Simple file system API for iOS & Android, for dealing with text-files.

All interaction is promise-based, and all content is written and read as UTF-8.

This library is still under development, and only works on iOS at the current moment.

npm install react-native-filesystem --save
react-native link realm

import FileSystem from 'react-native-filesystem';

async function writeFile() {
  const fileContents = 'This is a my content.';
  await FileSystem.writeToFile('my-directory/my-file.txt', fileContents);
  console.log('file is written');
}

Sub-directories are created automatically.

async function readFile() {
  const fileContents = await FileSystem.readFile('my-directory/my-file.txt');
  console.log(`read from file: ${fileContents}`);
}

async function deleteFile() {
  await FileSystem.delete('my-directory/my-file.txt');
  console.log('file is deleted');
}

async function checkIfFileExists() {
  const fileExists = await FileSystem.fileExists('my-directory/my-file.txt');
  const directoryExists = await FileSystem.fileExists('my-directory/my-file.txt');
  console.log(`file exists: ${fileExists}`);
  console.log(`directory exists: ${directoryExists}`);
}

All commands also takes an optional last argument specifying storage. These locations roughly corresponds to the four points of the iOS Data Storage Guidelines, and have similar behaviour on Android.

FileSystem.writeFile('my-file.txt', 'My content', FileSystem.storage.important);

Files need to be read from the same storage they're saved to, and two files can have the same name if they're located in different storages. The options are:

The default. Files stored in this location will automatically be backed up by iCloud on iOS and Auto Backup for Apps on Android. This is generally for user-generated content that cannot be re-generated / re-downloaded.

Corresponds to <Application_Home>/Documents on iOS and Context.getFilesDir() on Android.

This is for files that are possible to re-generate / re-download, but are still important to keep around. F.ex. offline maps.

Corresponds to <Application_Home>/<Application_Home>/Library/Caches with "do not backup" flag on iOS and Context.getNoBackupFilesDir() on Android.

This storage class is for files that can be re-created, and are not crucial to the proper functioning of your app.

Corresponds to <Application_Home>/<Application_Home>/Library/Caches on iOS and Context.getExternalCacheDir() on Android.

Location for temporary caches and data. You should still clean up / delete the files when they are no longer in use.

Corresponds to <Application_Home>/tmp on iOS and Context.getCacheDir() on Android.

Why yet another file system library?

I simply couldn't find one that satisified my basic needs for simplicity.

Why not use the built-in AsyncStorage?

AsyncStorage is fine, but some times you want more control as to where the content is stored. This library lets you put it in backed-up folders, or play nice by marking content that can be deleted when the phone runs low on space.