jsgi proxy

var
  Q          = require('promised-io/promise'),
  when       = Q.when,
  HttpClient = require('promised-io/http-client').Client,
  sys        = require('sys');

exports.proxy = function(from, to, nextApp) {
  var
    client = new HttpClient();
    
  if (from.constructor === String) {
    from = new RegExp('^' + from);
  }
  
  return function(jsgiReq) {
    var proxyReq;
    console.log("PathInfo: " + jsgiReq.pathInfo);
    
    if (jsgiReq.pathInfo.match(from)) {
      proxyReq = {};
      for (var key in jsgiReq) {
        proxyReq[key] = jsgiReq[key];
      }
      proxyReq.url = to;
      
      console.log('Request to '+sys.inspect(proxyReq));
      return when(client.request(proxyReq), function(resp) {
        return resp;
      });
    } else {
      nextApp(jsgiReq);
    }
  };
}