Package Exports
- file-type
- file-type/index
This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (file-type) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.
Readme
file-type 
Detect the file type of a Buffer/Uint8Array
The file type is detected by checking the magic number of the buffer.
Install
$ npm install --save file-typeUsage
Node.js
var readChunk = require('read-chunk'); // npm install read-chunk
var fileType = require('file-type');
var buffer = readChunk.sync('unicorn.png', 0, 262);
fileType(buffer);
//=> {ext: 'png', mime: 'image/png'}or from a remote location:
var http = require('http');
var fileType = require('file-type');
var url = 'http://assets-cdn.github.com/images/spinners/octocat-spinner-32.gif';
http.get(url, function (res) {
res.once('data', function (chunk) {
res.destroy();
console.log(fileType(chunk));
//=> {ext: 'gif', mime: 'image/gif'}
});
});Browser
var xhr = new XMLHttpRequest();
xhr.open('GET', 'unicorn.png');
xhr.responseType = 'arraybuffer';
xhr.onload = function () {
fileType(new Uint8Array(this.response));
//=> {ext: 'png', mime: 'image/png'}
};
xhr.send();API
fileType(buffer)
Returns an object (or null when no match) with:
ext- one of the supported file typesmime- the MIME type
buffer
Type: buffer (Node.js), uint8array
It only needs the first 262 bytes.
CLI
$ npm install --global file-type$ file-type --help
Usage
file-type <filename>
cat <filename> | file-type
Example
cat unicorn.png | file-type
pngSupported file types
jpgpnggifwebpcr2tifbmpjxrpsdziptarrargzbz27zmp4m4vmidmkvwebmmovaviwmvmpgmp3m4aoggflacwavpdfepubexeswfrtfwoffwoff2eotttfotficoflvpsxzsqlite
SVG isn't included as it requires the whole file to be read, but you can get it here.
PR welcome for additional commonly used file types.
License
MIT © Sindre Sorhus