React Native File System
File system access for React Native applications for Android, iOS,
Mac (Catalyst), and Windows platforms. Supports both new
and old RN architectures.
Table of Contents
- Getting Started
- Project History & Roadmap
- Background Downloads Tutorial (iOS)
- Examples
- API Reference
- Constants
- Functions
- appendFile() — Appends content to a file.
- completeHandlerIOS() — For use when using background downloads,
tell iOS you are done handling a completed download.
- copyAssetsFileIOS() — Reads an image file from Camera Roll and
writes it to the specified location. It also can be used to get video
thumbnails.
- copyAssetsVideoIOS() — Copies a video from the assets-library
to the specified destination.
- copyFile() — Copies a file to a new destination.
- copyFileAssets() — (Android only) Copies Android app's asset(s)
to the specified destination.
- copyFileRes() — (Android only) Copies specified resource to
the given destination.
- copyFolder() — (Windows only) Copies a folder to a new location
in a Windows-efficient way.
- downloadFile() — Downloads a file from network.
- exists() — Checks if an item exists at the given path.
- existsAssets() — (Android only) Checks if an item exists at
the given path inside
the Android assets folder.
- existsRes() — (Android only) Checks if the resource exists.
- hash() — Calculates file hash.
- isResumable() — (iOS only) Check if the the download job with this
ID is resumable with resumeDownload().
- getAllExternalFilesDirs() — (Android only) Returns an array with
the absolute paths to application-specific directories on all shared /
external storage devices where the application can place persistent files
it owns.
- getFSInfo() — Gets info on the free and total storage space
on the device, and its external storage.
- mkdir() — Creates folder(s) at the given path.
- moveFile() — Moves a file (or a folder with files) to a new location.
- pathForGroup() — (iOS only) Returns the absolute path to
the directory shared for all applications with the same security group
identifier.
- pickFile() — Prompts user to select file(s) with help of
a platform-provided file picker UI.
- read() — Reads a fragment of file content.
- readdir() — Lists the content of a folder (names only).
- readDir() — Lists the content of a folder (with item details).
- readDirAssets() — (Android only) Lists the content of a folder at
the given path inside the Android assets folder.
- readFile() — Reads entire file content.
- readFileAssets() — (Android only) Reads the file at a path in
the Android app's assets folder.
- readFileRes() — (Android only) Reads specified file in
the Android app's resource folder and return its contents.
- resumeDownload() — (iOS only) Resume an interrupted download job.
- scanFile() — (Android-only) Scan the file using
Media Scanner.
- stat() — Returns info on a file system item.
- stopDownload() — Aborts a file download job.
- stopUpload() — (iOS only) Aborts file upload job.
- touch() — Alters creation and modification timestamps of the given file.
- unlink() — Unlinks (removes) a file or directory with files.
and return its contents.
- uploadFiles() — Uploads files to a remote location.
- write() — Writes content to a file at the given random access
position.
- writeFile() — Writes content into a file.
- Types
Getting Started
Just install & use:
$ npm install --save @dr.pogodin/react-native-fs
Note: Windows auto-link command (at least as it was needed for example project to install the lib hosted in the parent folder):
npx react-native autolink-windows --sln "windows\ReactNativeFsExample.sln" --proj "windows\ReactNativeFsExample\ReactNativeFsExample.vcxproj"
Project History & Roadmap
This project is a fork of the upstream react-native-fs library, which has been
abandoned by its owners and maintainers. This forks aims to keep the library on
par with the latest React Native standards, with support of the New Architecture,
backward compatibility with the Old Architecture; and to further develop
the library according to the best industry practices.
To migrate from the legacy react-native-fs install this fork_
npm install --save @dr.pogodin/react-native-fs
then upgrade its imports in the code:
import RNFS from 'react-native-fs';
import * as RNFS from '@dr.pogodin/react-native-fs';
import {
TemporaryDirectoryPath,
writeFile,
} from '@dr.pogodin/react-native-fs';
ROADMAP:
-
v2.22.0 of this library is, presumably, a drop-in replacement for
the latest (v2.20.0) release of the original, upstream react-native-fs
(beside the need to upgrade host project to the lates RN v0.73).
It has matching functionality and API, with just a handfull of internal
fixes, and a few additions.
-
In further versions, v2.X.Y, we'll be taking care of improvements,
and optimizations of existing functionality, as well as adding new APIs,
and deprecating old ones (without yet dropping them out of the codebase),
with the ultimate goal to release v3 version of the library.
-
The aims for v3 release are the following:
- To unify library APIs for all platforms — the current library has
a lots of platform-dependent APIs, which goes against the purpose and spirit
of React Native — we'll abstract out and unify everything that is
possible, to allow smooth cross-plaform ride.
- To make library API closer to Node's File System API.
- To ensure that library has no intrinsic limitations (like now it is not efficient
for handling large files, etc.)
Background Downloads Tutorial (iOS)
Background downloads in iOS require a bit of a setup.
First, in your AppDelegate.m
file add the following:
#import <RNFSBackgroundDownloads.h>
...
- (void)application:(UIApplication *)application
handleEventsForBackgroundURLSession:(NSString *)identifier
completionHandler:(void (^)())completionHandler
{
[RNFSBackgroundDownloads
setCompletionHandlerForIdentifier:identifier
completionHandler:completionHandler];
}
The handleEventsForBackgroundURLSession
method is called when a background download is done and your app is not in the foreground.
We need to pass the completionHandler
to RNFS along with its identifier
.
The JavaScript will continue to work as usual when the download is done but now you must call RNFS.completeHandlerIOS(jobId)
when you're done handling the download (show a notification etc.)
BE AWARE! iOS will give about 30 sec. to run your code after handleEventsForBackgroundURLSession
is called and until completionHandler
is triggered so don't do anything that might take a long time (like unzipping), you will be able to do it after the user re-launces the app,
otherwide iOS will terminate your app.
Examples
These are legacy examples, and should be revised, there is an Example app in the /example
folder of the codebase, you probably should rather check it than these examples.
Basic
var RNFS = require('react-native-fs');
RNFS.readDir(RNFS.MainBundlePath)
.then((result) => {
console.log('GOT RESULT', result);
return Promise.all([RNFS.stat(result[0].path), result[0].path]);
})
.then((statResult) => {
if (statResult[0].isFile()) {
return RNFS.readFile(statResult[1], 'utf8');
}
return 'no file';
})
.then((contents) => {
console.log(contents);
})
.catch((err) => {
console.log(err.message, err.code);
});
File creation
var RNFS = require('react-native-fs');
var path = RNFS.DocumentDirectoryPath + '/test.txt';
RNFS.writeFile(path, 'Lorem ipsum dolor sit amet', 'utf8')
.then((success) => {
console.log('FILE WRITTEN!');
})
.catch((err) => {
console.log(err.message);
});
File deletion
var path = RNFS.DocumentDirectoryPath + '/test.txt';
return RNFS.unlink(path)
.then(() => {
console.log('FILE DELETED');
})
.catch((err) => {
console.log(err.message);
});
File upload (Android and IOS only)
var RNFS = require('react-native-fs');
var uploadUrl = 'http://requestb.in/XXXXXXX';
var files = [
{
name: 'test1',
filename: 'test1.w4a',
filepath: RNFS.DocumentDirectoryPath + '/test1.w4a',
filetype: 'audio/x-m4a'
}, {
name: 'test2',
filename: 'test2.w4a',
filepath: RNFS.DocumentDirectoryPath + '/test2.w4a',
filetype: 'audio/x-m4a'
}
];
var upload
= (response) => {
var jobId = response.jobId;
console.log('UPLOAD HAS BEGUN! JobId: ' + jobId);
};
var uploadProgress = (response) => {
var percentage = Math.floor((response.totalBytesSent/response.totalBytesExpectedToSend) * 100);
console.log('UPLOAD IS ' + percentage + '% DONE!');
};
RNFS.uploadFiles({
toUrl: uploadUrl,
files: files,
method: 'POST',
headers: {
'Accept': 'application/json',
},
fields: {
'hello': 'world',
},
begin: uploadBegin,
progress: uploadProgress
}).promise.then((response) => {
if (response.statusCode == 200) {
console.log('FILES UPLOADED!');
} else {
console.log('SERVER ERROR');
}
})
.catch((err) => {
if(err.description === "cancelled") {
}
console.log(err);
});
API Reference
Constants
CachesDirectoryPath
const CachesDirectoryPath: string;
VERIFIED: Android, iOS, macOS, Windows.
The absolute path to the caches directory.
DocumentDirectoryPath
const DocumentDirectoryPath: string;
VERIFIED: Android, iOS, macOS, Windows.
The absolute path to the document directory.
IMPORTANT: DocumentDirectoryPath
(iOS) will include an ID in the path that changes each build e.g ...Application/BCE32988-4C51-483B-892B-16671E3771C2/Documents
.
Use relative paths and resolve the full path at runtime to avoid files not being found on new builds.
DownloadDirectoryPath
const DownloadDirectoryPath: string;
VERIFIED: Android, Windows. NOT SUPPORTED: iOS, macOS.
The absolute path to the download directory (on android and Windows only).
ExternalCachesDirectoryPath
const ExternalCachesDirectoryPath: string;
VERIFIED: Android, Windows (empty?). NOT SUPPORTED: iOS, macOS.
The absolute path to the external caches directory (android only).
ExternalDirectoryPath
const ExternalDirectoryPath: string;
VERIFIED: Android, iOS (empty?), macOS (empty?), Windows.
The absolute path to the external files, shared directory (android only).
ExternalStorageDirectoryPath
const ExternalStorageDirectoryPath: string;
VERIFIED: Android, iOS (empty?), macOS (empty?), Windows (empty?).
The absolute path to the external storage, shared directory (android only).
BEWARE: When using ExternalStorageDirectoryPath
it's necessary to request permissions (on Android) to read and write on the external storage, here an example: React Native Offical Doc
LibraryDirectoryPath
const LibraryDirectoryPath: string;
VERIFIED: iOS, macOS, Windows (empty?). NOT SUPPORTED: Android.
The absolute path to the NSLibraryDirectory (iOS only).
MainBundlePath
const MainBundlePath: string;
VERIFIED: iOS, macOS, Windows. NOT SUPPORTED: Android.
The absolute path to the main bundle directory (not available on Android).
PicturesDirectoryPath
const PicturesDirectoryPath: string;
VERIFIED: Android, Windows. NOT SUPPORTED: iOS, macOS.
The absolute path to the pictures directory.
RoamingDirectoryPath
const RoamingDirectoryPath: string;
VERIFIED: Windows. NOT SUPPORTED: Android, iOS, macOS.
The absolute path to the roaming directory (Windows only).
TemporaryDirectoryPath
const TemporaryDirectoryPath: string;
VERIFIED: Android, iOS, macOS, Windows.
The absolute path to the temporary directory (falls back to Caching-Directory on
Android).
BEWARE: The trailing slash might be inconsistent in this path! At the very
least, on Android this constant does not have a slash in the end; but on iOS
(new arch) it has it. It is something to unify in future.
Functions
appendFile()
function appendFile(filepath: string, contents: string, encoding?: string): Promise<void>;
VERIFIED: Android, iOS, macOS, Windows.
Appends content to a file.
filepath
— string — File path.contents
— string — The content to add.encoding
— EncodingT — Optional. Encoding.- Resolves once the operation has been completed.
completeHandlerIOS()
function completeHandlerIOS(jobId: number): void;
VERIFIED: well... not really verified, but is callable on iOS.
iOS only. For use when using background downloads, tell iOS you are done
handling a completed download.
Read more about background downloads in the Background Downloads Tutorial (iOS) section.
copyAssetsFileIOS()
function copyAssetsFileIOS(
imageUri: string,
destPath: string,
width: number,
height: number,
scale?: number,
compression?: number,
resizeMode?: string,
): Promise<string>;
BEWARE: After ensuring this method gets called correctly on iOS, calling it
just crashes the example app for me. Though, I don't have much interest to dig into
it now (not for free :)
iOS only.
Not available on Mac Catalyst.
Reads an image file from Camera Roll and writes to destPath
. This method
assumes the image file to be JPEG file.
This method will download the original from iCloud if necessary.
One can use this method also to create a thumbNail from a video in a specific
size. Currently it is impossible to specify a concrete position, the OS will
decide which Thumbnail you'll get then.
To copy a video from assets-library and save it as a mp4-file, refer to
copyAssetsVideoIOS.
Further information: https://developer.apple.com/reference/photos/phimagemanager/1616964-requestimageforasset
The promise will on success return the final destination of the file, as it was defined in the destPath-parameter.
-
imageUri
— string — URI of a file in Camera Roll.
Can be either of the following formats:
ph://CC95F08C-88C3-4012-9D6D-64A413D254B3/L0/001
assets-library://asset/asset.JPG?id=CC95F08C-88C3-4012-9D6D-64A413D254B3&ext=JPG
-
destPath
— string — Destination to which the copied file
will be saved, e.g. RNFS.TemporaryDirectoryPath + 'example.jpg'
.
-
width
— number — Copied file's image width will be resized
to width
. If 0 is provided, width won't be resized.
-
height
— number — Copied file's image height will be resized
to height
. If 0 is provided, height won't be resized.
-
scale
— number | undefined — Optional. Copied file's
image will be scaled proportional to scale
factor from width
x height
.
If both width
and height
are 0, the image won't scale. Range is [0.0, 1.0]
and default is 1.0.
-
compression
— number | undefined — Optional. Quality of
copied file's image. The value 0.0 represents the maximum compression
(or lowest quality) while the value 1.0 represents the least compression
(or best quality). Range is [0.0, 1.0] and default is 1.0.
-
resizeMode
— string | undefined — Optional.
If resizeMode
is 'contain', copied file's image will be scaled so that its
larger dimension fits width
x height
. If resizeMode
is other value than
'contain', the image will be scaled so that it completely fills
width
x height
. Default is 'contain'.
Refer to PHImageContentMode.
-
Resolves to string — Copied file's URI.
copyAssetsVideoIOS()
function copyAssetsVideoIOS(videoUri: string, destPath: string): Promise<string>;
BEWARE: Similarly to copyAssetsFileIOS() I believe it gets correctly called
on iOS, but it crashes the example app in my naive test. Perhaps I use it wrong,
or something should be patched in the original implementation.
Not available on Mac Catalyst.
Copies a video from assets-library, that is prefixed with
'assets-library://asset/asset.MOV?...' to a specific destination.
videoUri
— string — Video URI.destPath
— string — Destination.- Resolves to string — copied file path?
copyFile()
function copyFile(from: string, into: string, options?: FileOptionsT): Promise<void>;
VERIFIED: Android, iOS, macOS, Windows.
Copies a file to a new destination. Throws if called on a directory.
Note: On Android and Windows copyFile() will overwrite destPath
if it
already exists. On iOS an error will be thrown if the file already exists.
— beware, this has not been verified yet.
BEWARE: On Android copyFile() throws if called on a folder; on other
platforms it does not throw, but it has not been verified yet, if it actually
copies a folder with all its content there.
from
— string — Source path.into
— string — Destination path.options
— FileOptionsT | undefined — Optional. Additional
settings. beware, it has not been verified they work, yet.- Resolves once done.
copyFileAssets()
function copyFileAssets(from: string, into: string): Promise<void>
VERIFIED: Android. NOT SUPPORTED: iOS, macOS, Windows.
Copies Android app's asset(s) to the specified destination.
If from
points to a file, this function assumes into
is a file path as well,
and it copies the asset to that destination, overwriting the existing file at
that destination, if any.
If from
points to a folder, this function assumes into
is a folder path
as well, and it recursively copies the content of from
into that destination,
preserving the folder structure of copied assets, and overwriting existing files
in the destination in case of conflicts. It does not clean the destination prior
to copying into it, and it cannot overwrite files by folders and vice-versa.
If into
does not exist, it will be created, assuming its parent folder
does exist (i.e. it does not attempt to create entire path as mkdir() does).
-
from
— string — Source path, relative to the root assets
folder. Can be empty to refer the root assets folder itself.
-
into
— string — Destination path.
-
Resolves once completed.
copyFileRes()
function copyFileRes(filename: string, destPath: string): Promise<void>
VERIFIED: Android. NOT SUPPORTED: iOS, macOS, Windows.
Android-only. Copies the file named filename
in the Android app's res folder
and copies it to the given destPath
path. res/drawable
is used as
the source parent folder for image files, res/raw
for everything else.
BEWARE: It will overwrite destPath if it already exists.
filename
— string — Resource name.destPath
— string — Destination.- Resolves once completed.
copyFolder()
copyFolder(from: string, into: string): Promise<void>;
VERIFIED: Windows NOT SUPPORTED: Android, iOS, macOS
Windows only. Copies content to a new location in a Windows-efficient way,
compared to copyFile().
from
— string — Source location.into
— string — Destination location.
downloadFile()
function downloadFile(options: DownloadFileOptionsT): {
jobId: number;
promise: Promise<DownloadResultT>;
};
VERIFIED: Android, iOS, macOS, Windows
BEWARE: Only basic functionality has been verified.
Downloads a file from options.fromUrl
to options.toFile
. It Will overwrite
any previously existing file.
options
— DownloadFileOptionsT — Download settings.- Returns an object holding
jobId
number (can be used to manage in-progress
download by corresponding functions) and promise
resolving to DownloadResultT
once the download is completed.
exists()
function exists(path: string): Promise<boolean>;
VERIFIED: Android, iOS, macOS, Windows.
Checks if an item exists at the given path
.
path
— string — Path.- Resolves to true if the item exists; to false otherwise.
existsAssets()
function existsAssets(path: string): Promise<boolean>;
VERIFIED: Android. NOT SUPPORTED: iOS, macOS, Windows.
Android-only. Checks if an item exists at the given path in the Android assets
folder.
path
— string — Path, relative to the root of the Android
assets folder.- Resolves true if the item exists; false otherwise.
existsRes()
function existsRes(filename: string): Promise<boolean>;
VERIFIED: Android. NOT SUPPORTED: iOS, macOS, Windows.
Android-only. Check if the specified resource exists.
res/drawable
is used as the parent folder for image files,
res/raw
for everything else.
filename
— string — Resource name.- Resolves to boolean — true if the resource exists;
false otherwise.
getAllExternalFilesDirs()
function getAllExternalFilesDirs(): Promise<string[]>;
VERIFIED: Android. NOT SUPPORTED: iOS, macOS, Windows.
Android-only. Returns an array with the absolute paths to application-specific
directories on all shared/external storage devices where the application can
place persistent files it owns.
- Resolves to string[] — the array of external paths.
getFSInfo()
function getFSInfo(): Promise<FSInfoResultT>;
VERIFIED: Android, iOS, macOS, Windows.
Provides information about free and total file system space.
hash()
function hash(path: string, algorithm: string): Promise<string>;
VERIFIED: Android, iOS, macOS, Windows.
Calculates file's hash.
path
— string — File path.algorithm
— string — One of md5
, sha1
,
sha224
(currently it does not work on Windows!),
sha256
, sha384
, sha512
.- Resolves to string — file hash.
isResumable()
function isResumable(jobId: number): Promise<bool>;
iOS only. Check if the the download job with this ID is resumable with
resumeDownload().
Example:
if (await RNFS.isResumable(jobId) {
RNFS.resumeDownload(jobId)
}
jobId
— number — Download job ID.- Resolves to boolean — the result.
mkdir()
function mkdir(path: string, options?: MkdirOptionsT): Promise<void>;
VERIFIED: Android, iOS, macOS, Windows.
Creates folder(s) at path
, and does not throw if already exists (similar to
mkdir -p
in Linux).
path
— string — Path to create.options
— MkdirOptionsT | undefined — Optional.
Additional parameters.- Resolves once completed.
moveFile()
function moveFile(from: string, into: string): Promise<void>;
VERIFIED: Android, iOS, macOS, Windows.
Moves an item (a file, or a folder with files) to a new location. This is more
performant than reading and then re-writing the file data because the move
is done natively and the data doesn't have to be copied or cross the bridge.
Note: Overwrites existing file in Windows — To be verified, how does
it behave on other systems, and whether it really overwrites items on Windows?
BEWARE: On Windows it currently does not allow moving folders with files,
on other platforms it works fine.
from
— string — Old path of the item.into
— string — New path of the item.- Resolves once the operation is completed.
pathForGroup()
function pathForGroup(groupIdentifier: string): Promise<string>;
VERIFIED: iOS.
iOS only. Returns the absolute path to the directory shared for all applications
with the same security group identifier. This directory can be used to to share
files between application of the same developer.
Invalid group identifier will cause a rejection.
For more information read the Adding an App to an App Group section.
groupIdentifier
— string — Any value from
the com.apple.security.application-groups entitlements list.- Resolves to string — the result path.
pickFile()
function pickFile(options?: PickFileOptionsT): Promise<string[]>;
SUPPORTED: Android, iOS, macOS. NOT YET SUPPORTED: Windows.
Prompts the user to select file(s) using a platform-provided file picker UI,
which also allows to access files outside the app sandbox.
BEWARE: On macOS (Catalyst) for this function to work you MUST go to
Signing & Capabilities settings of your project, and inside its App Sandbox
section to set File Access > User Selected Files to Read/Write value
(with just Read the file picker on macOS opens and seemingly works,
but rather than returning the picked up URL, it signals the operation has been
cancelled).
If it is left at the default None value the call to pickFile() will
crash the app.
-
options
— PickFileOptionsT — Optional parameters. By default,
this function allows user to select a single file of any kind.
-
Resolves to a string array — URIs (paths) of user-selected files,
allowing a direct access to them with other methods in this library
(e.g. readFile()), even if the file is outside the app sandbox.
NOTE: On iOS & macOS it resolve to special values with the format
«bookmark://<BASE64_ENCODED_STRING>
», rather than normal URIs.
It is necessary for the support of security scopes
(see Bookmarks and Security Scopes) in library methods. The «<BASE64_ENCODED_STRING>
»
in this case is a Base64-encoded binary representation of the URL bookmark,
along with its security scope data. Other methods of the library are expected
to automatically handle such special URIs as needed.
BEWARE: It has not been thoroughly verified yet that all library methods
support these «Bookmark URLs» correctly. The expected error in
such case is a failure to access the URLs as non-existing.
read()
function read(path: string, length = 0, position = 0, encodingOrOptions?: EncodingT | ReadFileOptionsT): Promise<string>;
VERIFIED: Android, iOS, macOS, Windows.
Reads length
bytes from the given position
of a file.
BEWARE: On Android and Windows read() called with zero length
and position
resolves to empty string; however on other platforms it resolves to the entire
file content (same as readFile()). This behavior has been inherited from
the legacy RNFS implementation, and is to be corrected in future.
Note: To read entire file at once consider to use readFile() instead.
Note: No matter the encoding, this function will always read the specified
number of bytes from the given position, and then transform that byte chunk
into a string using the given encoding; that is in constrast of, say, reading
the given number of characters, if utf8
is given.
path
— string — File path.length
— number | undefined — Optional. The number of
bytes to read. Defaults 0.position
— number | undefined — Optional. The starting
read position, in bytes. Defaults 0.encodingOrOptions
— EncodingT | ReadFileOptionsT | undefined
— Optional. The encoding to use, or additional read options (currently,
the encoding is the only option anyway). Defaults utf8
.- Resolves to string — the content read from file, transformed into
the string according to the specified encoding.
readdir()
function readdir(path: string): Promise<string[]>;
VERIFIED: Android, iOS, macOS.
Lists the content of given folder (names only — NodeJS-style). Note the
lowercase d
in the name, unlike in readDir().
BEWARE: There is no guarantees about the sort order of resolved listing.
path
— string — Folder path.- Resolves to a string array — the names of items in the folder.
readDir()
function readDir(path: string): Promise<ReadDirItem[]>;
VERIFIED: Android, iOS, macOS, Windows.
Lists the content of given absolute path.
BEWARE: There is no guarantees about the sort order of resolved listing.
BEWARE: On Windows the isDirectory()
and isFile()
methods of result
currently return false for all items; also size
value in the result is
platform dependent for directories.
readDirAssets()
function readDirAssets(path: string): Promise<ReadDirItem[]>;
VERIFIED: Android. NOT SUPPORTED: iOS, macOS, Windows.
(Android only) Lists the content of a folder at the given path
inside
the Android assets folder.
path
— string — Folder path, relative to the root of
the assets
folder.- Resolves to an array of ReadDirAssetsResItemT objects.
readFile()
function readFile(path: string, encodingOrOptions?: EncodingT | ReadFileOptionsT): Promise<string>;
VERIFIED: Android, iOS, macOS, Windows.
Reads the file at path
and return its content as a string.
Note: To read a selected fragment of the file see read().
Note: For base64
encoding this function will return file content encoded
into Base64 format; for ascii
it will fill each character of the result string
with the code of corresponding byte in the file; and for utf8
(default)
it will assume the source file is UTF8-encoded, and it will decode it into
the result string (thus each result character will be corresponding to a group
of 1-to-4 bytes of the source file).
BEWARE: You will take quite a performance hit if you are reading big files.
path
— string — File path.encoding
— EncodingT | ReadFileOptionsT — Optional.
File encoding, or extra options.- Resolves to string — the content read from the file, and transformed
according to the given encoding.
readFileAssets()
function readFileAssets(path: string, encoding?: EncodingT | ReadFileOptionsT): Promise<string>;
VERIFIED: Android. NOT SUPPORTED: iOS, macOS, Windows.
Android-only. Reads the file at path
in the Android app's assets folder
and return its contents. encoding
can be one of utf8
(default), ascii
,
base64
. Use base64
for reading binary files.
path
— string — Asset path.encoding
— EncodingT | ReadFileOptionsT | undefined —
Optional. Encoding, or extra options object, which currently only supports
specifying the encoding.- Resolves to string — the asset content.
readFileRes
function readFileRes(filename: string, encoding?: EncodingT): Promise<string>;
VERIFIED: Android. NOT SUPPORTED: iOS, macOS, Windows.
Android-only. Reads the file named filename
in the Android app's res
folder
and return contents. Only the file name (not folder) needs to be specified.
Original docs say: The file type will be detected from the extension and
automatically located within res/drawable
(for image files) or res/raw
(for everything else). Good luck with it. The test in the example app does not
work if the file extension is not included into the filename... but perhaps
I've overlooked something.
filename
— string — Resouce file name.encoding
— EncodingT — Optional Encdoing.- Resolves to string — the resource content.
resumeDownload()
function resumeDownload(jobId: number): void;
iOS only. Resume the current download job with this ID.
jobId
— number — Download job ID.
scanFile()
function scanFile(path: string): Promise<string | null>;
VERIFIED: Android. NOT SUPPORTED: iOS, macOS, Windows.
Android-only. Scan the file using
Media Scanner.
path
— string — Path of the file to scan.- Resolve to string or null — URI of for the file if the scanning
operation succeeded and the file was added to the media database; or null
if scanning failed.
stat()
function stat(path: string): Promise<StatResultT>;
VERIFIED: Android, iOS, macOS, Windows.
Stats an item at path
. If the path
is linked to a virtual file, for example
Android Content URI, the originalPath
can be used to find the pointed file
path (beware — this has not been verified yet).
BEWARE: On Windows a bunch of stuff in the response is currently not compatible
with the specs — size
is a string rather than number, isDirectory()
and isFile()
do not work (always return false), etc. Also on Windows, even with those defects
accounted for the test for this function tends to randomly fail on a regular basis.
It thus requires more troubleshooting, but it is not a priority for now.
path
— string — Item path.- Resolves to a StatResultT object.
stopDownload()
function stopDownload(jobId: number): void;
VERIFIED: Android, iOS.
Aborts a file download job. The partial file will remain on the filesystem,
and the promise returned from the aborted downloadFile() call will reject
with an error.
stopUpload()
function stopUpload(jobId: number): void;
VERIFIED: iOS.
iOS only. Abort the current upload job with given ID.
NOTE: Unlike stopDownload() it does not cause the pending upload promise
to reject. Perhaps, we'll change it in future to behave similarly.
jobId
— number — Upload job ID.
touch()
function touch(filepath: string, mtime?: Date, ctime?: Date): Promise<void>;
VERIFIED: Android, iOS, macOS, Windows.
Alters creation and modification timestamps of the given file.
filepath
— string — File path.mtime
— Date | undefined — Optional. Modification
timestamp.ctime
— Date | undefined — Optional. Creation timestamp.
It is supported on iOS and Windows; Android always sets both timestamps equal
mtime
.- Resolves once done.
unlink()
function unlink(path: string): Promise<void>;
VERIFIED: Android, iOS, macOS, Windows.
Unlinks (removes) the item at path
. If the item does not exist, an error will
be thrown. Also recursively deletes directories (works like Linux rm -rf
).
path
— string — Item path.- Resolves once done.
uploadFiles()
function uploadFiles(options: UploadFileOptionsT): {
jobId: number;
promise: Promise<UploadResultT>;
}
VERIFIED: Android, iOS, macOS, Windows
Uploads files to a remote location.
BEWARE: Only the most basic upload functionality has been tested so far
in this library fork.
-
options
— UploadFileOptionsT — Upload settings.
-
Returns an object holding jobId
number (can be used to manage
in-progress download by corresponding functions) and promise
resolving
to UploadResultT once the download is completed.
write()
function write(filepath: string, contents: string, position?: number, encoding?: EncodingT): Promise<void>;
VERIFIED: Android, iOS, macOS, Windows
BEWARE: On Windows it seems to work differently from other platforms,
throwing if attempting to write to a non-existing file.
Writes content to a file at the given random access position.
filepath
— string — File path.contents
— string — Content to write.position
— number | undefined — Write position.
If undefined
or -1
the contents is appended to the end of the file.encoding
— EncodingT — Write encoding.- Resolves once the operation has been completed.
writeFile()
function writeFile(path: string, content: string, encodingOrOptions?: EncodingT | WriteFileOptionsT): Promise<void>
VERIFIED: Android, iOS, macOS, Windows.
Write the content
to the file at path
, overwritting it if exists already.
NOTE: With base64
encoding value this function will assume that given
content
is Base64-encoded already, and it will be decoded into the file;
for ascii
encoding each character of content
will be written to one byte
in the file, and the function will fail if any character is outside
the U+0000 to U+00FF range (keep in mind, that regular JS strings have
two-byte characters); and for utf8
encoding (default) it will encode
content
characters (which can be from U+0000 to U+FFFF in this case)
into the corresponding UTF8 code (i.e. each source character will be
turned into a group of 1-to-4 bytes in the written file).
path
— string — File path.content
— string — Data to write into the file.encodingOrOptions
— EncodingT | WriteFileOptionsT — Data
encoding, or extra options.- Resolves once completed.
Types
DownloadBeginCallbackResultT
type DownloadBeginCallbackResultT = {
jobId: number;
statusCode: number;
contentLength: number;
headers: Headers;
};
The type of argument passed to begin
callback in DownloadFileOptionsT.
jobId
— number — The download job ID, required if one wishes
to cancel the download. See stopDownload().statusCode
— number — The HTTP status code.contentLength
— number — The total size in bytes of
the download resource.headers
— StringMapT — The HTTP response headers from
the server.
DownloadFileOptionsT
type DownloadFileOptions = {
fromUrl: string;
toFile: string;
headers?: StringMapT;
background?: boolean;
discretionary?: boolean;
cacheable?: boolean;
progressInterval?: number;
progressDivider?: number;
begin?: (res: DownloadBeginCallbackResultT) => void;
progress?: (res: DownloadProgressCallbackResultT) => void;
resumable?: () => void;
connectionTimeout?: number;
readTimeout?: number;
backgroundTimeout?: number;
};
The type of options argument of downloadFile().
-
fromUrl
— string — URL to download file from.
-
toFile
— string — Local filesystem path to save the file to.
-
headers
— StringMapT — Optional. An object of headers to be
passed to the server.
-
background
— boolean — Optional. Continue the download in
the background after the app terminates (iOS only).
See Background Downloads Tutorial (iOS).
Defaults false.
-
discretionary
— boolean — Optional. Allow the OS to control
the timing and speed of the download to improve perceived performance
(iOS only).
-
cacheable
— boolean — Optional. Whether the download can be
stored in the shared NSURLCache (iOS only, defaults to true).
-
progressInterval
— number Optional. If provided, the download
progress events will be emitted with the maximum frequency of progressInterval
.
For example, if progressInterval
= 100, you will not receive callbacks more
often than every 100th millisecond.
-
progressDivider
— number Optional. If provided, the download
progress events are emitted at progressDivider
number of steps.
For example, if progressDivider
= 10, you will receive only ten callbacks
for this values of progress: 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100.
Use it for performance issues.
If progressDivider
= 0, you will receive all progressCallback
calls,
default value is 0.
-
begin
— (res: DownloadBeginCallbackResultT) => void —
Optional; required if progress
prop provided. If provided, it is invoked
when download starts, once headers have been received, and it is passed
a single argument of DownloadBeginCallbackResultT type.
-
progress
— (res: DownloadProgressCallbackResultT) => void —
Optional. If provided, it is being invoked continuously and passed in a single
argument of DownloadProgressCallbackResultT type.
-
resumable
— () => void — Optional. iOS-only. If provided,
it is invoked when the download has stopped and and can be resumed using resumeDownload().
-
connectionTimeout
— number — Optional. Only supported on
Android yet.
-
readTimeout
— number Optional. Supported on Android and iOS.
-
backgroundTimeout
— number — Optional. Maximum time
(in milliseconds) to download an entire resource (iOS only, useful for timing
out background downloads).
DownloadProgressCallbackResultT
type DownloadProgressCallbackResultT = {
jobId: number;
contentLength: number;
bytesWritten: number;
};
The type of argument passed to the progress
callback in DownloadFileOptionsT.
jobId
— number The download job ID, required if one wishes
to cancel the download. See stopDownload().contentLength
— number — The total size in bytes of
the download resource.bytesWritten
— number — The number of bytes written to
the file so far.
DownloadResultT
type DownloadResultT = {
jobId: number;
statusCode: number;
bytesWritten: number;
};
Return type of downloadFile().
jobId
— number — The download job ID, required if one wishes
to cancel the download. See stopDownload().statusCode
— number — The HTTP status code.bytesWritten
— number — The number of bytes written to
the file.
EncodingT
type EncodingT = 'ascii' | 'base64' | `utf8`;
Union of valid file encoding values.
FileOptionsT
type FileOptionsT = {
NSFileProtectionKey?: string;
};
The type of additional options for copyFile().
FSInfoResultT
type FSInfoResultT = {
freeSpace: number;
freeSpaceEx: number;
totalSpace: number;
totalSpaceEx: number;
};
The type of result resolved by getFSInfo().
freeSpace
— number — Free storage space on the device,
in bytes.totalSpace
— number — The total storage space on the device,
in bytes.
BEWARE: The following values have been seen reported on Android, but they
are not reported on iOS, probably neither on other systems, and they should be
further checked / fixed.
freeSpaceEx
— number — Free storage space in the external
storage, in bytes.totalSpaceEx
— number — The total storage space in
the external storage, in bytes.
MkdirOptionsT
type MkdirOptionsT = {
NSURLIsExcludedFromBackupKey?: boolean;
};
Type of extra options argument for mkdir().
NSURLIsExcludedFromBackupKey
— boolean | undefined —
(iOS only) The property can be provided to set this attribute on iOS platforms.
Apple will reject apps for storing offline cache data that does not have this
attribute.
PickFileOptionsT
type PickFileOptionsT = {
mimeTypes?: string[];
};
Optional parameters for pickFile() function.
mimeTypes
— string[] — Optional. An array of
MIME types
of files user is allowed to select. Defaults to ['*/*']
allowing to select
any file.
ReadDirAssetsResItemT
type ReadDirAssetsResItemT = {
name: string;
path: string;
size: string;
isFile: () => boolean;
isDirectory: () => boolean;
};
Type of result elements returned by the readDirAssets() function.
name
— string — Item name.path
— string — Item path.size
— string — Size in bytes. Note that the size of files
compressed during the creation of the APK (such as JSON files) cannot be
determined. size
will be set to -1 in this case.isFile
— () => boolean — Is this item a regular file?isDirectory
— () => boolean — Is this item a directory?
ReadDirResItemT
type ReadDirResItemT = {
ctime: Date | null;
mtime: Date;
name: string;
path: string;
size: number;
isFile: () => boolean;
isDirectory: () => boolean;
};
The type of objects returned by the readDir() function.
ctime
— Date | null — Item creation date (iOS only;
null on other platforms).isDirectory
— () => boolean — Evaluates true if item is
a folder; false otherwise.isFile
— () => boolean — Evaluates true if item is
a file; false otherwise.mtime
— Date — The last modified date of the item.name
— string — Name of the item.path
— string — Absolute path of the item.size
— number — Item size in bytes.
ReadFileOptionsT
type ReadFileOptionsT = {
encoding?: EncodingT;
};
The type of extra options argument of the readFile() function.
encoding
— EncodingT | undefined — Optional. File encoding.
Defaults utf8
.
StatResultT
type StatResultT = {
ctime: Date;
isDirectory: () => boolean;
isFile: () => boolean;
mode: undefined;
mtime: Date;
originalFilepath: string;
path: string;
size: number;
};
The type of result resolved by stat().
ctime
— Date — Item's creation date.isDirectory
— () => boolean — Evaluates true if the item
is a folder; false otherwise.isFile
— () => boolean — Evaluates true if the item is
a file; false otherwise.mode
— number | undefined — UNIX file mode; undefined
on platforms that currnetly do not support it (Android).mtime
— Date — Item's last modification date.originalFilepath
— string — (Android-only) In case
of content uri this is the pointed file path, otherwise is the same as path
.path
— string — Item path.size
— number — Item size in bytes.
StringMapT
type StringMapT = { [key: string]: string };
Just a simple string-to-string mapping.
UploadBeginCallbackArgT
type UploadBeginCallbackArgT = {
jobId: number;
};
The type of begin
callback argument in UploadFileOptionsT.
jobId
— number — The upload job ID, required if one wishes
to cancel the upload. See stopUpload().
UploadFileItemT
type UploadFileItemT = {
name?: string;
filename: string;
filepath: string;
filetype?: string;
};
The type of files
elements in UploadFileOptionsT objects.
-
name
— string | undefined — Optional Name of the file,
if not defined then filename
is used.
-
filename
— string — Name of file.
-
filepath
— string — Path to file.
-
filetype
— string | undefined — Optional. The mimetype
of the file to be uploaded, if not defined it will get mimetype from
filepath
extension.
UploadFileOptionsT
type UploadFileOptionsT = {
toUrl: string;
binaryStreamOnly?: boolean;
files: UploadFileItem[];
headers?: StringMapT;
fields?: StringMapT;
method?: string;
begin?: (res: UploadBeginCallbackArgT) => void;
progress?: (res: UploadProgressCallbackArgT) => void;
};
Type of options object in uploadFiles() function.
-
toUrl
— string — URL to upload file to.
-
binaryStreamOnly
— boolean | undefined — Optional.
Allow for binary data stream for file to be uploaded without extra headers.
Defaults false.
-
files
— UploadFileItemT[] — An array of objects with the file
information to be uploaded.
-
headers
— StringMapT | undefined — Optional. An object of
headers to be passed to the server.
-
fields
— StringMapT | undefined — Optional. An object of
fields to be passed to the server.
-
method
— string | undefined — Optional. Defaults POST
,
supports POST
and PUT
.
-
begin
— (res: UploadBeginCallbackArgT) => void —
Optional. If provided, it will be invoked once upon upload has begun.
-
progress
— (res: UploadProgressCallbackArgT) => void —
Optional. If provided, it will be invoked continuously and passed a single
object of UploadProgressCallbackArgT type.
UploadProgressCallbackArgT
type UploadProgressCallbackArgT = {
jobId: number;
totalBytesExpectedToSend: number;
totalBytesSent: number;
};
The type of progress
callback argument in UploadFileOptionsT.
Percentage can be computed easily by dividing totalBytesSent
by
totalBytesExpectedToSend
.
jobId
— number — The upload job ID, required if one wishes
to cancel the upload. See stopUpload().totalBytesExpectedToSend
number — The total number of bytes that
will be sent to the servertotalBytesSent
— number — The number of bytes sent to
the server
UploadResultT
type UploadResultT = {
jobId: number;
statusCode: number;
headers: StringMapT;
body: string;
};
The type of resolved uploadFiles() promise.
-
jobId
— number — The upload job ID, required if one wishes
to cancel the upload. See stopUpload().
-
statusCode
— number — The HTTP status code.
-
headers
— StringMapT — The HTTP response headers from
the server.
-
body
— string — The HTTP response body.
WriteFileOptionsT
type WriteFileOptionsT = {
encoding?: EncodingT;
NSFileProtectionKey?: string;
};
The type of extra options argument of the writeFile() function.