package volume import ( "log" "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) { log.Println("Entering go-plugins-helpers createPath") 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) { log.Println("Entering go-plugins-helpers removePath") 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) { log.Println("Entering go-plugins-helpers mountPath") 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) { log.Println("Entering go-plugins-helpers hostVirtualPath") 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) { log.Println("Entering go-plugins-helpers getPath") 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) { log.Println("Entering go-plugins-helpers unmountPath") 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) { log.Println("Entering go-plugins-helpers listPath") 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) { log.Println("Entering go-plugins-helpers capabilitiesPath") sdk.EncodeResponse(w, h.driver.Capabilities(), false) }) }