file-manager

This simple module is designed to be an abstraction for file storage. By default, it saves files to disk in a specified directory, but it can easily be overridden to save files to anywhere you want, e.g. a database.

API

Constructor(storageDirectory)

• storageDirectory - The directory on the local disk where files will be stored. Use null to disable local disk storage.

const FileManager = require('file-manager');
const Path = require('path');
let manager = new FileManager(Path.join(__dirname, 'data'));

isEnabled()

Returns true if either a storage directory is set, or if save and read handlers have been registered.

saveFile(filename, contents)

• filename - Obvious
• contents - Either a Buffer, or some other value that will have .toString() called on it, then it will be converted to a Buffer by interpreting the string as UTF-8

Saves a file. Returns a Promise that will be fulfilled once the file is saved, or rejected if there's an error.

Alias: writeFile

saveFiles(files)

• files - An object where keys are filenames and values are file contents

Saves multiple files. Returns a Promise that will be fulfilled once all files are saved, or rejected if there's an error saving any file

Alias: writeFiles

readFile(filename)

• filename - Obvious

Reads a single file. Returns a Promise that fulfills to its content, as a Buffer. Rejects if there's an error or the file doesn't exist.

readFiles(filenames)

• filenames - Array of filenames

Reads multiple files. Returns a Promise that fulfills to an array containing objects of this structure:

• filename - The name of this file
• contents - The content of this file, if reading succeeded
• error - An Error object, if there was an error reading this file (e.g. it doesn't exist)

This function can never reject.

Events

You can register your own save/read handlers by attaching event listeners.

read

• filename - The filename of the file we want to read
• callback - A function you should call once this file's contents are available, or an error occurred
  • err - An Error object if there was an error reading this file (e.g. it doesn't exist). null if no error.
  • contents - A Buffer containing the file's content, if reading succeeded

Emitted when a file is requested to be read.

save

• filename - The filename of the file we want to save
• contents - The content we want to save to this file, as a Buffer
• callback - A function you should call once this file has been saved, or an error occurred
  • err - An Error object if there was an error saving this file. null if no error.

Emitted when a file is requested to be saved.

Properties

directory

The local disk storage directory location can be changed at any time by assigning to the directory property.