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|
package volume
import (
"net/http"
"github.com/docker/go-plugins-helpers/sdk"
)
const (
// DefaultDockerRootDirectory is the default directory where volumes will be created.
DefaultDockerRootDirectory = "/var/lib/docker-volumes"
manifest = `{"Implements": ["VolumeDriver"]}`
createPath = "/VolumeDriver.Create"
getPath = "/VolumeDriver.Get"
listPath = "/VolumeDriver.List"
removePath = "/VolumeDriver.Remove"
hostVirtualPath = "/VolumeDriver.Path"
mountPath = "/VolumeDriver.Mount"
unmountPath = "/VolumeDriver.Unmount"
capabilitiesPath = "/VolumeDriver.Capabilities"
)
// CreateRequest is the structure that docker's requests are deserialized to.
type CreateRequest struct {
Name string
Options map[string]string `json:"Opts,omitempty"`
}
// RemoveRequest structure for a volume remove request
type RemoveRequest struct {
Name string
}
// MountRequest structure for a volume mount request
type MountRequest struct {
Name string
ID string
}
// MountResponse structure for a volume mount response
type MountResponse struct {
Mountpoint string
}
// UnmountRequest structure for a volume unmount request
type UnmountRequest struct {
Name string
ID string
}
// PathRequest structure for a volume path request
type PathRequest struct {
Name string
}
// PathResponse structure for a volume path response
type PathResponse struct {
Mountpoint string
}
// GetRequest structure for a volume get request
type GetRequest struct {
Name string
}
// GetResponse structure for a volume get response
type GetResponse struct {
Volume *Volume
}
// ListResponse structure for a volume list response
type ListResponse struct {
Volumes []*Volume
}
// CapabilitiesResponse structure for a volume capability response
type CapabilitiesResponse struct {
Capabilities Capability
}
// Volume represents a volume object for use with `Get` and `List` requests
type Volume struct {
Name string
Mountpoint string `json:",omitempty"`
CreatedAt string `json:",omitempty"`
Status map[string]interface{} `json:",omitempty"`
}
// Capability represents the list of capabilities a volume driver can return
type Capability struct {
Scope string
}
// ErrorResponse is a formatted error message that docker can understand
type ErrorResponse struct {
Err string
}
// NewErrorResponse creates an ErrorResponse with the provided message
func NewErrorResponse(msg string) *ErrorResponse {
return &ErrorResponse{Err: msg}
}
// Driver represent the interface a driver must fulfill.
type Driver interface {
Create(*CreateRequest) error
List() (*ListResponse, error)
Get(*GetRequest) (*GetResponse, error)
Remove(*RemoveRequest) error
Path(*PathRequest) (*PathResponse, error)
Mount(*MountRequest) (*MountResponse, error)
Unmount(*UnmountRequest) error
Capabilities() *CapabilitiesResponse
}
// Handler forwards requests and responses between the docker daemon and the plugin.
type Handler struct {
driver Driver
sdk.Handler
}
// NewHandler initializes the request handler with a driver implementation.
func NewHandler(driver Driver) *Handler {
h := &Handler{driver, sdk.NewHandler(manifest)}
h.initMux()
return h
}
func (h *Handler) initMux() {
h.HandleFunc(createPath, func(w http.ResponseWriter, r *http.Request) {
req := &CreateRequest{}
err := sdk.DecodeRequest(w, r, req)
if err != nil {
return
}
err = h.driver.Create(req)
if err != nil {
sdk.EncodeResponse(w, NewErrorResponse(err.Error()), true)
return
}
sdk.EncodeResponse(w, struct{}{}, false)
})
h.HandleFunc(removePath, func(w http.ResponseWriter, r *http.Request) {
req := &RemoveRequest{}
err := sdk.DecodeRequest(w, r, req)
if err != nil {
return
}
err = h.driver.Remove(req)
if err != nil {
sdk.EncodeResponse(w, NewErrorResponse(err.Error()), true)
return
}
sdk.EncodeResponse(w, struct{}{}, false)
})
h.HandleFunc(mountPath, func(w http.ResponseWriter, r *http.Request) {
req := &MountRequest{}
err := sdk.DecodeRequest(w, r, req)
if err != nil {
return
}
res, err := h.driver.Mount(req)
if err != nil {
sdk.EncodeResponse(w, NewErrorResponse(err.Error()), true)
return
}
sdk.EncodeResponse(w, res, false)
})
h.HandleFunc(hostVirtualPath, func(w http.ResponseWriter, r *http.Request) {
req := &PathRequest{}
err := sdk.DecodeRequest(w, r, req)
if err != nil {
return
}
res, err := h.driver.Path(req)
if err != nil {
sdk.EncodeResponse(w, NewErrorResponse(err.Error()), true)
return
}
sdk.EncodeResponse(w, res, false)
})
h.HandleFunc(getPath, func(w http.ResponseWriter, r *http.Request) {
req := &GetRequest{}
err := sdk.DecodeRequest(w, r, req)
if err != nil {
return
}
res, err := h.driver.Get(req)
if err != nil {
sdk.EncodeResponse(w, NewErrorResponse(err.Error()), true)
return
}
sdk.EncodeResponse(w, res, false)
})
h.HandleFunc(unmountPath, func(w http.ResponseWriter, r *http.Request) {
req := &UnmountRequest{}
err := sdk.DecodeRequest(w, r, req)
if err != nil {
return
}
err = h.driver.Unmount(req)
if err != nil {
sdk.EncodeResponse(w, NewErrorResponse(err.Error()), true)
return
}
sdk.EncodeResponse(w, struct{}{}, false)
})
h.HandleFunc(listPath, func(w http.ResponseWriter, r *http.Request) {
res, err := h.driver.List()
if err != nil {
sdk.EncodeResponse(w, NewErrorResponse(err.Error()), true)
return
}
sdk.EncodeResponse(w, res, false)
})
h.HandleFunc(capabilitiesPath, func(w http.ResponseWriter, r *http.Request) {
sdk.EncodeResponse(w, h.driver.Capabilities(), false)
})
}
|
