修剪斜线和时期的网址

Question

I am trying to validate a URL when i am sending it through a form, I want to make sure it begins with either https or http, has at least one period, and then doesn't have a period or trailing slash at the end. I have achieved the http and period bit through the use of regex, however I can't seem to work out how to trim the url if it has either . , ./ , /. or / I use rtrim but it only works if it finds the single characters, is there a way to remove both of them if appear?

Here is my code:

//update the canonical url
        $canonical_url = $_POST ['canonical_url'];
        $valid_url =  preg_match('/^(http[s]?:\/\/)?([\da-z\.-]+)\.([a-z\.]{2,6})([\/\w \.-]*)*\/?$/', $canonical_url );
        if ($valid_url) {
            $removed_period = rtrim($canonical_url, '.');
            $final_canonical = rtrim($removed_period, '/');
        }

Answer 1

You could use filter_var to validate your URL and preg_replace to trim the trailing ., ./, /. or /, if any.

$canonical_url = $_POST['canonical_url'];
if (filter_var($canonical_url, FILTER_VALIDATE_URL, FILTER_FLAG_SCHEME_REQUIRED)) {
    $final_canonical = preg_replace('/(\.|\.\/|\/\.|\/)$/', '', $canonical_url);
}

Note that FILTER_VALIDATE_URL allows any RFC 2396 compliant URI, so if you only admit http/https, you could add:

if(filter_var(…) && strpos($canonical_url, 'http') !== false) {…}