mimesniff
v1.1.1
Published
Sniff MIME types in browser
Readme
MIME Sniffing for the Browser
Do you not trust your the mime type determined by your browser, you shouldn't. Most browsers will take a
file's extension to determine MIME type. Using getMIMEType(file) will try sniff the file type:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>MIME test</title>
<script src="index.js"></script>
</head>
<body>
<input id="file" type="file" />
<ol></ol>
<script type="text/javascript">
document.getElementById('file').addEventListener('change', (e) => {
for (let file of e.srcElement.files) {
const li = document.createElement('li');
getMIMEType(file)
.then(
text => li.innerText = text,
text => li.innerText = `${error} -> I'll use the browser supplied one: ${file.type}`
)
.then(() => document.querySelector('ol').appendChild(li));
}
});
</script>
</body>
</html>Can sniff:
| Category | Type | |----------|------| | audio | aiff | | audio | mpeg | | application | ogg | | audio | midi | | video | avi | | audio | wave | | image | bmp | | image | gif | | image | gif | | image | webp | | image | png | | image | jpeg | | application | x-gzip | | application | zip | | application | x-rar-compressed | | application | postscript | | application | pdf |
Develop
Want to add support for more types? Take a look at the MIME Sniffing living standard.