Work around with url with params. for routing. Found in node-restify.

realizeUrl.js

/**
 * Returns a string representation of a URL pattern , 
 * with its parameters filled in by the passed hash.
 *
 * If a key is not found in the hash for a param, it is left alone.
 *
 * @param {Object} a hash of parameter names to values for substitution.
 */
function realizeUrl(pattern, params) {
    var p = pattern.replace(/\/:([^/]+)/g, function (match, k) {
        return (params.hasOwnProperty(k) ? '/' + params[k] : match);
    });

    // return (require('./utils').sanitizePath(p));

    // cleans up sloppy URL paths, like /foo////bar/// to /foo/bar.
    // ** copy from sanitizePath() **
  
    // be nice like apache and strip out any //my//foo//bar///blah
    p = p.replace(/\/\/+/g, '/');

    // kill a trailing '/'
    if (p.lastIndexOf('/') === (p.length - 1) && p.length > 1)
        p = p.substr(0, p.length - 1);

    return (p);
}