How to do Server side validation using Uploadify plugin?

Question

I would like to do below validations for single file uploaded using jQuery Uploadify plugin.

1. Check for the file type .jpg, .png & .gif
2. Check for the file size maximum 2MB only

I have done this through fileExt & sizeLimit options, but as the plugin developer says, one can easily bypass the fileExt validation & server side validation is recommended.

I want to do this using PHP server side scripting language.

I have already checked the documentation of the plugin & nothing helpful found there. Can someone please suggest how to do this ?

Thanks in advance.

Answer 1

I would recommend using the filesize and exif_imagetype functions to assess the file. The following should point you in the right direction:

$up_file = "file_the_user_uploaded";
$two_mb = 2097152;
if (filesize($up_file) < $two_mb) {
    if (exif_imagetype($up_file) > 0 && exif_imagetype($up_file) < 4) {
        // the file is .gif, .jpg, or .png and less than 2MB
        // do something to approve the file upload
    }
}

Note that the filesize() function in PHP returns the size in bytes, thus, the file should be less than $two_mb bytes. Also, the exif_imagetype() returns an integer code mapping to the MIME type of the uploaded image: 1, 2, 3, being .gif, .jpg, and .png respectively.