1/**
 2 * Initialization middleware, exposing the
 3 * request and response to eachother, as well
 4 * as defaulting the X-Powered-By header field.
 5 *
 6 * @param {Function} app
 7 * @return {Function}
 8 * @api private
 9 */
10
11exports.init = function(app){
12  return function expressInit(req, res, next){
13    if (app.enabled('x-powered-by')) res.setHeader('X-Powered-By', 'Express');
14    req.res = res;
15    res.req = req;
16    req.next = next;
17
18    req.__proto__ = app.request;
19    res.__proto__ = app.response;
20
21    res.locals = res.locals || Object.create(null);
22
23    next();
24  };
25};
26