rclone/fs/object/object.go

316 lines
8.2 KiB
Go

// Package object defines some useful Objects
package object
import (
"bytes"
"context"
"errors"
"io"
"time"
"github.com/rclone/rclone/fs"
"github.com/rclone/rclone/fs/hash"
)
// StaticObjectInfo is an ObjectInfo which can be constructed from scratch
type StaticObjectInfo struct {
remote string
modTime time.Time
size int64
storable bool
hashes map[hash.Type]string
fs fs.Info
meta fs.Metadata
mimeType string
}
// NewStaticObjectInfo returns a static ObjectInfo
// If hashes is nil and fs is not nil, the hash map will be replaced with
// empty hashes of the types supported by the fs.
func NewStaticObjectInfo(remote string, modTime time.Time, size int64, storable bool, hashes map[hash.Type]string, f fs.Info) *StaticObjectInfo {
info := &StaticObjectInfo{
remote: remote,
modTime: modTime,
size: size,
storable: storable,
hashes: hashes,
fs: f,
}
if f != nil && hashes == nil {
set := f.Hashes().Array()
info.hashes = make(map[hash.Type]string)
for _, ht := range set {
info.hashes[ht] = ""
}
}
return info
}
// WithMetadata adds meta to the ObjectInfo
func (i *StaticObjectInfo) WithMetadata(meta fs.Metadata) *StaticObjectInfo {
i.meta = meta
return i
}
// WithMimeType adds meta to the ObjectInfo
func (i *StaticObjectInfo) WithMimeType(mimeType string) *StaticObjectInfo {
i.mimeType = mimeType
return i
}
// Fs returns read only access to the Fs that this object is part of
func (i *StaticObjectInfo) Fs() fs.Info {
return i.fs
}
// Remote returns the remote path
func (i *StaticObjectInfo) Remote() string {
return i.remote
}
// String returns a description of the Object
func (i *StaticObjectInfo) String() string {
return i.remote
}
// ModTime returns the modification date of the file
func (i *StaticObjectInfo) ModTime(ctx context.Context) time.Time {
return i.modTime
}
// Size returns the size of the file
func (i *StaticObjectInfo) Size() int64 {
return i.size
}
// Storable says whether this object can be stored
func (i *StaticObjectInfo) Storable() bool {
return i.storable
}
// Hash returns the requested hash of the contents
func (i *StaticObjectInfo) Hash(ctx context.Context, h hash.Type) (string, error) {
if len(i.hashes) == 0 {
return "", hash.ErrUnsupported
}
if hash, ok := i.hashes[h]; ok {
return hash, nil
}
return "", hash.ErrUnsupported
}
// Metadata on the object
func (i *StaticObjectInfo) Metadata(ctx context.Context) (fs.Metadata, error) {
return i.meta, nil
}
// MimeType returns the content type of the Object if
// known, or "" if not
func (i *StaticObjectInfo) MimeType(ctx context.Context) string {
return i.mimeType
}
// Check interfaces
var (
_ fs.ObjectInfo = (*StaticObjectInfo)(nil)
_ fs.Metadataer = (*StaticObjectInfo)(nil)
_ fs.MimeTyper = (*StaticObjectInfo)(nil)
)
// MemoryFs is an in memory Fs, it only supports FsInfo and Put
var MemoryFs memoryFs
// memoryFs is an in memory fs
type memoryFs struct{}
// Name of the remote (as passed into NewFs)
func (memoryFs) Name() string { return "memory" }
// Root of the remote (as passed into NewFs)
func (memoryFs) Root() string { return "" }
// String returns a description of the FS
func (memoryFs) String() string { return "memory" }
// Precision of the ModTimes in this Fs
func (memoryFs) Precision() time.Duration { return time.Nanosecond }
// Returns the supported hash types of the filesystem
func (memoryFs) Hashes() hash.Set { return hash.Supported() }
// Features returns the optional features of this Fs
func (memoryFs) Features() *fs.Features { return &fs.Features{} }
// 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.
func (memoryFs) List(ctx context.Context, dir string) (entries fs.DirEntries, err error) {
return nil, nil
}
// NewObject finds the Object at remote. If it can't be found
// it returns the error ErrorObjectNotFound.
func (memoryFs) NewObject(ctx context.Context, remote string) (fs.Object, error) {
return nil, fs.ErrorObjectNotFound
}
// 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
func (memoryFs) Put(ctx context.Context, in io.Reader, src fs.ObjectInfo, options ...fs.OpenOption) (fs.Object, error) {
o := NewMemoryObject(src.Remote(), src.ModTime(ctx), nil)
return o, o.Update(ctx, in, src, options...)
}
// Mkdir makes the directory (container, bucket)
//
// Shouldn't return an error if it already exists
func (memoryFs) Mkdir(ctx context.Context, dir string) error {
return errors.New("memoryFs: can't make directory")
}
// Rmdir removes the directory (container, bucket) if empty
//
// Return an error if it doesn't exist or isn't empty
func (memoryFs) Rmdir(ctx context.Context, dir string) error {
return fs.ErrorDirNotFound
}
var _ fs.Fs = MemoryFs
// MemoryObject is an in memory object
type MemoryObject struct {
remote string
modTime time.Time
content []byte
meta fs.Metadata
}
// NewMemoryObject returns an in memory Object with the modTime and content passed in
func NewMemoryObject(remote string, modTime time.Time, content []byte) *MemoryObject {
return &MemoryObject{
remote: remote,
modTime: modTime,
content: content,
}
}
// WithMetadata adds meta to the MemoryObject
func (o *MemoryObject) WithMetadata(meta fs.Metadata) *MemoryObject {
o.meta = meta
return o
}
// Content returns the underlying buffer
func (o *MemoryObject) Content() []byte {
return o.content
}
// Fs returns read only access to the Fs that this object is part of
func (o *MemoryObject) Fs() fs.Info {
return MemoryFs
}
// Remote returns the remote path
func (o *MemoryObject) Remote() string {
return o.remote
}
// String returns a description of the Object
func (o *MemoryObject) String() string {
return o.remote
}
// ModTime returns the modification date of the file
func (o *MemoryObject) ModTime(ctx context.Context) time.Time {
return o.modTime
}
// Size returns the size of the file
func (o *MemoryObject) Size() int64 {
return int64(len(o.content))
}
// Storable says whether this object can be stored
func (o *MemoryObject) Storable() bool {
return true
}
// Hash returns the requested hash of the contents
func (o *MemoryObject) Hash(ctx context.Context, h hash.Type) (string, error) {
hash, err := hash.NewMultiHasherTypes(hash.Set(h))
if err != nil {
return "", err
}
_, err = hash.Write(o.content)
if err != nil {
return "", err
}
return hash.Sums()[h], nil
}
// SetModTime sets the metadata on the object to set the modification date
func (o *MemoryObject) SetModTime(ctx context.Context, modTime time.Time) error {
o.modTime = modTime
return nil
}
// Open opens the file for read. Call Close() on the returned io.ReadCloser
func (o *MemoryObject) Open(ctx context.Context, options ...fs.OpenOption) (io.ReadCloser, error) {
content := o.content
for _, option := range options {
switch x := option.(type) {
case *fs.RangeOption:
content = o.content[x.Start:x.End]
case *fs.SeekOption:
content = o.content[x.Offset:]
default:
if option.Mandatory() {
fs.Logf(o, "Unsupported mandatory option: %v", option)
}
}
}
return io.NopCloser(bytes.NewBuffer(content)), nil
}
// Update in to the object with the modTime given of the given size
//
// This re-uses the internal buffer if at all possible.
func (o *MemoryObject) Update(ctx context.Context, in io.Reader, src fs.ObjectInfo, options ...fs.OpenOption) (err error) {
size := src.Size()
if size == 0 {
o.content = nil
} else if size < 0 || int64(cap(o.content)) < size {
o.content, err = io.ReadAll(in)
} else {
o.content = o.content[:size]
_, err = io.ReadFull(in, o.content)
}
o.modTime = src.ModTime(ctx)
return err
}
// Remove this object
func (o *MemoryObject) Remove(ctx context.Context) error {
return errors.New("memoryObject.Remove not supported")
}
// Metadata on the object
func (o *MemoryObject) Metadata(ctx context.Context) (fs.Metadata, error) {
return o.meta, nil
}
// Check interfaces
var (
_ fs.Object = (*MemoryObject)(nil)
_ fs.Metadataer = (*MemoryObject)(nil)
)