Ensure that a well-formed url matches a domain and it's subdomains, but don't allow userInfo

domain-match-regex.js

// Modified from https://github.com/google/closure-library/blob/7818ff7dc0b53555a7fb3c3427e6761e88bde3a2/closure/goog/uri/utils.js#L189-L208 
new RegExp(
    '^' +                             // Anchor against the entire string.
    'https?:\\/\\/' +                 // scheme
    '(?![^\\\\\\/?#]*@)' +            // userInfo disallowed
    '(?:(?:[^\\\\\\/?#\\.]+?)\\.)*' + // subdomain
    'mydomain.com' +                  // domain
    '(?::[0-9]+)?' +                  // port
    '(?=[\\\\\\/?#]|$)'               // authority-terminating character.
);