rclone/fs/fs.go
2018-10-06 11:47:46 +01:00

1107 lines
33 KiB
Go

// Package fs is a generic file system interface for rclone object storage systems
package fs
import (
"fmt"
"io"
"io/ioutil"
"log"
"math"
"os"
"path/filepath"
"reflect"
"sort"
"strings"
"time"
"github.com/ncw/rclone/fs/config/configmap"
"github.com/ncw/rclone/fs/config/configstruct"
"github.com/ncw/rclone/fs/fspath"
"github.com/ncw/rclone/fs/hash"
"github.com/pkg/errors"
)
// EntryType can be associated with remote paths to identify their type
type EntryType int
// Constants
const (
// ModTimeNotSupported is a very large precision value to show
// mod time isn't supported on this Fs
ModTimeNotSupported = 100 * 365 * 24 * time.Hour
// MaxLevel is a sentinel representing an infinite depth for listings
MaxLevel = math.MaxInt32
// EntryDirectory should be used to classify remote paths in directories
EntryDirectory EntryType = iota // 0
// EntryObject should be used to classify remote paths in objects
EntryObject // 1
)
// Globals
var (
// Filesystem registry
Registry []*RegInfo
// ErrorNotFoundInConfigFile is returned by NewFs if not found in config file
ErrorNotFoundInConfigFile = errors.New("didn't find section in config file")
ErrorCantPurge = errors.New("can't purge directory")
ErrorCantCopy = errors.New("can't copy object - incompatible remotes")
ErrorCantMove = errors.New("can't move object - incompatible remotes")
ErrorCantDirMove = errors.New("can't move directory - incompatible remotes")
ErrorDirExists = errors.New("can't copy directory - destination already exists")
ErrorCantSetModTime = errors.New("can't set modified time")
ErrorCantSetModTimeWithoutDelete = errors.New("can't set modified time without deleting existing object")
ErrorDirNotFound = errors.New("directory not found")
ErrorObjectNotFound = errors.New("object not found")
ErrorLevelNotSupported = errors.New("level value not supported")
ErrorListAborted = errors.New("list aborted")
ErrorListBucketRequired = errors.New("bucket or container name is needed in remote")
ErrorIsFile = errors.New("is a file not a directory")
ErrorNotAFile = errors.New("is a not a regular file")
ErrorNotDeleting = errors.New("not deleting files as there were IO errors")
ErrorNotDeletingDirs = errors.New("not deleting directories as there were IO errors")
ErrorCantMoveOverlapping = errors.New("can't move files on overlapping remotes")
ErrorDirectoryNotEmpty = errors.New("directory not empty")
ErrorImmutableModified = errors.New("immutable file modified")
ErrorPermissionDenied = errors.New("permission denied")
)
// RegInfo provides information about a filesystem
type RegInfo struct {
// Name of this fs
Name string
// Description of this fs - defaults to Name
Description string
// Prefix for command line flags for this fs - defaults to Name if not set
Prefix string
// Create a new file system. If root refers to an existing
// object, then it should return a Fs which which points to
// the parent of that object and ErrorIsFile.
NewFs func(name string, root string, config configmap.Mapper) (Fs, error) `json:"-"`
// Function to call to help with config
Config func(name string, config configmap.Mapper) `json:"-"`
// Options for the Fs configuration
Options Options
}
// FileName returns the on disk file name for this backend
func (ri *RegInfo) FileName() string {
return strings.Replace(ri.Name, " ", "", -1)
}
// Options is a slice of configuration Option for a backend
type Options []Option
// Set the default values for the options
func (os Options) setValues() {
for i := range os {
o := &os[i]
if o.Default == nil {
o.Default = ""
}
}
}
// OptionVisibility controls whether the options are visible in the
// configurator or the command line.
type OptionVisibility byte
// Constants Option.Hide
const (
OptionHideCommandLine OptionVisibility = 1 << iota
OptionHideConfigurator
OptionHideBoth = OptionHideCommandLine | OptionHideConfigurator
)
// Option is describes an option for the config wizard
//
// This also describes command line options and environment variables
type Option struct {
Name string // name of the option in snake_case
Help string // Help, the first line only is used for the command line help
Provider string // Set to filter on provider
Default interface{} // default value, nil => ""
Value interface{} // value to be set by flags
Examples OptionExamples `json:",omitempty"` // config examples
ShortOpt string // the short option for this if required
Hide OptionVisibility // set this to hide the config from the configurator or the command line
Required bool // this option is required
IsPassword bool // set if the option is a password
NoPrefix bool // set if the option for this should not use the backend prefix
Advanced bool // set if this is an advanced config option
}
// GetValue gets the current current value which is the default if not set
func (o *Option) GetValue() interface{} {
val := o.Value
if val == nil {
val = o.Default
}
return val
}
// String turns Option into a string
func (o *Option) String() string {
return fmt.Sprint(o.GetValue())
}
// Set a Option from a string
func (o *Option) Set(s string) (err error) {
newValue, err := configstruct.StringToInterface(o.GetValue(), s)
if err != nil {
return err
}
o.Value = newValue
return nil
}
// Type of the value
func (o *Option) Type() string {
return reflect.TypeOf(o.GetValue()).Name()
}
// FlagName for the option
func (o *Option) FlagName(prefix string) string {
name := strings.Replace(o.Name, "_", "-", -1) // convert snake_case to kebab-case
if !o.NoPrefix {
name = prefix + "-" + name
}
return name
}
// EnvVarName for the option
func (o *Option) EnvVarName(prefix string) string {
return OptionToEnv(prefix + "-" + o.Name)
}
// OptionExamples is a slice of examples
type OptionExamples []OptionExample
// Len is part of sort.Interface.
func (os OptionExamples) Len() int { return len(os) }
// Swap is part of sort.Interface.
func (os OptionExamples) Swap(i, j int) { os[i], os[j] = os[j], os[i] }
// Less is part of sort.Interface.
func (os OptionExamples) Less(i, j int) bool { return os[i].Help < os[j].Help }
// Sort sorts an OptionExamples
func (os OptionExamples) Sort() { sort.Sort(os) }
// OptionExample describes an example for an Option
type OptionExample struct {
Value string
Help string
Provider string
}
// Register a filesystem
//
// Fs modules should use this in an init() function
func Register(info *RegInfo) {
info.Options.setValues()
if info.Prefix == "" {
info.Prefix = info.Name
}
Registry = append(Registry, info)
}
// Fs is the interface a cloud storage system must provide
type Fs interface {
Info
// List the objects and directories in dir into entries. The
// entries can be returned in any order but should be for a
// complete directory.
//
// dir should be "" to list the root, and should not have
// trailing slashes.
//
// This should return ErrDirNotFound if the directory isn't
// found.
List(dir string) (entries DirEntries, err error)
// NewObject finds the Object at remote. If it can't be found
// it returns the error ErrorObjectNotFound.
NewObject(remote string) (Object, error)
// Put in to the remote path with the modTime given of the given size
//
// May create the object even if it returns an error - if so
// will return the object and the error, otherwise will return
// nil and the error
Put(in io.Reader, src ObjectInfo, options ...OpenOption) (Object, error)
// Mkdir makes the directory (container, bucket)
//
// Shouldn't return an error if it already exists
Mkdir(dir string) error
// Rmdir removes the directory (container, bucket) if empty
//
// Return an error if it doesn't exist or isn't empty
Rmdir(dir string) error
}
// Info provides a read only interface to information about a filesystem.
type Info interface {
// Name of the remote (as passed into NewFs)
Name() string
// Root of the remote (as passed into NewFs)
Root() string
// String returns a description of the FS
String() string
// Precision of the ModTimes in this Fs
Precision() time.Duration
// Returns the supported hash types of the filesystem
Hashes() hash.Set
// Features returns the optional features of this Fs
Features() *Features
}
// Object is a filesystem like object provided by an Fs
type Object interface {
ObjectInfo
// SetModTime sets the metadata on the object to set the modification date
SetModTime(time.Time) error
// Open opens the file for read. Call Close() on the returned io.ReadCloser
Open(options ...OpenOption) (io.ReadCloser, error)
// Update in to the object with the modTime given of the given size
Update(in io.Reader, src ObjectInfo, options ...OpenOption) error
// Removes this object
Remove() error
}
// ObjectInfo provides read only information about an object.
type ObjectInfo interface {
DirEntry
// Fs returns read only access to the Fs that this object is part of
Fs() Info
// Hash returns the selected checksum of the file
// If no checksum is available it returns ""
Hash(hash.Type) (string, error)
// Storable says whether this object can be stored
Storable() bool
}
// DirEntry provides read only information about the common subset of
// a Dir or Object. These are returned from directory listings - type
// assert them into the correct type.
type DirEntry interface {
// String returns a description of the Object
String() string
// Remote returns the remote path
Remote() string
// ModTime returns the modification date of the file
// It should return a best guess if one isn't available
ModTime() time.Time
// Size returns the size of the file
Size() int64
}
// Directory is a filesystem like directory provided by an Fs
type Directory interface {
DirEntry
// Items returns the count of items in this directory or this
// directory and subdirectories if known, -1 for unknown
Items() int64
// ID returns the internal ID of this directory if known, or
// "" otherwise
ID() string
}
// MimeTyper is an optional interface for Object
type MimeTyper interface {
// MimeType returns the content type of the Object if
// known, or "" if not
MimeType() string
}
// IDer is an optional interface for Object
type IDer interface {
// ID returns the ID of the Object if known, or "" if not
ID() string
}
// ObjectUnWrapper is an optional interface for Object
type ObjectUnWrapper interface {
// UnWrap returns the Object that this Object is wrapping or
// nil if it isn't wrapping anything
UnWrap() Object
}
// SetTierer is an optional interface for Object
type SetTierer interface {
// SetTier performs changing storage tier of the Object if
// multiple storage classes supported
SetTier(tier string) error
}
// GetTierer is an optional interface for Object
type GetTierer interface {
// GetTier returns storage tier or class of the Object
GetTier() string
}
// ListRCallback defines a callback function for ListR to use
//
// It is called for each tranche of entries read from the listing and
// if it returns an error, the listing stops.
type ListRCallback func(entries DirEntries) error
// ListRFn is defines the call used to recursively list a directory
type ListRFn func(dir string, callback ListRCallback) error
// NewUsageValue makes a valid value
func NewUsageValue(value int64) *int64 {
p := new(int64)
*p = value
return p
}
// Usage is returned by the About call
//
// If a value is nil then it isn't supported by that backend
type Usage struct {
Total *int64 `json:"total,omitempty"` // quota of bytes that can be used
Used *int64 `json:"used,omitempty"` // bytes in use
Trashed *int64 `json:"trashed,omitempty"` // bytes in trash
Other *int64 `json:"other,omitempty"` // other usage eg gmail in drive
Free *int64 `json:"free,omitempty"` // bytes which can be uploaded before reaching the quota
Objects *int64 `json:"objects,omitempty"` // objects in the storage system
}
// Features describe the optional features of the Fs
type Features struct {
// Feature flags, whether Fs
CaseInsensitive bool // has case insensitive files
DuplicateFiles bool // allows duplicate files
ReadMimeType bool // can read the mime type of objects
WriteMimeType bool // can set the mime type of objects
CanHaveEmptyDirectories bool // can have empty directories
BucketBased bool // is bucket based (like s3, swift etc)
SetTier bool // allows set tier functionality on objects
GetTier bool // allows to retrieve storage tier of objects
// Purge all files in the root and the root directory
//
// Implement this if you have a way of deleting all the files
// quicker than just running Remove() on the result of List()
//
// Return an error if it doesn't exist
Purge func() error
// Copy src to this remote using server side copy operations.
//
// This is stored with the remote path given
//
// It returns the destination Object and a possible error
//
// Will only be called if src.Fs().Name() == f.Name()
//
// If it isn't possible then return fs.ErrorCantCopy
Copy func(src Object, remote string) (Object, error)
// Move src to this remote using server side move operations.
//
// This is stored with the remote path given
//
// It returns the destination Object and a possible error
//
// Will only be called if src.Fs().Name() == f.Name()
//
// If it isn't possible then return fs.ErrorCantMove
Move func(src Object, remote string) (Object, error)
// DirMove moves src, srcRemote to this remote at dstRemote
// using server side move operations.
//
// Will only be called if src.Fs().Name() == f.Name()
//
// If it isn't possible then return fs.ErrorCantDirMove
//
// If destination exists then return fs.ErrorDirExists
DirMove func(src Fs, srcRemote, dstRemote string) error
// ChangeNotify calls the passed function with a path
// that has had changes. If the implementation
// uses polling, it should adhere to the given interval.
ChangeNotify func(func(string, EntryType), <-chan time.Duration)
// UnWrap returns the Fs that this Fs is wrapping
UnWrap func() Fs
// WrapFs returns the Fs that is wrapping this Fs
WrapFs func() Fs
// SetWrapper sets the Fs that is wrapping this Fs
SetWrapper func(f Fs)
// DirCacheFlush resets the directory cache - used in testing
// as an optional interface
DirCacheFlush func()
// PublicLink generates a public link to the remote path (usually readable by anyone)
PublicLink func(remote string) (string, error)
// Put in to the remote path with the modTime given of the given size
//
// May create the object even if it returns an error - if so
// will return the object and the error, otherwise will return
// nil and the error
//
// May create duplicates or return errors if src already
// exists.
PutUnchecked func(in io.Reader, src ObjectInfo, options ...OpenOption) (Object, error)
// PutStream uploads to the remote path with the modTime given of indeterminate size
//
// May create the object even if it returns an error - if so
// will return the object and the error, otherwise will return
// nil and the error
PutStream func(in io.Reader, src ObjectInfo, options ...OpenOption) (Object, error)
// MergeDirs merges the contents of all the directories passed
// in into the first one and rmdirs the other directories.
MergeDirs func([]Directory) error
// CleanUp the trash in the Fs
//
// Implement this if you have a way of emptying the trash or
// otherwise cleaning up old versions of files.
CleanUp func() error
// ListR lists the objects and directories of the Fs starting
// from dir recursively into out.
//
// dir should be "" to start from the root, and should not
// have trailing slashes.
//
// This should return ErrDirNotFound if the directory isn't
// found.
//
// It should call callback for each tranche of entries read.
// These need not be returned in any particular order. If
// callback returns an error then the listing will stop
// immediately.
//
// Don't implement this unless you have a more efficient way
// of listing recursively that doing a directory traversal.
ListR ListRFn
// About gets quota information from the Fs
About func() (*Usage, error)
}
// Disable nil's out the named feature. If it isn't found then it
// will log a message.
func (ft *Features) Disable(name string) *Features {
v := reflect.ValueOf(ft).Elem()
vType := v.Type()
for i := 0; i < v.NumField(); i++ {
vName := vType.Field(i).Name
field := v.Field(i)
if strings.EqualFold(name, vName) {
if !field.CanSet() {
Errorf(nil, "Can't set Feature %q", name)
} else {
zero := reflect.Zero(field.Type())
field.Set(zero)
Debugf(nil, "Reset feature %q", name)
}
}
}
return ft
}
// List returns a slice of all the possible feature names
func (ft *Features) List() (out []string) {
v := reflect.ValueOf(ft).Elem()
vType := v.Type()
for i := 0; i < v.NumField(); i++ {
out = append(out, vType.Field(i).Name)
}
return out
}
// DisableList nil's out the comma separated list of named features.
// If it isn't found then it will log a message.
func (ft *Features) DisableList(list []string) *Features {
for _, feature := range list {
ft.Disable(strings.TrimSpace(feature))
}
return ft
}
// Fill fills in the function pointers in the Features struct from the
// optional interfaces. It returns the original updated Features
// struct passed in.
func (ft *Features) Fill(f Fs) *Features {
if do, ok := f.(Purger); ok {
ft.Purge = do.Purge
}
if do, ok := f.(Copier); ok {
ft.Copy = do.Copy
}
if do, ok := f.(Mover); ok {
ft.Move = do.Move
}
if do, ok := f.(DirMover); ok {
ft.DirMove = do.DirMove
}
if do, ok := f.(ChangeNotifier); ok {
ft.ChangeNotify = do.ChangeNotify
}
if do, ok := f.(UnWrapper); ok {
ft.UnWrap = do.UnWrap
}
if do, ok := f.(Wrapper); ok {
ft.WrapFs = do.WrapFs
ft.SetWrapper = do.SetWrapper
}
if do, ok := f.(DirCacheFlusher); ok {
ft.DirCacheFlush = do.DirCacheFlush
}
if do, ok := f.(PublicLinker); ok {
ft.PublicLink = do.PublicLink
}
if do, ok := f.(PutUncheckeder); ok {
ft.PutUnchecked = do.PutUnchecked
}
if do, ok := f.(PutStreamer); ok {
ft.PutStream = do.PutStream
}
if do, ok := f.(MergeDirser); ok {
ft.MergeDirs = do.MergeDirs
}
if do, ok := f.(CleanUpper); ok {
ft.CleanUp = do.CleanUp
}
if do, ok := f.(ListRer); ok {
ft.ListR = do.ListR
}
if do, ok := f.(Abouter); ok {
ft.About = do.About
}
return ft.DisableList(Config.DisableFeatures)
}
// Mask the Features with the Fs passed in
//
// Only optional features which are implemented in both the original
// Fs AND the one passed in will be advertised. Any features which
// aren't in both will be set to false/nil, except for UnWrap/Wrap which
// will be left untouched.
func (ft *Features) Mask(f Fs) *Features {
mask := f.Features()
ft.CaseInsensitive = ft.CaseInsensitive && mask.CaseInsensitive
ft.DuplicateFiles = ft.DuplicateFiles && mask.DuplicateFiles
ft.ReadMimeType = ft.ReadMimeType && mask.ReadMimeType
ft.WriteMimeType = ft.WriteMimeType && mask.WriteMimeType
ft.CanHaveEmptyDirectories = ft.CanHaveEmptyDirectories && mask.CanHaveEmptyDirectories
ft.BucketBased = ft.BucketBased && mask.BucketBased
ft.SetTier = ft.SetTier && mask.SetTier
ft.GetTier = ft.GetTier && mask.GetTier
if mask.Purge == nil {
ft.Purge = nil
}
if mask.Copy == nil {
ft.Copy = nil
}
if mask.Move == nil {
ft.Move = nil
}
if mask.DirMove == nil {
ft.DirMove = nil
}
if mask.ChangeNotify == nil {
ft.ChangeNotify = nil
}
// if mask.UnWrap == nil {
// ft.UnWrap = nil
// }
if mask.DirCacheFlush == nil {
ft.DirCacheFlush = nil
}
if mask.PutUnchecked == nil {
ft.PutUnchecked = nil
}
if mask.PutStream == nil {
ft.PutStream = nil
}
if mask.MergeDirs == nil {
ft.MergeDirs = nil
}
if mask.CleanUp == nil {
ft.CleanUp = nil
}
if mask.ListR == nil {
ft.ListR = nil
}
if mask.About == nil {
ft.About = nil
}
return ft.DisableList(Config.DisableFeatures)
}
// Wrap makes a Copy of the features passed in, overriding the UnWrap/Wrap
// method only if available in f.
func (ft *Features) Wrap(f Fs) *Features {
ftCopy := new(Features)
*ftCopy = *ft
if do, ok := f.(UnWrapper); ok {
ftCopy.UnWrap = do.UnWrap
}
if do, ok := f.(Wrapper); ok {
ftCopy.WrapFs = do.WrapFs
ftCopy.SetWrapper = do.SetWrapper
}
return ftCopy
}
// WrapsFs adds extra information between `f` which wraps `w`
func (ft *Features) WrapsFs(f Fs, w Fs) *Features {
wFeatures := w.Features()
if wFeatures.WrapFs != nil && wFeatures.SetWrapper != nil {
wFeatures.SetWrapper(f)
}
return ft
}
// Purger is an optional interfaces for Fs
type Purger interface {
// Purge all files in the root and the root directory
//
// Implement this if you have a way of deleting all the files
// quicker than just running Remove() on the result of List()
//
// Return an error if it doesn't exist
Purge() error
}
// Copier is an optional interface for Fs
type Copier interface {
// Copy src to this remote using server side copy operations.
//
// This is stored with the remote path given
//
// It returns the destination Object and a possible error
//
// Will only be called if src.Fs().Name() == f.Name()
//
// If it isn't possible then return fs.ErrorCantCopy
Copy(src Object, remote string) (Object, error)
}
// Mover is an optional interface for Fs
type Mover interface {
// Move src to this remote using server side move operations.
//
// This is stored with the remote path given
//
// It returns the destination Object and a possible error
//
// Will only be called if src.Fs().Name() == f.Name()
//
// If it isn't possible then return fs.ErrorCantMove
Move(src Object, remote string) (Object, error)
}
// DirMover is an optional interface for Fs
type DirMover interface {
// DirMove moves src, srcRemote to this remote at dstRemote
// using server side move operations.
//
// Will only be called if src.Fs().Name() == f.Name()
//
// If it isn't possible then return fs.ErrorCantDirMove
//
// If destination exists then return fs.ErrorDirExists
DirMove(src Fs, srcRemote, dstRemote string) error
}
// ChangeNotifier is an optional interface for Fs
type ChangeNotifier interface {
// ChangeNotify calls the passed function with a path
// that has had changes. If the implementation
// uses polling, it should adhere to the given interval.
// At least one value will be written to the channel,
// specifying the initial value and updated values might
// follow. A 0 Duration should pause the polling.
// The ChangeNotify implemantion must empty the channel
// regulary. When the channel gets closed, the implemantion
// should stop polling and release resources.
ChangeNotify(func(string, EntryType), <-chan time.Duration)
}
// UnWrapper is an optional interfaces for Fs
type UnWrapper interface {
// UnWrap returns the Fs that this Fs is wrapping
UnWrap() Fs
}
// Wrapper is an optional interfaces for Fs
type Wrapper interface {
// Wrap returns the Fs that is wrapping this Fs
WrapFs() Fs
// SetWrapper sets the Fs that is wrapping this Fs
SetWrapper(f Fs)
}
// DirCacheFlusher is an optional interface for Fs
type DirCacheFlusher interface {
// DirCacheFlush resets the directory cache - used in testing
// as an optional interface
DirCacheFlush()
}
// PutUncheckeder is an optional interface for Fs
type PutUncheckeder interface {
// Put in to the remote path with the modTime given of the given size
//
// May create the object even if it returns an error - if so
// will return the object and the error, otherwise will return
// nil and the error
//
// May create duplicates or return errors if src already
// exists.
PutUnchecked(in io.Reader, src ObjectInfo, options ...OpenOption) (Object, error)
}
// PutStreamer is an optional interface for Fs
type PutStreamer interface {
// PutStream uploads to the remote path with the modTime given of indeterminate size
//
// May create the object even if it returns an error - if so
// will return the object and the error, otherwise will return
// nil and the error
PutStream(in io.Reader, src ObjectInfo, options ...OpenOption) (Object, error)
}
// PublicLinker is an optional interface for Fs
type PublicLinker interface {
// PublicLink generates a public link to the remote path (usually readable by anyone)
PublicLink(remote string) (string, error)
}
// MergeDirser is an option interface for Fs
type MergeDirser interface {
// MergeDirs merges the contents of all the directories passed
// in into the first one and rmdirs the other directories.
MergeDirs([]Directory) error
}
// CleanUpper is an optional interfaces for Fs
type CleanUpper interface {
// CleanUp the trash in the Fs
//
// Implement this if you have a way of emptying the trash or
// otherwise cleaning up old versions of files.
CleanUp() error
}
// ListRer is an optional interfaces for Fs
type ListRer interface {
// ListR lists the objects and directories of the Fs starting
// from dir recursively into out.
//
// dir should be "" to start from the root, and should not
// have trailing slashes.
//
// This should return ErrDirNotFound if the directory isn't
// found.
//
// It should call callback for each tranche of entries read.
// These need not be returned in any particular order. If
// callback returns an error then the listing will stop
// immediately.
//
// Don't implement this unless you have a more efficient way
// of listing recursively that doing a directory traversal.
ListR(dir string, callback ListRCallback) error
}
// RangeSeeker is the interface that wraps the RangeSeek method.
//
// Some of the returns from Object.Open() may optionally implement
// this method for efficiency purposes.
type RangeSeeker interface {
// RangeSeek behaves like a call to Seek(offset int64, whence
// int) with the output wrapped in an io.LimitedReader
// limiting the total length to limit.
//
// RangeSeek with a limit of < 0 is equivalent to a regular Seek.
RangeSeek(offset int64, whence int, length int64) (int64, error)
}
// Abouter is an optional interface for Fs
type Abouter interface {
// About gets quota information from the Fs
About() (*Usage, error)
}
// ObjectsChan is a channel of Objects
type ObjectsChan chan Object
// Objects is a slice of Object~s
type Objects []Object
// ObjectPair is a pair of Objects used to describe a potential copy
// operation.
type ObjectPair struct {
Src, Dst Object
}
// Find looks for an RegInfo object for the name passed in. The name
// can be either the Name or the Prefix.
//
// Services are looked up in the config file
func Find(name string) (*RegInfo, error) {
for _, item := range Registry {
if item.Name == name || item.Prefix == name || item.FileName() == name {
return item, nil
}
}
return nil, errors.Errorf("didn't find backend called %q", name)
}
// MustFind looks for an Info object for the type name passed in
//
// Services are looked up in the config file
//
// Exits with a fatal error if not found
func MustFind(name string) *RegInfo {
fs, err := Find(name)
if err != nil {
log.Fatalf("Failed to find remote: %v", err)
}
return fs
}
// ParseRemote deconstructs a path into configName, fsPath, looking up
// the fsName in the config file (returning NotFoundInConfigFile if not found)
func ParseRemote(path string) (fsInfo *RegInfo, configName, fsPath string, err error) {
configName, fsPath = fspath.Parse(path)
var fsName string
var ok bool
if configName != "" {
if strings.HasPrefix(configName, ":") {
fsName = configName[1:]
} else {
m := ConfigMap(nil, configName)
fsName, ok = m.Get("type")
if !ok {
return nil, "", "", ErrorNotFoundInConfigFile
}
}
} else {
fsName = "local"
configName = "local"
}
fsInfo, err = Find(fsName)
return fsInfo, configName, fsPath, err
}
// A configmap.Getter to read from the environment RCLONE_CONFIG_backend_option_name
type configEnvVars string
// Get a config item from the environment variables if possible
func (configName configEnvVars) Get(key string) (value string, ok bool) {
return os.LookupEnv(ConfigToEnv(string(configName), key))
}
// A configmap.Getter to read from the environment RCLONE_option_name
type optionEnvVars string
// Get a config item from the option environment variables if possible
func (prefix optionEnvVars) Get(key string) (value string, ok bool) {
return os.LookupEnv(OptionToEnv(string(prefix) + "-" + key))
}
// A configmap.Getter to read either the default value or the set
// value from the RegInfo.Options
type regInfoValues struct {
fsInfo *RegInfo
useDefault bool
}
// override the values in configMap with the either the flag values or
// the default values
func (r *regInfoValues) Get(key string) (value string, ok bool) {
for i := range r.fsInfo.Options {
o := &r.fsInfo.Options[i]
if o.Name == key {
if r.useDefault || o.Value != nil {
return o.String(), true
}
break
}
}
return "", false
}
// A configmap.Setter to read from the config file
type setConfigFile string
// Set a config item into the config file
func (section setConfigFile) Set(key, value string) {
Debugf(nil, "Saving config %q = %q in section %q of the config file", key, value, section)
ConfigFileSet(string(section), key, value)
}
// A configmap.Getter to read from the config file
type getConfigFile string
// Get a config item from the config file
func (section getConfigFile) Get(key string) (value string, ok bool) {
value, ok = ConfigFileGet(string(section), key)
// Ignore empty lines in the config file
if value == "" {
ok = false
}
return value, ok
}
// ConfigMap creates a configmap.Map from the *RegInfo and the
// configName passed in.
//
// If fsInfo is nil then the returned configmap.Map should only be
// used for reading non backend specific parameters, such as "type".
func ConfigMap(fsInfo *RegInfo, configName string) (config *configmap.Map) {
// Create the config
config = configmap.New()
// Read the config, more specific to least specific
// flag values
if fsInfo != nil {
config.AddGetter(&regInfoValues{fsInfo, false})
}
// remote specific environment vars
config.AddGetter(configEnvVars(configName))
// backend specific environment vars
if fsInfo != nil {
config.AddGetter(optionEnvVars(fsInfo.Prefix))
}
// config file
config.AddGetter(getConfigFile(configName))
// default values
if fsInfo != nil {
config.AddGetter(&regInfoValues{fsInfo, true})
}
// Set Config
config.AddSetter(setConfigFile(configName))
return config
}
// ConfigFs makes the config for calling NewFs with.
//
// It parses the path which is of the form remote:path
//
// Remotes are looked up in the config file. If the remote isn't
// found then NotFoundInConfigFile will be returned.
func ConfigFs(path string) (fsInfo *RegInfo, configName, fsPath string, config *configmap.Map, err error) {
// Parse the remote path
fsInfo, configName, fsPath, err = ParseRemote(path)
if err != nil {
return
}
config = ConfigMap(fsInfo, configName)
return
}
// NewFs makes a new Fs object from the path
//
// The path is of the form remote:path
//
// Remotes are looked up in the config file. If the remote isn't
// found then NotFoundInConfigFile will be returned.
//
// On Windows avoid single character remote names as they can be mixed
// up with drive letters.
func NewFs(path string) (Fs, error) {
fsInfo, configName, fsPath, config, err := ConfigFs(path)
if err != nil {
return nil, err
}
return fsInfo.NewFs(configName, fsPath, config)
}
// TemporaryLocalFs creates a local FS in the OS's temporary directory.
//
// No cleanup is performed, the caller must call Purge on the Fs themselves.
func TemporaryLocalFs() (Fs, error) {
path, err := ioutil.TempDir("", "rclone-spool")
if err == nil {
err = os.Remove(path)
}
if err != nil {
return nil, err
}
path = filepath.ToSlash(path)
return NewFs(path)
}
// CheckClose is a utility function used to check the return from
// Close in a defer statement.
func CheckClose(c io.Closer, err *error) {
cerr := c.Close()
if *err == nil {
*err = cerr
}
}
// FileExists returns true if a file remote exists.
// If remote is a directory, FileExists returns false.
func FileExists(fs Fs, remote string) (bool, error) {
_, err := fs.NewObject(remote)
if err != nil {
if err == ErrorObjectNotFound || err == ErrorNotAFile || err == ErrorPermissionDenied {
return false, nil
}
return false, err
}
return true, nil
}
// GetModifyWindow calculates the maximum modify window between the given Fses
// and the Config.ModifyWindow parameter.
func GetModifyWindow(fss ...Info) time.Duration {
window := Config.ModifyWindow
for _, f := range fss {
if f != nil {
precision := f.Precision()
if precision == ModTimeNotSupported {
return ModTimeNotSupported
}
if precision > window {
window = precision
}
}
}
return window
}