How to work with file paths in Node.js

The path module in Node.js provides utilities for handling and transforming file and directory paths in a way that is independent of the operating system.

It is a good practice to use these functions instead of manually splitting and concatenating strings.

Additionally, because they are operating system independent, your code will work correctly on different operating systems, such as Windows, macOS, and Linux.

Functions of the Path Module

Let’s look at some of the most important functions of the path module, along with practical examples of how to use them.

Joining Paths

The join function of the path module is used to join multiple parts of a path into a single complete path.

import path from 'node:path';

const path1 = '/folder1';
const path2 = 'subfolder/file.txt';

const completePath = path.join(path1, path2);
console.log('Complete path:', completePath);

Normalizing a Path

Path normalization is important for removing redundancies and simplifying paths. The normalize function of the path module allows you to do this easily.

import path from 'node:path';

const path = '/folder1//subfolder/./file.txt';
const normalizedPath = path.normalize(path);

console.log('Normalized path:', normalizedPath);
// Normalized path: \folder1\subfolder\file.txt

Getting the File Name

The basename function allows you to get the base name of a file from a given path.

import path from 'node:path';

const path = '/folder1/subfolder/file.txt';
const baseName = path.basename(path);

console.log('File name:', baseName);
//File name: file.txt

Getting the Directory Name

To get the directory name from a given path, you can use the dirname function.

import path from 'node:path';

const path = '/folder1/subfolder/file.txt';
const directoryName = path.dirname(path);

console.log('Directory name:', directoryName);
//Directory name: /folder1/subfolder

Getting the File Extension

With the extname function, you can get the extension of a file from a given path.

import path from 'node:path';

const path = '/folder1/subfolder/file.txt';
const extension = path.extname(path);

console.log('File extension:', extension);
// File extension: .txt

Converting a Relative Path to Absolute

To convert a relative path to an absolute path, you can use the resolve function.

import path from 'node:path';

const relativePath = '../folder1/subfolder/file.txt';
const absolutePath = path.resolve(relativePath);

console.log('Absolute path:', absolutePath);
// Absolute path: C:\..whatever..\folder1\subfolder\file.txt

Download the Code

All the code from this entry is available for download on Github