Get File Type by URL for a Remote File in WordPress

get-file-type-url-remote-file-wordpress.php

<?php

/**
 * Get the file mime type for a file by its URL.
 *
 * @param  $url The URL to the file.
 * @return      The file mime type or empty string on failure.
 */
function km_get_file_type_by_url( $url ) {

	$response  = wp_remote_get( $url );

	return wp_remote_retrieve_header( $response, 'content-type' );

}