AsyncMirror | BrowserFS

AsyncMirrorFS mirrors a synchronous filesystem into an asynchronous filesystem by:

Performing operations over the in-memory copy, while asynchronously pipelining them to the backing store.
During application loading, the contents of the async file system can be reloaded into the synchronous store, if desired.

The two stores will be kept in sync. The most common use-case is to pair a synchronous in-memory filesystem with an asynchronous backing store.

Example: Mirroring an IndexedDB file system to an in memory file system. Now, you can use IndexedDB synchronously.

new BrowserFS.FileSystem.IndexedDB(function (e, idbfs) {
  var inMemory = new BrowserFS.FileSystem.InMemory();
  var mirrored = new BrowserFS.FileSystem.AsyncMirror(inMemory, idbfs);
  mirrored.initialize(function (e) {
    BrowserFS.initialized(mirrored);
  });
});

Hierarchy

SynchronousFileSystem
- AsyncMirror

Implements

FileSystem

Index

Constructors

constructor

Methods

Constructors

constructor

new AsyncMirror(sync: FileSystem, async: FileSystem): AsyncMirror

- Defined in backend/AsyncMirror.ts:75
Mirrors the synchronous file system into the asynchronous file system.

IMPORTANT: You must call initialize on the file system before it can be used.

Parameters
- sync: FileSystem
  
  The synchronous file system to mirror the asynchronous file system to.
- async: FileSystem
  
  The asynchronous file system to mirror.
Returns AsyncMirror

Methods

_syncSync

_syncSync(fd: PreloadFile<any>): void

- Defined in backend/AsyncMirror.ts:97
Parameters
- fd: PreloadFile<any>
Returns void

appendFile

appendFile(fname: string, data: any, encoding: string | null, flag: FileFlag, mode: number, cb: BFSOneArgCallback): void

Inherited from BaseFileSystem.appendFile
- Defined in core/file_system.ts:689
Parameters
- fname: string
- data: any
- encoding: string | null
- flag: FileFlag
- mode: number
- cb: BFSOneArgCallback
Returns void

appendFileSync

appendFileSync(fname: string, data: any, encoding: string | null, flag: FileFlag, mode: number): void

Inherited from BaseFileSystem.appendFileSync
- Defined in core/file_system.ts:707
Parameters
- fname: string
- data: any
- encoding: string | null
- flag: FileFlag
- mode: number
Returns void

chmod

chmod(p: string, isLchmod: boolean, mode: number, cb: BFSOneArgCallback): void

Implementation of FileSystem.chmod

Inherited from SynchronousFileSystem.chmod

Overrides BaseFileSystem.chmod
- Defined in core/file_system.ts:825
Parameters
- p: string
- isLchmod: boolean
- mode: number
- cb: BFSOneArgCallback
Returns void

chmodSync

chmodSync(p: string, isLchmod: boolean, mode: number): void

Implementation of FileSystem.chmodSync

Overrides BaseFileSystem.chmodSync
- Defined in backend/AsyncMirror.ts:241
Parameters
- p: string
- isLchmod: boolean
- mode: number
Returns void

chown

chown(p: string, isLchown: boolean, uid: number, gid: number, cb: BFSOneArgCallback): void

Implementation of FileSystem.chown

Inherited from SynchronousFileSystem.chown

Overrides BaseFileSystem.chown
- Defined in core/file_system.ts:834
Parameters
- p: string
- isLchown: boolean
- uid: number
- gid: number
- cb: BFSOneArgCallback
Returns void

chownSync

chownSync(p: string, isLchown: boolean, uid: number, gid: number): void

Implementation of FileSystem.chownSync

Overrides BaseFileSystem.chownSync
- Defined in backend/AsyncMirror.ts:250
Parameters
- p: string
- isLchown: boolean
- uid: number
- gid: number
Returns void

createFile

createFile(p: string, flag: FileFlag, mode: number, cb: BFSCallback): void

Inherited from BaseFileSystem.createFile
- Defined in core/file_system.ts:366
Create the file at path p with the given mode. Then, open it with the given flag.

Parameters
- p: string
- flag: FileFlag
- mode: number
- cb: BFSCallback
Returns void

createFileSync

createFileSync(p: string, flag: FileFlag, mode: number): File

Inherited from BaseFileSystem.createFileSync
- Defined in core/file_system.ts:450
Create the file at path p with the given mode. Then, open it with the given flag.

Parameters
- p: string
- flag: FileFlag
- mode: number
Returns File

diskSpace

diskSpace(p: string, cb: function): void

Inherited from BaseFileSystem.diskSpace
- Defined in core/file_system.ts:351
Parameters
- p: string
- cb: function
  - - (total: number, free: number): any
    - Parameters
      - total: number
      - free: number
      Returns any
Returns void

exists

exists(p: string, cb: function): void

Inherited from BaseFileSystem.exists
- Defined in core/file_system.ts:520
Parameters
- p: string
- cb: function
  - - (exists: boolean): void
    - Parameters
      - exists: boolean
      Returns void
Returns void

existsSync

existsSync(p: string): boolean

Implementation of FileSystem.existsSync

Overrides BaseFileSystem.existsSync
- Defined in backend/AsyncMirror.ts:236
Parameters
- p: string
Returns boolean

getName

getName(): string

Implementation of FileSystem.getName
- Defined in backend/AsyncMirror.ts:93
Returns string

initialize

initialize(userCb: BFSOneArgCallback): void

- Defined in backend/AsyncMirror.ts:108
Called once to load up files from async storage into sync storage.

Parameters
- userCb: BFSOneArgCallback
Returns void

isReadOnly

isReadOnly(): boolean

Implementation of FileSystem.isReadOnly
- Defined in backend/AsyncMirror.ts:177
Returns boolean

link

link(srcpath: string, dstpath: string, cb: BFSOneArgCallback): void

Implementation of FileSystem.link

Inherited from SynchronousFileSystem.link

Overrides BaseFileSystem.link
- Defined in core/file_system.ts:852
Parameters
- srcpath: string
- dstpath: string
- cb: BFSOneArgCallback
Returns void

linkSync

linkSync(srcpath: string, dstpath: string): void

Implementation of FileSystem.linkSync

Inherited from BaseFileSystem.linkSync
- Defined in core/file_system.ts:739
Parameters
- srcpath: string
- dstpath: string
Returns void

mkdir

mkdir(p: string, mode: number, cb: BFSOneArgCallback): void

Implementation of FileSystem.mkdir

Inherited from SynchronousFileSystem.mkdir

Overrides BaseFileSystem.mkdir
- Defined in core/file_system.ts:808
Parameters
- p: string
- mode: number
- cb: BFSOneArgCallback
Returns void

mkdirSync

mkdirSync(p: string, mode: number): void

Implementation of FileSystem.mkdirSync

Overrides BaseFileSystem.mkdirSync
- Defined in backend/AsyncMirror.ts:222
Parameters
- p: string
- mode: number
Returns void

open

open(p: string, flags: FileFlag, mode: number, cb: BFSCallback): void

Implementation of FileSystem.open

Inherited from SynchronousFileSystem.open

Overrides BaseFileSystem.open
- Defined in core/file_system.ts:782
Parameters
- p: string
- flags: FileFlag
- mode: number
- cb: BFSCallback
Returns void

openFile

openFile(p: string, flag: FileFlag, cb: BFSCallback): void

Inherited from BaseFileSystem.openFile
- Defined in core/file_system.ts:359
Opens the file at path p with the given flag. The file must exist.

Parameters
- p: string
  
  The path to open.
- flag: FileFlag
  
  The flag to use when opening the file.
- cb: BFSCallback
Returns void

openFileSync

openFileSync(p: string, flag: FileFlag, mode: number): File

Inherited from BaseFileSystem.openFileSync
- Defined in core/file_system.ts:443
Opens the file at path p with the given flag. The file must exist.

Parameters
- p: string
  
  The path to open.
- flag: FileFlag
  
  The flag to use when opening the file.
- mode: number
Returns File

A File object corresponding to the opened file.

openSync

openSync(p: string, flag: FileFlag, mode: number): File

Implementation of FileSystem.openSync

Overrides BaseFileSystem.openSync
- Defined in backend/AsyncMirror.ts:196
Parameters
- p: string
- flag: FileFlag
- mode: number
Returns File

readFile

readFile(fname: string, encoding: string | null, flag: FileFlag, cb: BFSCallback): void

Implementation of FileSystem.readFile

Inherited from BaseFileSystem.readFile
- Defined in core/file_system.ts:597
Parameters
- fname: string
- encoding: string | null
- flag: FileFlag
- cb: BFSCallback
Returns void

readFileSync

readFileSync(fname: string, encoding: string | null, flag: FileFlag): any

Implementation of FileSystem.readFileSync

Inherited from BaseFileSystem.readFileSync
- Defined in core/file_system.ts:634
Parameters
- fname: string
- encoding: string | null
- flag: FileFlag
Returns any

readdir

readdir(p: string, cb: BFSCallback): void

Implementation of FileSystem.readdir

Inherited from SynchronousFileSystem.readdir

Overrides BaseFileSystem.readdir
- Defined in core/file_system.ts:817
Parameters
- p: string
- cb: BFSCallback
Returns void

readdirSync

readdirSync(p: string): string[]

Implementation of FileSystem.readdirSync

Overrides BaseFileSystem.readdirSync
- Defined in backend/AsyncMirror.ts:231
Parameters
- p: string
Returns string[]

readlink

readlink(p: string, cb: BFSCallback): void

Implementation of FileSystem.readlink

Inherited from SynchronousFileSystem.readlink

Overrides BaseFileSystem.readlink
- Defined in core/file_system.ts:870
Parameters
- p: string
- cb: BFSCallback
Returns void

readlinkSync

readlinkSync(p: string): string

Implementation of FileSystem.readlinkSync

Inherited from BaseFileSystem.readlinkSync
- Defined in core/file_system.ts:751
Parameters
- p: string
Returns string

realpath

realpath(p: string, cache: object, cb: BFSCallback): void

Inherited from BaseFileSystem.realpath
- Defined in core/file_system.ts:533
Parameters
- p: string
- cache: object
  - [path: string]: string
- cb: BFSCallback
Returns void

realpathSync

realpathSync(p: string, cache: object): string

Inherited from BaseFileSystem.realpathSync
- Defined in core/file_system.ts:554
Parameters
- p: string
- cache: object
  - [path: string]: string
Returns string

rename

rename(oldPath: string, newPath: string, cb: BFSOneArgCallback): void

Implementation of FileSystem.rename

Inherited from SynchronousFileSystem.rename

Overrides BaseFileSystem.rename
- Defined in core/file_system.ts:765
Parameters
- oldPath: string
- newPath: string
- cb: BFSOneArgCallback
Returns void

renameSync

renameSync(oldPath: string, newPath: string): void

Implementation of FileSystem.renameSync

Overrides BaseFileSystem.renameSync
- Defined in backend/AsyncMirror.ts:182
Parameters
- oldPath: string
- newPath: string
Returns void

rmdir

rmdir(p: string, cb: BFSOneArgCallback): void

Implementation of FileSystem.rmdir

Inherited from SynchronousFileSystem.rmdir

Overrides BaseFileSystem.rmdir
- Defined in core/file_system.ts:799
Parameters
- p: string
- cb: BFSOneArgCallback
Returns void

rmdirSync

rmdirSync(p: string): void

Implementation of FileSystem.rmdirSync

Overrides BaseFileSystem.rmdirSync
- Defined in backend/AsyncMirror.ts:213
Parameters
- p: string
Returns void

stat

stat(p: string, isLstat: boolean | null, cb: BFSCallback): void

Implementation of FileSystem.stat

Inherited from SynchronousFileSystem.stat

Overrides BaseFileSystem.stat
- Defined in core/file_system.ts:774
Parameters
- p: string
- isLstat: boolean | null
- cb: BFSCallback
Returns void

statSync

statSync(p: string, isLstat: boolean): Stats

Overrides BaseFileSystem.statSync
- Defined in backend/AsyncMirror.ts:191
Parameters
- p: string
- isLstat: boolean
Returns Stats

supportsLinks

supportsLinks(): boolean

Implementation of FileSystem.supportsLinks

Overrides BaseFileSystem.supportsLinks
- Defined in backend/AsyncMirror.ts:179
Returns boolean

supportsProps

supportsProps(): boolean

Implementation of FileSystem.supportsProps
- Defined in backend/AsyncMirror.ts:180
Returns boolean

supportsSynch

supportsSynch(): boolean

Implementation of FileSystem.supportsSynch

Overrides SynchronousFileSystem.supportsSynch
- Defined in backend/AsyncMirror.ts:178
Returns boolean

symlink

symlink(srcpath: string, dstpath: string, type: string, cb: BFSOneArgCallback): void

Implementation of FileSystem.symlink

Inherited from SynchronousFileSystem.symlink

Overrides BaseFileSystem.symlink
- Defined in core/file_system.ts:861
Parameters
- srcpath: string
- dstpath: string
- type: string
- cb: BFSOneArgCallback
Returns void

symlinkSync

symlinkSync(srcpath: string, dstpath: string, type: string): void

Implementation of FileSystem.symlinkSync

Inherited from BaseFileSystem.symlinkSync
- Defined in core/file_system.ts:745
Parameters
- srcpath: string
- dstpath: string
- type: string
Returns void

truncate

truncate(p: string, len: number, cb: BFSOneArgCallback): void

Implementation of FileSystem.truncate

Inherited from BaseFileSystem.truncate
- Defined in core/file_system.ts:574
Parameters
- p: string
- len: number
- cb: BFSOneArgCallback
Returns void

truncateSync

truncateSync(p: string, len: number): void

Implementation of FileSystem.truncateSync

Inherited from BaseFileSystem.truncateSync
- Defined in core/file_system.ts:586
Parameters
- p: string
- len: number
Returns void

unlink

unlink(p: string, cb: BFSOneArgCallback): void

Implementation of FileSystem.unlink

Inherited from SynchronousFileSystem.unlink

Overrides BaseFileSystem.unlink
- Defined in core/file_system.ts:790
Parameters
- p: string
- cb: BFSOneArgCallback
Returns void

unlinkSync

unlinkSync(p: string): void

Implementation of FileSystem.unlinkSync

Overrides BaseFileSystem.unlinkSync
- Defined in backend/AsyncMirror.ts:204
Parameters
- p: string
Returns void

utimes

utimes(p: string, atime: Date, mtime: Date, cb: BFSOneArgCallback): void

Implementation of FileSystem.utimes

Inherited from SynchronousFileSystem.utimes

Overrides BaseFileSystem.utimes
- Defined in core/file_system.ts:843
Parameters
- p: string
- atime: Date
- mtime: Date
- cb: BFSOneArgCallback
Returns void

utimesSync

utimesSync(p: string, atime: Date, mtime: Date): void

Implementation of FileSystem.utimesSync

Overrides BaseFileSystem.utimesSync
- Defined in backend/AsyncMirror.ts:259
Parameters
- p: string
- atime: Date
- mtime: Date
Returns void

writeFile

writeFile(fname: string, data: any, encoding: string | null, flag: FileFlag, mode: number, cb: BFSOneArgCallback): void

Implementation of FileSystem.writeFile

Inherited from BaseFileSystem.writeFile
- Defined in core/file_system.ts:651
Parameters
- fname: string
- data: any
- encoding: string | null
- flag: FileFlag
- mode: number
- cb: BFSOneArgCallback
Returns void

writeFileSync

writeFileSync(fname: string, data: any, encoding: string | null, flag: FileFlag, mode: number): void

Inherited from BaseFileSystem.writeFileSync
- Defined in core/file_system.ts:676
Parameters
- fname: string
- data: any
- encoding: string | null
- flag: FileFlag
- mode: number
Returns void

Static isAvailable

isAvailable(): boolean

- Defined in backend/AsyncMirror.ts:63
Returns boolean

Hierarchy

Implements

Index

Constructors

Methods

Constructors

constructor

Parameters

sync: FileSystem

async: FileSystem

Returns AsyncMirror

Methods

_syncSync

Parameters

fd: PreloadFile<any>

Returns void

appendFile

Parameters

fname: string

data: any

encoding: string | null

flag: FileFlag

mode: number

cb: BFSOneArgCallback

Returns void

appendFileSync

Parameters

fname: string

data: any

encoding: string | null

flag: FileFlag

mode: number

Returns void

chmod

Parameters

p: string

isLchmod: boolean

mode: number

cb: BFSOneArgCallback

Returns void

chmodSync

Parameters

p: string

isLchmod: boolean

mode: number

Returns void

chown

Parameters

p: string

isLchown: boolean

uid: number

gid: number

cb: BFSOneArgCallback

Returns void

chownSync

Parameters

p: string

isLchown: boolean

uid: number

gid: number

Returns void

createFile

Parameters

p: string

flag: FileFlag

mode: number

cb: BFSCallback

Returns void

createFileSync

Parameters

p: string

flag: FileFlag

mode: number

Returns File

diskSpace

Parameters

p: string

cb: function

Parameters

total: number