only bind mounts and local volumes can be used in old versions of Docker.

func (*MountPoint) HasResource

func (m *MountPoint) HasResource(absolutePath string) bool

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 (*MountPoint) Path

func (m *MountPoint) Path() string

Path returns the path of a volume in a mount point.

func (*MountPoint) Setup

func (m *MountPoint) Setup(mountLabel string) (string, error)

Setup sets up a mount point by either mounting the volume if it is configured, or creating the source directory if supplied.

func (*MountPoint) Type

func (m *MountPoint) Type() string

Type returns the type of mount point

type ScopedVolume

type ScopedVolume interface {
	Scope() string
	Volume
}

ScopedVolume wraps a volume with a cluster scope (e.g., `local` or `global`)

type Volume

type Volume interface {
	// Name returns the name of the volume
	Name() string
	// DriverName returns the name of the driver which owns this volume.
	DriverName() string
	// Path returns the absolute path to the volume.
	Path() string
	// Mount mounts the volume and returns the absolute path to
	// where it can be consumed.
	Mount(id string) (string, error)
	// Unmount unmounts the volume when it is no longer in use.
	Unmount(id string) error
	// Status returns low-level status information about a volume
	Status() map[string]interface{}
}

Volume is a place to store data. It is backed by a specific driver, and can be mounted.