Change URL in a hapi onRequest ext point.

onreq.js

// wherever you're setting up your server, this was within a register method for a plugin:

plugin.select('api').ext('onRequest', internals.onRequest);

//somewhere else in that file or whatever

var onRequest = function (request, next) {

    request.setUrl(exports.rewriteUrl(request.raw.req.url));
    next();
};

var rewriteUrl = function (requestUrl) {

    /**
     * magic to change request url
    */

    return requestUrl;
};

For version 16:
Line 10:
return next.continue();