Node.js file stats

Every file comes with a set of details that we can inspect using Node.js. In particular, using the stat() method provided by the fs module.

You call it passing a file path, and once Node.js gets the file details it will call the callback function you pass, with 2 parameters: an error message, and the file stats:

const fs = require('node:fs');fs.stat('/Users/joe/test.txt', (err, stats) => { if (err) { console.error(err); } // we have access to the file stats in `stats`});

Node.js also provides a sync method, which blocks the thread until the file stats are ready:

const fs = require('node:fs');try { const stats = fs.statSync('/Users/joe/test.txt');} catch (err) { console.error(err);}

The file information is included in the stats variable. What kind of information can we extract using the stats?

A lot, including:

• if the file is a directory or a file, using stats.isFile() and stats.isDirectory()
• if the file is a symbolic link using stats.isSymbolicLink()
• the file size in bytes using stats.size.

There are other advanced methods, but the bulk of what you'll use in your day-to-day programming is this.

const fs = require('node:fs');fs.stat('/Users/joe/test.txt', (err, stats) => { if (err) { console.error(err); return; } stats.isFile(); // true stats.isDirectory(); // false stats.isSymbolicLink(); // false stats.size; // 1024000 //= 1MB});

You can also use promise-based fsPromises.stat() method offered by the fs/promises module if you like:

const fs = require('node:fs/promises');async function example() { try { const stats = await fs.stat('/Users/joe/test.txt'); stats.isFile(); // true stats.isDirectory(); // false stats.isSymbolicLink(); // false stats.size; // 1024000 //= 1MB } catch (err) { console.log(err); }}example();

You can read more about the fs module in the official documentation.