title: Adding custom properties to Express app and req. What's the best way?
body: <p>Am I shooting myself in the foot:</p>
  
  <p>I want to make config, core, and mean available on the app and req objects in my Express app.</p>
  
  <p>I'm using properties not in the 4.x API.  Anything I should know?</p>
  
  <p>Is there a problem with just adding them as properties?  </p>
  
  <pre><code>// express.js
  module.exports = function(db, config, meanModules) {
  
    var app = express();
  
    // ... 
  
    // Get mean-core
    var core = require('meanjs-core')(db, config);
  
    // Attach config, core, and modules to app    &lt;==== POSSIBLE FOOT SHOOTING
    app.config = config;
    app.core = core;
    app.mean = meanModules;
  
    // Middleware to adjust req
    app.use(function(req, res, next) {
      // Add config, core, and modules to all requests  &lt;==== POSSIBLE FOOT SHOOTING
      req.config = config;
      req.core = core;
      req.mean = meanModules;
      next();
    });
  
    // ...
  }
  </code></pre>