mime-kind

Detect the MIME type of a Buffer, Uint8Array, ArrayBuffer, ReadableStream, file path and file name, with async method.

Install

$ npm install mime-kind --save

Usage

const { createReadStream } = require('fs');
const mime = require('mime-kind');

await mime('.fakeext'); // -> null
await mime(createReadStream('./anonim.jpg')); // -> { ext: 'jpeg', mime: 'image/jpeg' }
await mime('c:/anonim.jpeg'); // -> { ext: 'jpeg', mime: 'image/jpeg' }

API

mime(input, [defaultValue])

mime.async(input, [defaultValue])

Returns a Promise with an object (or null when no match) with:

• ext - file type
• mime - the MIME type

This methods supports all kind of ReadableStreams.

Params:

• input (String|Buffer|Uint8Array|ArrayBuffer|ReadableStream) - Buffer, Uint8Array, ArrayBuffer, ReadableStream, file path or file name.
• [defaultValue] (String|Object) - String or Object with value which will be returned if no match will be found. If defaultValue is incorrect returns null.

const mime = require('mime-kind');

await mime('.fakeext', 'application/octet-stream'); // -> { ext: 'bin', mime: 'application/octet-stream' }
await mime.async('.fakeext', { ext: 'mp4', mime: 'video/mp4' }); // -> { ext: 'mp4', mime: 'video/mp4' }
await mime.async('.fakeext', 'ogg'); // -> { ext: 'ogg', mime: 'audio/ogg' }
// but
await mime.async('.fakeext', 'ogg3'); // -> null
await mime('.fakeext', { ext: 'fake', mime: 'fake/fake' }); // -> null

With HTTP(S) streams:

const mime = require('mime-kind');
const { get } = require('https');
const { PassThrough } = require('stream');

const pass = new PassThrough();
get('https://avatars0.githubusercontent.com/u/2401029', res => res.pipe(pass));
await mime(pass); // -> { ext: 'jpg', mime: 'image/jpeg' }

License

The MIT License (MIT) Copyright (c) 2015-2022 Alexey Bystrov