How do I find the mime-type of a file with php?

Question

Ok, so I have an index.php file which has to process many different file types. how do I guess the filetype based on the REQUEST_URI.

If I request http://site/image.jpg, and all requests redirect through index.php, which looks like this

<?php
   include('/www/site'.$_SERVER['REQUEST_URI']);
?>

How would I make that work correctly?

Should I test based on the extension of the file requested, or is there a way to get the filetype?

Answer 1

If you are sure you're only ever working with images, you can check out the getimagesize() PHP function, which attempts to return the image mime-type.

If you don't mind external dependencies, you can also check out the excellent getID3 library which can determine the mime-type of many different file types.

Lastly, you can check out the mime_content_type() function - but it has been deprecated for the Fileinfo PECL extension.

Answer 2

I haven't used it, but there's a PECL extension for getting a file's mimetype. The official documentation for it is in the manual.

Depending on your purposes, a file extension can be ok, but it's not incredibly reliable since it's so easily changed.

Answer 3

According to the php manual, the finfo-file function is best way to do this. However, you will need to install the FileInfo PECL extension.

If the extension is not an option, you can use the outdated mime_content_type function.

Answer 4

if you're only dealing with images you can use the [getimagesize()][1] function which contains all sorts of info about the image, including the type.

A more general approach would be to use the FileInfo extension from PECL. The PHP documentation for this extension can be found at: http://us.php.net/manual/en/ref.fileinfo.php

Some people have serious complaints about that extension... so if you run into serious issues or cannot install the extension for some reason you might wanna check out the depricated function mime_content_type()

Answer 5

mime_content_type() is deprecated, so you won't be able to count on it working in the future. There is a "fileinfo" PECL extension, but I haven't heard good things about it.

If you are running on a *nix server, you can do the following, which has worked fine for me:

$file = escapeshellarg( $filename );

$mime = shell_exec("file -bi " . $file);

$filename should probably include the absolute path.