To help you get started, we've collected the most common ways that react-native-fs is being used within popular public projects.

react-native-fs

Native filesystem access for react-native

IMPORTANT

For RN < 0.57 and/or Gradle < 3 you MUST install react-native-fs at version @2.11.17!

For RN >= 0.57 and/or Gradle >= 3 you MUST install react-native-fs at version >= @2.13.2!

For RN >= 0.61 please install react-native-fs at version >= @2.16.0!

Table of Contents

1. Changelog
2. Usage
   1. iOS
   2. Android
   3. Windows
3. Examples
4. API
5. Background Downloads Tutorial (iOS)
6. Test / Demo App

Changelog

View the changelog here.

Usage (iOS/macOS)

First you need to install react-native-fs:

npm install react-native-fs --save

Note: If your react-native version is < 0.40 install with this tag instead:

npm install react-native-fs@2.0.1-rc.2 --save

As @a-koka pointed out, you should then update your package.json to "react-native-fs": "2.0.1-rc.2" (without the tilde)

Adding automatically with react-native link

At the command line, in your project folder, type:

react-native link react-native-fs

Done! No need to worry about manually adding the library to your project.

Adding with CocoaPods

Add the RNFS pod to your list of application pods in your Podfile, using the path from the Podfile to the installed module:~~

pod 'RNFS', :path => '../node_modules/react-native-fs'

Install pods as usual:

pod install

Adding Manually in XCode

In XCode, in the project navigator, right click Libraries ➜ Add Files to [your project's name] Go to node_modules ➜ react-native-fs and add the .xcodeproj file

In XCode, in the project navigator, select your project. Add the lib*.a from the RNFS project to your project's Build Phases ➜ Link Binary With Libraries. Click the .xcodeproj file you added before in the project navigator and go the Build Settings tab. Make sure 'All' is toggled on (instead of 'Basic'). Look for Header Search Paths and make sure it contains both $(SRCROOT)/../react-native/React and $(SRCROOT)/../../React - mark both as recursive.

Run your project (Cmd+R)

Usage (Android)

Android support is currently limited to only the DocumentDirectory. This maps to the app's files directory.

Make alterations to the following files:

• android/settings.gradle

...
include ':react-native-fs'
project(':react-native-fs').projectDir = new File(settingsDir, '../node_modules/react-native-fs/android')

• android/app/build.gradle

...
dependencies {
    ...
    implementation project(':react-native-fs')
}

• register module (in MainActivity.java)

  • For react-native below 0.19.0 (use cat ./node_modules/react-native/package.json | grep version)

import com.rnfs.RNFSPackage;  // <--- import

public class MainActivity extends Activity implements DefaultHardwareBackBtnHandler {

  ......

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    mReactRootView = new ReactRootView(this);

    mReactInstanceManager = ReactInstanceManager.builder()
      .setApplication(getApplication())
      .setBundleAssetName("index.android.bundle")
      .setJSMainModuleName("index.android")
      .addPackage(new MainReactPackage())
      .addPackage(new RNFSPackage())      // <------- add package
      .setUseDeveloperSupport(BuildConfig.DEBUG)
      .setInitialLifecycleState(LifecycleState.RESUMED)
      .build();

    mReactRootView.startReactApplication(mReactInstanceManager, "ExampleRN", null);

    setContentView(mReactRootView);
  }

  ......

}

• For react-native 0.19.0 and higher

import com.rnfs.RNFSPackage; // <------- add package

public class MainActivity extends ReactActivity {
   // ...
    @Override
    protected List getPackages() {
      return Arrays.asList(
        new MainReactPackage(), // <---- add comma
        new RNFSPackage() // <---------- add package
      );
    }

• For react-native 0.29.0 and higher ( in MainApplication.java )

import com.rnfs.RNFSPackage; // <------- add package

public class MainApplication extends Application implements ReactApplication {
   // ...
    @Override
    protected List getPackages() {
      return Arrays.asList(
        new MainReactPackage(), // <---- add comma
        new RNFSPackage() // <---------- add package
      );
    }

Usage (Windows)

Adding automatically with react-native link

The link command also works for adding the native dependency on Windows:

react-native link react-native-fs

Adding Manually in Visual Studio

Follow the instructions in the 'Linking Libraries' documentation on the react-native-windows GitHub repo. For the first step of adding the project to the Visual Studio solution file, the path to the project should be ../node_modules/react-native-fs/windows/RNFS/RNFS.csproj.

Examples

Basic

// require the module
var RNFS = require('react-native-fs');

// get a list of files and directories in the main bundle
RNFS.readDir(RNFS.MainBundlePath) // On Android, use "RNFS.DocumentDirectoryPath" (MainBundlePath is not defined)
  .then((result) => {
    console.log('GOT RESULT', result);

    // stat the first file
    return Promise.all([RNFS.stat(result[0].path), result[0].path]);
  })
  .then((statResult) => {
    if (statResult[0].isFile()) {
      // if we have a file, read it
      return RNFS.readFile(statResult[1], 'utf8');
    }

    return 'no file';
  })
  .then((contents) => {
    // log the file contents
    console.log(contents);
  })
  .catch((err) => {
    console.log(err.message, err.code);
  });

File creation

// require the module
var RNFS = require('react-native-fs');

// create a path you want to write to
// :warning: on iOS, you cannot write into `RNFS.MainBundlePath`,
// but `RNFS.DocumentDirectoryPath` exists on both platforms and is writable
var path = RNFS.DocumentDirectoryPath + '/test.txt';

// write the file
RNFS.writeFile(path, 'Lorem ipsum dolor sit amet', 'utf8')
  .then((success) => {
    console.log('FILE WRITTEN!');
  })
  .catch((err) => {
    console.log(err.message);
  });

File deletion

// create a path you want to delete
var path = RNFS.DocumentDirectoryPath + '/test.txt';

return RNFS.unlink(path)
  .then(() => {
    console.log('FILE DELETED');
  })
  // `unlink` will throw an error, if the item to unlink does not exist
  .catch((err) => {
    console.log(err.message);
  });

File upload (Android and IOS only)

// require the module
var RNFS = require('react-native-fs');

var uploadUrl = 'https://requestb.in/XXXXXXX';  // For testing purposes, go to https://requestb.in/ and create your own link
// create an array of objects of the files you want to upload
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!');
};

// upload files
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!'); // response.statusCode, response.headers, response.body
    } else {
      console.log('SERVER ERROR');
    }
  })
  .catch((err) => {
    if(err.description === "cancelled") {
      // cancelled by user
    }
    console.log(err);
  });

API

Constants

The following constants are available on the RNFS export:

• MainBundlePath (String) The absolute path to the main bundle directory (not available on Android)
• CachesDirectoryPath (String) The absolute path to the caches directory
• ExternalCachesDirectoryPath (String) The absolute path to the external caches directory (android only)
• DocumentDirectoryPath (String) The absolute path to the document directory
• DownloadDirectoryPath (String) The absolute path to the download directory (on android only)
• TemporaryDirectoryPath (String) The absolute path to the temporary directory (falls back to Caching-Directory on Android)
• LibraryDirectoryPath (String) The absolute path to the NSLibraryDirectory (iOS only)
• ExternalDirectoryPath (String) The absolute path to the external files, shared directory (android only)
• ExternalStorageDirectoryPath (String) The absolute path to the external storage, shared directory (android only)

IMPORTANT: 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

readDir(dirpath: string): Promise

Reads the contents of path. This must be an absolute path. Use the above path constants to form a usable file path.

The returned promise resolves with an array of objects with the following properties:

type ReadDirItem = {
  ctime: date;     // The creation date of the file (iOS only)
  mtime: date;     // The last modified date of the file
  name: string;     // The name of the item
  path: string;     // The absolute path to the item
  size: string;     // Size in bytes
  isFile: () => boolean;        // Is the item just a file?
  isDirectory: () => boolean;   // Is the item a directory?
};

readDirAssets(dirpath: string): Promise

Reads the contents of dirpath in the Android app's assets folder. dirpath is the relative path to the file from the root of the assets folder.

The returned promise resolves with an array of objects with the following properties:

type ReadDirItem = {
  name: string;     // The name of the item
  path: string;     // The absolute path to the item
  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 the file just a file?
  isDirectory: () => boolean;   // Is the file a directory?
};

Note: Android only.

readdir(dirpath: string): Promise

Node.js style version of readDir that returns only the names. Note the lowercase d.

stat(filepath: string): Promise

Stats an item at filepath. If the filepath is linked to a virtual file, for example Android Content URI, the originalPath can be used to find the pointed file path. The promise resolves with an object with the following properties:

type StatResult = {
  path:            // The same as filepath argument
  ctime: date;     // The creation date of the file
  mtime: date;     // The last modified date of the file
  size: number;     // Size in bytes
  mode: number;     // UNIX file mode
  originalFilepath: string;    // ANDROID: In case of content uri this is the pointed file path, otherwise is the same as path
  isFile: () => boolean;        // Is the file just a file?
  isDirectory: () => boolean;   // Is the file a directory?
};

readFile(filepath: string, encoding?: string): Promise

Reads the file at path and return contents. encoding can be one of utf8 (default), ascii, base64. Use base64 for reading binary files.

Note: you will take quite a performance hit if you are reading big files

read(filepath: string, length = 0, position = 0, encodingOrOptions?: any): Promise

Reads length bytes from the given position of the file at path and returns contents. encoding can be one of utf8 (default), ascii, base64. Use base64 for reading binary files.

Note: reading big files piece by piece using this method may be useful in terms of performance.

readFileAssets(filepath:string, encoding?: string): Promise

Reads the file at path in the Android app's assets folder and return contents. encoding can be one of utf8 (default), ascii, base64. Use base64 for reading binary files.

filepath is the relative path to the file from the root of the assets folder.

Note: Android only.

readFileRes(filename:string, encoding?: string): Promise

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. The file type will be detected from the extension and automatically located within res/drawable (for image files) or res/raw (for everything else). encoding can be one of utf8 (default), ascii, base64. Use base64 for reading binary files.

Note: Android only.

writeFile(filepath: string, contents: string, encoding?: string): Promise

Write the contents to filepath. encoding can be one of utf8 (default), ascii, base64. options optionally takes an object specifying the file's properties, like mode etc.

appendFile(filepath: string, contents: string, encoding?: string): Promise

Append the contents to filepath. encoding can be one of utf8 (default), ascii, base64.

write(filepath: string, contents: string, position?: number, encoding?: string): Promise

Write the contents to filepath at the given random access position. When position is undefined or -1 the contents is appended to the end of the file. encoding can be one of utf8 (default), ascii, base64.

moveFile(filepath: string, destPath: string): Promise

Moves the file located at filepath to destPath. 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.

copyFile(filepath: string, destPath: string): Promise

Copies the file located at filepath to destPath.

Note: On Android copyFile will overwrite destPath if it already exists. On iOS an error will be thrown if the file already exists.

copyFileAssets(filepath: string, destPath: string): Promise

Copies the file at filepath in the Android app's assets folder and copies it to the given destPath path.

Note: Android only. Will overwrite destPath if it already exists.

copyFileRes(filename: string, destPath: string): Promise

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.

Note: Android only. Will overwrite destPath if it already exists.

(iOS only) copyAssetsFileIOS(imageUri: string, destPath: string, width: number, height: number, scale?: number, compression?: number, resizeMode?: string): Promise

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.

Parameters

imageUri string (required)

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 (required)

Destination to which the copied file will be saved, e.g. RNFS.TemporaryDirectoryPath + 'example.jpg'.

width number (required)

Copied file's image width will be resized to width. If 0 is provided, width won't be resized.

height number (required)

Copied file's image height will be resized to height. If 0 is provided, height won't be resized.

scale number (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 (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 (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.

Return value

Promise

Copied file's URI.

Video-Support

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 wich 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.

(iOS only) copyAssetsVideoIOS(videoUri: string, destPath: string): Promise

Not available on Mac Catalyst.

Copies a video from assets-library, that is prefixed with 'assets-library://asset/asset.MOV?...' to a specific destination.

unlink(filepath: string): Promise

Unlinks the item at filepath. If the item does not exist, an error will be thrown.

Also recursively deletes directories (works like Linux rm -rf).

exists(filepath: string): Promise

Check if the item exists at filepath. If the item does not exist, return false.

existsAssets(filepath: string): Promise

Check in the Android assets folder if the item exists. filepath is the relative path from the root of the assets folder. If the item does not exist, return false.

Note: Android only.

existsRes(filename: string): Promise

Check in the Android res folder if the item named filename exists. res/drawable is used as the parent folder for image files, res/raw for everything else. If the item does not exist, return false.

Note: Android only.

hash(filepath: string, algorithm: string): Promise

Reads the file at path and returns its checksum as determined by algorithm, which can be one of md5, sha1, sha224, sha256, sha384, sha512.

touch(filepath: string, mtime?: Date, ctime?: Date): Promise

Sets the modification timestamp mtime and creation timestamp ctime of the file at filepath. Setting ctime is only supported on iOS, android always sets both timestamps to mtime.

mkdir(filepath: string, options?: MkdirOptions): Promise

type MkdirOptions = {
  NSURLIsExcludedFromBackupKey?: boolean; // iOS only
};

Create a directory at filepath. Automatically creates parents and does not throw if already exists (works like Linux mkdir -p).

(IOS only): The NSURLIsExcludedFromBackupKey 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.

downloadFile(options: DownloadFileOptions): { jobId: number, promise: Promise }

type DownloadFileOptions = {
  fromUrl: string;          // URL to download file from
  toFile: string;           // Local filesystem path to save the file to
  headers?: Headers;        // An object of headers to be passed to the server
  background?: boolean;     // Continue the download in the background after the app terminates (iOS only)
  discretionary?: boolean;  // Allow the OS to control the timing and speed of the download to improve perceived performance  (iOS only)
  cacheable?: boolean;      // Whether the download can be stored in the shared NSURLCache (iOS only, defaults to true)
  progressInterval?: number;
  progressDivider?: number;
  begin?: (res: DownloadBeginCallbackResult) => void; // Note: it is required when progress prop provided
  progress?: (res: DownloadProgressCallbackResult) => void;
  resumable?: () => void;    // only supported on iOS yet
  connectionTimeout?: number // only supported on Android yet
  readTimeout?: number       // supported on Android and iOS
  backgroundTimeout?: number // Maximum time (in milliseconds) to download an entire resource (iOS only, useful for timing out background downloads)
};

type DownloadResult = {
  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
};

Download file from options.fromUrl to options.toFile. Will overwrite any previously existing file.

If options.begin is provided, it will be invoked once upon download starting when headers have been received and passed a single argument with the following properties:

type DownloadBeginCallbackResult = {
  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: Headers;       // The HTTP response headers from the server
};

If options.progress is provided, it will be invoked continuously and passed a single argument with the following properties:

type DownloadProgressCallbackResult = {
  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
};

If options.progressInterval is provided, it will return progress events in the maximum frequency of progressDivider. For example, if progressInterval = 100, you will not receive callbacks more often than every 100th millisecond.

If options.progressDivider is provided, it will return progress events that divided by progressDivider.

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.

(IOS only): options.background (Boolean) - Whether to continue downloads when the app is not focused (default: false) This option is currently only available for iOS, see the Background Downloads Tutorial (iOS) section.

(IOS only): If options.resumable is provided, it will be invoked when the download has stopped and and can be resumed using resumeDownload().

stopDownload(jobId: number): void

Abort the current download job with this ID. The partial file will remain on the filesystem.

(iOS only) resumeDownload(jobId: number): void

Resume the current download job with this ID.

(iOS only) isResumable(jobId: number): Promise

Check if the the download job with this ID is resumable with resumeDownload().

Example:

if (await RNFS.isResumable(jobId) {
    RNFS.resumeDownload(jobId)
}

(iOS only) completeHandlerIOS(jobId: number): void

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.

uploadFiles(options: UploadFileOptions): { jobId: number, promise: Promise }

options (Object) - An object containing named parameters

type UploadFileOptions = {
  toUrl: string;            // URL to upload file to
  binaryStreamOnly?: boolean// Allow for binary data stream for file to be uploaded without extra headers, Default is 'false'
  files: UploadFileItem[];  // An array of objects with the file information to be uploaded.
  headers?: Headers;        // An object of headers to be passed to the server
  fields?: Fields;          // An object of fields to be passed to the server
  method?: string;          // Default is 'POST', supports 'POST' and 'PUT'
  begin?: (res: UploadBeginCallbackResult) => void;
  progress?: (res: UploadProgressCallbackResult) => void;
};

type UploadResult = {
  jobId: number;        // The upload job ID, required if one wishes to cancel the upload. See `stopUpload`.
  statusCode: number;   // The HTTP status code
  headers: Headers;     // The HTTP response headers from the server
  body: string;         // The HTTP response body
};

Each file should have the following structure:

type UploadFileItem = {
  name: string;       // Name of the file, if not defined then filename is used
  filename: string;   // Name of file
  filepath: string;   // Path to file
  filetype: string;   // The mimetype of the file to be uploaded, if not defined it will get mimetype from `filepath` extension
};

If options.begin is provided, it will be invoked once upon upload has begun:

type UploadBeginCallbackResult = {
  jobId: number;        // The upload job ID, required if one wishes to cancel the upload. See `stopUpload`.
};

If options.progress is provided, it will be invoked continuously and passed a single object with the following properties:

type UploadProgressCallbackResult = {
  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 server
  totalBytesSent: number;             // The number of bytes sent to the server
};

Percentage can be computed easily by dividing totalBytesSent by totalBytesExpectedToSend.

(iOS only) stopUpload(jobId: number): Promise

Abort the current upload job with this ID.

getFSInfo(): Promise

Returns an object with the following properties:

type FSInfoResult = {
  totalSpace: number;   // The total amount of storage space on the device (in bytes).
  freeSpace: number;    // The amount of available storage space on the device (in bytes).
};

(Android only) scanFile(path: string): Promise

Scan the file using Media Scanner.

(Android only) getAllExternalFilesDirs(): Promise

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.

(iOS only) pathForGroup(groupIdentifier: string): Promise

groupIdentifier (string) Any value from the com.apple.security.application-groups entitlements list.

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.

Background Downloads Tutorial (iOS)

Background downloads in iOS require a bit of a setup.

First, in your AppDelegate.m file add the following:

#import 

...

- (void)application:(UIApplication *)application handleEventsForBackgroundURLSession:(NSString *)identifier completionHandler:(void (^)())completionHandler
{
  [RNFSManager 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.

Test / Demo app

Test app to demostrate the use of the module. Useful for testing and developing the module:

https://github.com/cjdell/react-native-fs-test