fs-handy-wraps

Handy Wraps for Node.js FS

A pretty simple library. It uses fs-extra under the hood.

Installation

npm i -S fs-handy-wraps or yarn add fs-handy-wraps

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Constants

HOME is a path to the Home directory of the current OS user.

CWD is a path to the Current Working Directory.

fse is an object that exposes fs-extra functions as is.

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Functions for Reading and Writing files

All the functions are promisified. Only first argument is required.

check (path[, existCallback, absentCallback])

Checks the file existence. All arguments are required.

read (path[, successCallback, errCallback])

Reads the file contents.

write (path[, text, successCallback, errCallback])

Rewrites the file content by text or an empty string. Also may be used for a new file creation. If the target folder does not exist, it will be created.

rm (path)

Removes specified file of folder as it rm -rf does. Resolves to a true value if succeeded.

append (path[, text, successCallback, errCallback])

Appends text or an empty string to the end of the file.

rom (path[, make, readCallback])

Reads the file if it exists and calls readCallback then. Creates a new file if it does not exist. If argument make is not specified new file will be empty. If typeof make === string it will be the content of the new file. If typeof make === function it will be a callback with arguments: (resolve, reject). This callback should call resolve with a content for the new file. See examples below.

dir (path[, successCallback, errCallback])

Creates a directory specified by path. This function is imported from fs-extra. Here is its documentation.

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Read or Create a JSON config-file using simple CLI

getConfig (path[, defProvider, CLIQuestions, successCallback, errCallback])

Reads the path file, checks if for JSON errors and calls successCallback (parsedConfig). If the file does not exist -- creates it according to default content provided by defProvider. defProvider may be: an object or a function that returns an object or a promise. If CLIQuestions specified, a simple CLI will be started. Example for CLIQuestions object:

const CLIQuestions_EXAMPLE = [
    { prop: 'pathToBase',     question: 'Full path to database file:' },
    { prop: 'pathToNotefile', question: 'Path to temp file:' },
    { prop: 'editor',         question: 'Command to open your text editor:' },
];

It asks CLIQuestions to user, then assigns received values to a default object. A callback successCallback (config) will be executed in the result.

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Watching on file changes

Only for for testing purposes. In production, use chokidar instead.

This function cannot be promisified.

watch (path, callback)

Creates a Watcher that will call the callback every time a file specified by path is changed. There are a 30ms delay between the system event and the callback is called.

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Usage example (with callbacks)

const FILE = require('fs-handy-wraps');
const configPath = '~/config.json';
const configDefaults = {
    base: '~/base.txt',
    name: 'My new Project'
};
const cli = [
    { prop: 'base', question: 'Where to store the database?' },
    { prop: 'name', question: 'What is the name of your Project?' },
];
 
start();
 
function start() {
    FILE.getConfig (configPath, configDefaults, cli, checkBase);
}
function checkBase (config) {
    FILE.rom (config.base, createNewBase, parseBase);
}
function parseBase (baseContent) {
    // do something with baseContent...
}
function createNewBase (resolve, reject) {
    // do something to get the new base content...
    resolve(content);
}

Usage with promises (async / await syntax)

const FILE = require('fs-handy-wraps');
 
const pathDefaultFile = 'fileDef.txt';
const pathFile = 'file.txt';
 
// if pathFile is already exists --> read it
// else --> create a new file based on the another one.
(async function start() {
    const content = await FILE.rom(pathFile, makeDefault);
    console.log(content);
 
    async function makeDefault(resolve, reject) {
        resolve(await FILE.read(pathDefaultFile));
    }
})()