filter_var + FILTER_VALIDATE_URL mode too restrictive for url parsing

[tjth]

Using the PHP function filter_var causes some URLs to be marked as invalid. One such example is any URL with an underscore in the subdomain. Please see https://stackoverflow.com/questions/39539468/php-filter-validate-url-not-finding-subdomains-with-underscore.

Suggestion: use parse_url with PHP_URL_HOST.

https://github.com/onelogin/php-saml/blob/master/lib/Saml2/Settings.php

[pitbulk]

Based on this, it seems not that simple

[fabpot]

See symfony/symfony#10467 (comment)