fs

Access the file system.

Security

This module prevents path traversal, not allowing parent directory accessors to be used (i.e. “/usr/path/to/../file” or ”../path/to/file” paths are not allowed). Paths accessed with this API must be either relative to one of the base directories or absolute paths. By default Taurify allows full filesystem access, when using the file system module. You can restrict the access to base directories or customized paths by providing Taurify a Tauri capability file.

References

BaseDirectory

Re-exports BaseDirectory

Enumerations

SeekMode

Enumeration Members

Current

Current: 1;

End

End: 2;

Start

Start: 0;

Classes

FileHandle

The Tauri abstraction for reading and writing files.

Extends

• Resource

Constructors

new FileHandle()

new FileHandle(rid): FileHandle

Parameters

Parameter	Type
rid	number

Returns

FileHandle

Inherited from

Resource.constructor

Accessors

rid

Get Signature

get rid(): number

Returns

number

Inherited from

Resource.rid

Methods

close()

close(): Promise<void>

Destroys and cleans up this resource from memory. You should not call any method on this object anymore and should drop any reference to it.

Returns

Promise<void>

Inherited from

Resource.close

read()

read(buffer): Promise<null | number>

Reads up to p.byteLength bytes into p. It resolves to the number of bytes read (0 < n <= p.byteLength) and rejects if any error encountered. Even if read() resolves to n < p.byteLength, it may use all of p as scratch space during the call. If some data is available but not p.byteLength bytes, read() conventionally resolves to what is available instead of waiting for more.

When read() encounters end-of-file condition, it resolves to EOF (null).

When read() encounters an error, it rejects with an error.

Callers should always process the n > 0 bytes returned before considering the EOF (null). Doing so correctly handles I/O errors that happen after reading some bytes and also both of the allowed EOF behaviors.

Parameters

Parameter	Type
buffer	Uint8Array<ArrayBufferLike>

Returns

Promise<null | number>

Example

import { open, BaseDirectory } from "@crabnebula/taurify-api/fs"
// if "$APPCONFIG/foo/bar.txt" contains the text "hello world":
const file = await open("foo/bar.txt", { baseDir: BaseDirectory.AppConfig });
const buf = new Uint8Array(100);
const numberOfBytesRead = await file.read(buf); // 11 bytes
const text = new TextDecoder().decode(buf);  // "hello world"
await file.close();

seek()

seek(offset, whence): Promise<number>

Seek sets the offset for the next read() or write() to offset, interpreted according to whence: Start means relative to the start of the file, Current means relative to the current offset, and End means relative to the end. Seek resolves to the new offset relative to the start of the file.

Seeking to an offset before the start of the file is an error. Seeking to any positive offset is legal, but the behavior of subsequent I/O operations on the underlying object is implementation-dependent. It returns the number of cursor position.

Parameters

Parameter	Type
offset	number
whence	SeekMode

Returns

Promise<number>

Example

import { open, SeekMode, BaseDirectory } from '@crabnebula/taurify-api/fs';

// Given hello.txt pointing to file with "Hello world", which is 11 bytes long:
const file = await open('hello.txt', { read: true, write: true, truncate: true, create: true, baseDir: BaseDirectory.AppLocalData });
await file.write(new TextEncoder().encode("Hello world"));

// Seek 6 bytes from the start of the file
console.log(await file.seek(6, SeekMode.Start)); // "6"
// Seek 2 more bytes from the current position
console.log(await file.seek(2, SeekMode.Current)); // "8"
// Seek backwards 2 bytes from the end of the file
console.log(await file.seek(-2, SeekMode.End)); // "9" (e.g. 11-2)

await file.close();

stat()

stat(): Promise<FileInfo>

Returns a FileInfo for this file.

Returns

Promise<FileInfo>

Example

import { open, BaseDirectory } from '@crabnebula/taurify-api/fs';
const file = await open("file.txt", { read: true, baseDir: BaseDirectory.AppLocalData });
const fileInfo = await file.stat();
console.log(fileInfo.isFile); // true
await file.close();

truncate()

truncate(len?): Promise<void>

Truncates or extends this file, to reach the specified len. If len is not specified then the entire file contents are truncated.

Parameters

Parameter	Type
len?	number

Returns

Promise<void>

Example

import { open, BaseDirectory } from '@crabnebula/taurify-api/fs';

// truncate the entire file
const file = await open("my_file.txt", { read: true, write: true, create: true, baseDir: BaseDirectory.AppLocalData });
await file.truncate();

// truncate part of the file
const file = await open("my_file.txt", { read: true, write: true, create: true, baseDir: BaseDirectory.AppLocalData });
await file.write(new TextEncoder().encode("Hello World"));
await file.truncate(7);
const data = new Uint8Array(32);
await file.read(data);
console.log(new TextDecoder().decode(data)); // Hello W
await file.close();

write()

write(data): Promise<number>

Writes data.byteLength bytes from data to the underlying data stream. It resolves to the number of bytes written from data (0 <= n <= data.byteLength) or reject with the error encountered that caused the write to stop early. write() must reject with a non-null error if would resolve to n < data.byteLength. write() must not modify the slice data, even temporarily.

Parameters

Parameter	Type
data	Uint8Array<ArrayBufferLike>

Returns

Promise<number>

Example

import { open, write, BaseDirectory } from '@crabnebula/taurify-api/fs';
const encoder = new TextEncoder();
const data = encoder.encode("Hello world");
const file = await open("bar.txt", { write: true, baseDir: BaseDirectory.AppLocalData });
const bytesWritten = await file.write(data); // 11
await file.close();

Interfaces

CopyFileOptions

Properties

Property	Type	Description	Defined in
fromPathBaseDir?	BaseDirectory	Base directory for fromPath.
toPathBaseDir?	BaseDirectory	Base directory for toPath.

---

CreateOptions

Properties

Property	Type	Description	Defined in
baseDir?	BaseDirectory	Base directory for path

---

DebouncedWatchOptions

Extends

• WatchOptions

Properties

Property	Type	Description	Inherited from	Defined in
baseDir?	BaseDirectory	Base directory for path	WatchOptions.baseDir
delayMs?	number	Debounce delay	-
recursive?	boolean	Watch a directory recursively	WatchOptions.recursive

---

DirEntry

A disk entry which is either a file, a directory or a symlink.

This is the result of the readDir.

Properties

Property	Type	Description	Defined in
isDirectory	boolean	Specifies whether this entry is a directory or not.
isFile	boolean	Specifies whether this entry is a file or not.
isSymlink	boolean	Specifies whether this entry is a symlink or not.
name	string	The name of the entry (file name with extension or directory name).

---

ExistsOptions

Properties

Property	Type	Description	Defined in
baseDir?	BaseDirectory	Base directory for path.

---

FileInfo

A FileInfo describes a file and is returned by stat, lstat or fstat.

Properties

Property	Type	Description	Defined in
atime	null | Date	The last access time of the file. This corresponds to the atime field from stat on Unix and ftLastAccessTime on Windows. This may not be available on all platforms.
birthtime	null | Date	The creation time of the file. This corresponds to the birthtime field from stat on Mac/BSD and ftCreationTime on Windows. This may not be available on all platforms.
blksize	null | number	Blocksize for filesystem I/O. #### Platform-specific - Windows: Unsupported.
blocks	null | number	Number of blocks allocated to the file, in 512-byte units. #### Platform-specific - Windows: Unsupported.
dev	null | number	ID of the device containing the file. #### Platform-specific - Windows: Unsupported.
fileAttributes	null | number	This field contains the file system attribute information for a file or directory. For possible values and their descriptions, see File Attribute Constants in the Windows Dev Center #### Platform-specific - macOS / Linux / Android / iOS: Unsupported.
gid	null | number	Group ID of the owner of this file. #### Platform-specific - Windows: Unsupported.
ino	null | number	Inode number. #### Platform-specific - Windows: Unsupported.
isDirectory	boolean	True if this is info for a regular directory. Mutually exclusive to FileInfo.isFile and FileInfo.isSymlink.
isFile	boolean	True if this is info for a regular file. Mutually exclusive to FileInfo.isDirectory and FileInfo.isSymlink.
isSymlink	boolean	True if this is info for a symlink. Mutually exclusive to FileInfo.isFile and FileInfo.isDirectory.
mode	null | number	The underlying raw st_mode bits that contain the standard Unix permissions for this file/directory. #### Platform-specific - Windows: Unsupported.
mtime	null | Date	The last modification time of the file. This corresponds to the mtime field from stat on Linux/Mac OS and ftLastWriteTime on Windows. This may not be available on all platforms.
nlink	null | number	Number of hard links pointing to this file. #### Platform-specific - Windows: Unsupported.
rdev	null | number	Device ID of this file. #### Platform-specific - Windows: Unsupported.
readonly	boolean	Whether this is a readonly (unwritable) file.
size	number	The size of the file, in bytes.
uid	null | number	User ID of the owner of this file. #### Platform-specific - Windows: Unsupported.

---

MkdirOptions

Properties

Property	Type	Description	Defined in
baseDir?	BaseDirectory	Base directory for path
mode?	number	Permissions to use when creating the directory (defaults to 0o777, before the process’s umask). Ignored on Windows.
recursive?	boolean	Defaults to false. If set to true, means that any intermediate directories will also be created (as with the shell command mkdir -p).

---

OpenOptions

Properties

Property	Type	Description	Defined in
append?	boolean	Sets the option for the append mode. This option, when true, means that writes will append to a file instead of overwriting previous contents. Note that setting { write: true, append: true } has the same effect as setting only { append: true }.
baseDir?	BaseDirectory	Base directory for path
create?	boolean	Sets the option to allow creating a new file, if one doesn’t already exist at the specified path. Requires write or append access to be used.
createNew?	boolean	Defaults to false. If set to true, no file, directory, or symlink is allowed to exist at the target location. Requires write or append access to be used. When createNew is set to true, create and truncate are ignored.
mode?	number	Permissions to use if creating the file (defaults to 0o666, before the process’s umask). Ignored on Windows.
read?	boolean	Sets the option for read access. This option, when true, means that the file should be read-able if opened.
truncate?	boolean	Sets the option for truncating a previous file. If a file is successfully opened with this option set it will truncate the file to 0 size if it already exists. The file must be opened with write access for truncate to work.
write?	boolean	Sets the option for write access. This option, when true, means that the file should be write-able if opened. If the file already exists, any write calls on it will overwrite its contents, by default without truncating it.

---

ReadDirOptions

Properties

Property	Type	Description	Defined in
baseDir?	BaseDirectory	Base directory for path

---

ReadFileOptions

Properties

Property	Type	Description	Defined in
baseDir?	BaseDirectory	Base directory for path

---

RemoveOptions

Properties

Property	Type	Description	Defined in
baseDir?	BaseDirectory	Base directory for path
recursive?	boolean	Defaults to false. If set to true, path will be removed even if it’s a non-empty directory.

---

RenameOptions

Properties

Property	Type	Description	Defined in
newPathBaseDir?	BaseDirectory	Base directory for newPath.
oldPathBaseDir?	BaseDirectory	Base directory for oldPath.

---

StatOptions

Properties

Property	Type	Description	Defined in
baseDir?	BaseDirectory	Base directory for path.

---

TruncateOptions

Properties

Property	Type	Description	Defined in
baseDir?	BaseDirectory	Base directory for path.

---

WatchEvent

Properties

Property	Type	Defined in
attrs	unknown
paths	string[]
type	WatchEventKind

---

WatchOptions

Extended by

• DebouncedWatchOptions

Properties

Property	Type	Description	Defined in
baseDir?	BaseDirectory	Base directory for path
recursive?	boolean	Watch a directory recursively

---

WriteFileOptions

Properties

Property	Type	Description	Defined in
append?	boolean	Defaults to false. If set to true, will append to a file instead of overwriting previous contents.
baseDir?	BaseDirectory	Base directory for path
create?	boolean	Sets the option to allow creating a new file, if one doesn’t already exist at the specified path (defaults to true).
createNew?	boolean	Sets the option to create a new file, failing if it already exists.
mode?	number	File permissions. Ignored on Windows.

Type Aliases

UnwatchFn()

type UnwatchFn: () => void;

Returns

void

---

WatchEventKind

type WatchEventKind:
  | "any"
  | object
  | object
  | object
  | object
  | "other";

---

WatchEventKindAccess

type WatchEventKindAccess: object | object | object | object;

---

WatchEventKindCreate

type WatchEventKindCreate: object | object | object | object;

---

WatchEventKindModify

type WatchEventKindModify:
  | object
  | object
  | object
  | object
  | object;

---

WatchEventKindRemove

type WatchEventKindRemove: object | object | object | object;

Functions

copyFile()

function copyFile(
   fromPath,
   toPath,
options?): Promise<void>

Copies the contents and permissions of one file to another specified path, by default creating a new file if needed, else overwriting.

Parameters

Parameter	Type
fromPath	string | URL
toPath	string | URL
options?	CopyFileOptions

Returns

Promise<void>

Example

import { copyFile, BaseDirectory } from '@crabnebula/taurify-api/fs';
await copyFile('app.conf', 'app.conf.bk', { fromPathBaseDir: BaseDirectory.AppConfig, toPathBaseDir: BaseDirectory.AppConfig });

---

create()

function create(path, options?): Promise<FileHandle>

Creates a file if none exists or truncates an existing file and resolves to an instance of FileHandle.

Parameters

Parameter	Type
path	string | URL
options?	CreateOptions

Returns

Promise<FileHandle>

Example

import { create, BaseDirectory } from "@crabnebula/taurify-api/fs"
const file = await create("foo/bar.txt", { baseDir: BaseDirectory.AppConfig });
await file.write(new TextEncoder().encode("Hello world"));
await file.close();

---

exists()

function exists(path, options?): Promise<boolean>

Check if a path exists.

Parameters

Parameter	Type
path	string | URL
options?	ExistsOptions

Returns

Promise<boolean>

Example

import { exists, BaseDirectory } from '@crabnebula/taurify-api/fs';
// Check if the `$APPDATA/avatar.png` file exists
await exists('avatar.png', { baseDir: BaseDirectory.AppData });

---

lstat()

function lstat(path, options?): Promise<FileInfo>

Resolves to a FileInfo for the specified path. If path is a symlink, information for the symlink will be returned instead of what it points to.

Parameters

Parameter	Type
path	string | URL
options?	StatOptions

Returns

Promise<FileInfo>

Example

import { lstat, BaseDirectory } from '@crabnebula/taurify-api/fs';
const fileInfo = await lstat("hello.txt", { baseDir: BaseDirectory.AppLocalData });
console.log(fileInfo.isFile); // true

---

mkdir()

function mkdir(path, options?): Promise<void>

Creates a new directory with the specified path.

Parameters

Parameter	Type
path	string | URL
options?	MkdirOptions

Returns

Promise<void>

Example

import { mkdir, BaseDirectory } from '@crabnebula/taurify-api/fs';
await mkdir('users', { baseDir: BaseDirectory.AppLocalData });

---

open()

function open(path, options?): Promise<FileHandle>

Open a file and resolve to an instance of FileHandle. The file does not need to previously exist if using the create or createNew open options. It is the callers responsibility to close the file when finished with it.

Parameters

Parameter	Type
path	string | URL
options?	OpenOptions

Returns

Promise<FileHandle>

Example

import { open, BaseDirectory } from "@crabnebula/taurify-api/fs"
const file = await open("foo/bar.txt", { read: true, write: true, baseDir: BaseDirectory.AppLocalData });
// Do work with file
await file.close();

---

readDir()

function readDir(path, options?): Promise<DirEntry[]>

Reads the directory given by path and returns an array of DirEntry.

Parameters

Parameter	Type
path	string | URL
options?	ReadDirOptions

Returns

Promise<DirEntry[]>

Example

import { readDir, BaseDirectory } from '@crabnebula/taurify-api/fs';
import { join } from '../../path';
const dir = "users"
const entries = await readDir('users', { baseDir: BaseDirectory.AppLocalData });
processEntriesRecursively(dir, entries);
async function processEntriesRecursively(parent, entries) {
  for (const entry of entries) {
    console.log(`Entry: ${entry.name}`);
    if (entry.isDirectory) {
       const dir = await join(parent, entry.name);
      processEntriesRecursively(dir, await readDir(dir, { baseDir: BaseDirectory.AppLocalData }))
    }
  }
}

---

readFile()

function readFile(path, options?): Promise<Uint8Array>

Reads and resolves to the entire contents of a file as an array of bytes. TextDecoder can be used to transform the bytes to string if required.

Parameters

Parameter	Type
path	string | URL
options?	ReadFileOptions

Returns

Promise<Uint8Array>

Example

import { readFile, BaseDirectory } from '@crabnebula/taurify-api/fs';
const contents = await readFile('avatar.png', { baseDir: BaseDirectory.Resource });

---

readTextFile()

function readTextFile(path, options?): Promise<string>

Reads and returns the entire contents of a file as UTF-8 string.

Parameters

Parameter	Type
path	string | URL
options?	ReadFileOptions

Returns

Promise<string>

Example

import { readTextFile, BaseDirectory } from '@crabnebula/taurify-api/fs';
const contents = await readTextFile('app.conf', { baseDir: BaseDirectory.AppConfig });

---

readTextFileLines()

function readTextFileLines(path, options?): Promise<AsyncIterableIterator<string>>

Returns an async AsyncIterableIterator over the lines of a file as UTF-8 string.

Parameters

Parameter	Type
path	string | URL
options?	ReadFileOptions

Returns

Promise<AsyncIterableIterator<string>>

Example

import { readTextFileLines, BaseDirectory } from '@crabnebula/taurify-api/fs';
const lines = await readTextFileLines('app.conf', { baseDir: BaseDirectory.AppConfig });
for await (const line of lines) {
  console.log(line);
}

You could also call AsyncIterableIterator.next to advance the iterator so you can lazily read the next line whenever you want.

---

remove()

function remove(path, options?): Promise<void>

Removes the named file or directory. If the directory is not empty and the recursive option isn’t set to true, the promise will be rejected.

Parameters

Parameter	Type
path	string | URL
options?	RemoveOptions

Returns

Promise<void>

Example

import { remove, BaseDirectory } from '@crabnebula/taurify-api/fs';
await remove('users/file.txt', { baseDir: BaseDirectory.AppLocalData });
await remove('users', { baseDir: BaseDirectory.AppLocalData });

---

rename()

function rename(
   oldPath,
   newPath,
options?): Promise<void>

Renames (moves) oldpath to newpath. Paths may be files or directories. If newpath already exists and is not a directory, rename() replaces it. OS-specific restrictions may apply when oldpath and newpath are in different directories.

On Unix, this operation does not follow symlinks at either path.

Parameters

Parameter	Type
oldPath	string | URL
newPath	string | URL
options?	RenameOptions

Returns

Promise<void>

Example

import { rename, BaseDirectory } from '@crabnebula/taurify-api/fs';
await rename('avatar.png', 'deleted.png', { oldPathBaseDir: BaseDirectory.App, newPathBaseDir: BaseDirectory.AppLocalData });

---

size()

function size(path): Promise<number>

Get the size of a file or directory. For files, the stat functions can be used as well.

If path is a directory, this function will recursively iterate over every file and every directory inside of path and therefore will be very time consuming if used on larger directories.

Parameters

Parameter	Type
path	string | URL

Returns

Promise<number>

Example

import { size, BaseDirectory } from '@crabnebula/taurify-api/fs';
// Get the size of the `$APPDATA/tauri` directory.
const dirSize = await size('tauri', { baseDir: BaseDirectory.AppData });
console.log(dirSize); // 1024

Since

2.1.0

---

stat()

function stat(path, options?): Promise<FileInfo>

Resolves to a FileInfo for the specified path. Will always follow symlinks but will reject if the symlink points to a path outside of the scope.

Parameters

Parameter	Type
path	string | URL
options?	StatOptions

Returns

Promise<FileInfo>

Example

import { stat, BaseDirectory } from '@crabnebula/taurify-api/fs';
const fileInfo = await stat("hello.txt", { baseDir: BaseDirectory.AppLocalData });
console.log(fileInfo.isFile); // true

---

truncate()

function truncate(
   path,
   len?,
options?): Promise<void>

Truncates or extends the specified file, to reach the specified len. If len is 0 or not specified, then the entire file contents are truncated.

Parameters

Parameter	Type
path	string | URL
len?	number
options?	TruncateOptions

Returns

Promise<void>

Example

import { truncate, readTextFile, writeTextFile, BaseDirectory } from '@crabnebula/taurify-api/fs';
// truncate the entire file
await truncate("my_file.txt", 0, { baseDir: BaseDirectory.AppLocalData });

// truncate part of the file
const filePath = "file.txt";
await writeTextFile(filePath, "Hello World", { baseDir: BaseDirectory.AppLocalData });
await truncate(filePath, 7, { baseDir: BaseDirectory.AppLocalData });
const data = await readTextFile(filePath, { baseDir: BaseDirectory.AppLocalData });
console.log(data);  // "Hello W"

---

watch()

function watch(
   paths,
   cb,
options?): Promise<UnwatchFn>

Watch changes (after a delay) on files or directories.

Parameters

Parameter	Type
paths	string | URL | string[] | URL[]
cb	(event) => void
options?	DebouncedWatchOptions

Returns

Promise<UnwatchFn>

---

watchImmediate()

function watchImmediate(
   paths,
   cb,
options?): Promise<UnwatchFn>

Watch changes on files or directories.

Parameters

Parameter	Type
paths	string | URL | string[] | URL[]
cb	(event) => void
options?	WatchOptions

Returns

Promise<UnwatchFn>

---

writeFile()

function writeFile(
   path,
   data,
options?): Promise<void>

Write data to the given path, by default creating a new file if needed, else overwriting.

Parameters

Parameter	Type
path	string | URL
data	Uint8Array<ArrayBufferLike> | ReadableStream<Uint8Array<ArrayBufferLike>>
options?	WriteFileOptions

Returns

Promise<void>

Example

import { writeFile, BaseDirectory } from '@crabnebula/taurify-api/fs';

let encoder = new TextEncoder();
let data = encoder.encode("Hello World");
await writeFile('file.txt', data, { baseDir: BaseDirectory.AppLocalData });

---

writeTextFile()

function writeTextFile(
   path,
   data,
options?): Promise<void>

Writes UTF-8 string data to the given path, by default creating a new file if needed, else overwriting.

Parameters

Parameter	Type
path	string | URL
data	string
options?	WriteFileOptions

Returns

Promise<void>

Example

import { writeTextFile, BaseDirectory } from '@crabnebula/taurify-api/fs';

await writeTextFile('file.txt', "Hello world", { baseDir: BaseDirectory.AppLocalData });