react-native-file-access

react-native-file-access

Filesystem access for React Native. Supports saving network requests directly to the filesystem. Supports Android scoped storage, a requirement when targeting API 30 or higher.

Installation

npm install react-native-file-access

Compatibility

For React Native 0.64 and older, use 1.x.x. For React Native 0.65+, use 2.x.x.

Usage

import { Dirs, FileSystem } from 'react-native-file-access';

// ...

const text = await FileSystem.readFile(Dirs.CacheDir + '/test.txt');

Directory constants.

• Dirs.CacheDir
• Dirs.DatabaseDir (Android only)
• Dirs.DocumentDir
• Dirs.LibraryDir (iOS & MacOS only)
• Dirs.MainBundleDir
• Dirs.SDCardDir (Android only)
  • Prefer FileSystem.cpExternal() when possible.

Functions.

FileSystem.appendFile(path: string, data: string, encoding?: 'utf8' | 'base64'): Promise<void>

• Append content to a file.
  • Default encoding of data is assumed utf8.

FileSystem.concatFiles(source: string, target: string): Promise<number>

• Append a file to another file. Returns number of bytes written.

FileSystem.cp(source: string, target: string): Promise<void>

• Copy a file.

FileSystem.cpAsset(asset: string, target: string, type?: 'asset' | 'resource'): Promise<void>

• Copy a bundled asset file.
  • Default type is asset. Prefer this when possible.
  • resource uses the Android res/ folder, and inherits the associated naming restrictions.

FileSystem.cpExternal(source: string, targetName: string, dir: 'audio' | 'downloads' | 'images' | 'video'): Promise<void>

• Copy a file to an externally controlled location.
  • On Android API level < 29, may require permission WRITE_EXTERNAL_STORAGE.
  • On iOS, consider using Dirs.DocumentDir with UIFileSharingEnabled and LSSupportsOpeningDocumentsInPlace enabled.

FileSystem.df(): Promise<{ internal_free: number, internal_total: number, external_free?: number, external_total?: number }>

• Check device available space.

FileSystem.exists(path: string): Promise<boolean>

• Check if a path exists.

FilesSystem.fetch(
  resource: string,
  init: { body?: string, headers?: { [key: string]: string }, method?: string, path?: string },
  onProgress?: (bytesRead: number, contentLength: number, done: boolean) => void
): Promise<FetchResult>

type FetchResult = {
  headers: { [key: string]: string };
  ok: boolean;
  redirected: boolean;
  status: number;
  statusText: string;
  url: string;
}

• Save a network request to a file.
  • onProgress - Optional callback to listen to download progress. Events are rate limited, so do not rely on done becoming true. contentLength is only accurate if the server sends the correct headers.

FilesSystem.fetchManaged(
  resource: string,
  init: { body?: string, headers?: { [key: string]: string }, method?: string, path?: string },
  onProgress?: (bytesRead: number, contentLength: number, done: boolean) => void
): ManagedFetchResult

type ManagedFetchResult = {
  cancel: () => Promise<void>;
  result: Promise<FetchResult>;
}

• Save a network request to a file.
  • Similar to fetch(), with the option to cancel before completion.

FilesSystem.getAppGroupDir(groupName: string): Promise<string>

• Get the directory for your app group (iOS & MacOS only).
  • App groups are used on iOS/MacOS for storing content, which is shared between apps.
  • This is e.g. useful for sharing data between your iOS/MacOS app and a widget or a watch app.

FilesSystem.hash(path: string, algorithm: 'MD5' | 'SHA-1' | 'SHA-224' | 'SHA-256' | 'SHA-384' | 'SHA-512'): Promise<string>

• Hash the file content.

FilesSystem.isDir(path: string): Promise<boolean>

• Check if a path is a directory.

FileSystem.ls(path: string): Promise<string[]>

• List files in a directory.

FileSystem.mkdir(path: string): Promise<void>

• Make a new directory.

FileSystem.mv(source: string, target: string): Promise<void>

• Move a file.

FileSystem.readFile(path: string, encoding?: 'utf8' | 'base64'): Promise<string>

• Read the content of a file.
  • Default encoding of returned string is utf8.

FileSystem.stat(path: string): Promise<FileStat>

type FileStat = {
  filename: string;
  lastModified: number;
  path: string;
  size: number;
  type: 'directory' | 'file';
}

• Read file metadata.

FileSystem.unlink(path: string): Promise<void>

• Delete a file.

FileSystem.writeFile(path: string, data: string, encoding?: 'utf8' | 'base64'): Promise<void>

• Write content to a file.
  • Default encoding of data is assumed utf8.

Testing

For ease of testing, this library contains a mock implementation: jest/react-native-file-access.ts. To use, copy it into the __mocks__ folder, modifying if needed.

Alternatives

This library aims to be a modern implementation of filesystem api, using Kotlin/Swift and latest best practices. For a more established library, consider:

• expo-file-system
  • Well supported, a good option if already using Expo.
• rn-fetch-blob
  • Popular, and often a dependency of other libraries.
  • Officially unmaintained, with known bugs.
• react-native-fs
  • Large feature set.
  • Low maintenance, aging codebase.

For more greater control over network requests, consider react-native-blob-courier.

Contributing

See the contributing guide to learn how to contribute to the repository and the development workflow.

License

MIT