MIME Type extraction and validation by RFC 2045, RFC 833

mime-type-extract-rfc2045.js

// Pattern (RFC 833, RFC 2045, https://www.ietf.org/rfc/rfc2045.txt)
// Tested against 1200~ types @ http://www.iana.org/assignments/media-types/media-types.xhtml
const pattern = /^(text|image|audio|video|application+)\/([a-zA-Z\d\+\-\.\:\_]+)$/;
 
// Tests
pattern.test("application/x-bzip2");
pattern.test("application/vnd.amazon34.ebook");
pattern.test("application/octet-stream");
 
// Match
"application/x-bzip2".match(pattern);
 
// Output
{
  0:"application/x-bzip2"
  1:"application"
  2:"x-bzip2"
  index:0
  input:"application/x-bzip2"
  length:3
}