Laravel - Validation - Basic Usage Of Mime Rule
'photo' => 'mimes:jpg,bmp,png'
Even though you only need to specify the extensions, this rule actually validates the MIME type of the file by reading the file's contents and guessing its MIME type. A full listing of MIME types and their corresponding extensions may be found at the following location:
https://svn.apache.org/repos/asf/httpd/httpd/trunk/docs/conf/mime.types