express3-dynamic-helpers-patch/index.js

Dynamic helpers monkey patch for express 3

'use strict';

// express 3.x response patch for dynamicHelpers support
var response = require('express').response,
  render = response.render;


module.exports = function(app) {
  // add dynamicHelpers function to app object
  app.dynamicHelpers = function(helpers) {
    app._dynamicHelpers = app._dynamicHelpers || {};
    for (var key in helpers) {
      if (helpers.hasOwnProperty(key)) {
        app._dynamicHelpers[key] = helpers[key];
      }
    }
  };
};

// patch render function
response.render = function() {
  var locals = {},
    dynamicHelpers = this.app._dynamicHelpers;

  if (dynamicHelpers) {
    for (var key in dynamicHelpers) {
      // call every helper and sign result to locals
      locals[key] = dynamicHelpers[key].call(this.app, this.req, this);
    }
  }

  this.locals(locals);
  render.apply(this, arguments);
};