text: var express = require('express');
  var router = express.Router();
  var mongoose = require('mongoose');
  
  var Comment = mongoose.model('Comment');
  
  /* GET edit page by ID . */
  router.get('/:commentId', function(req, res, next) {
      var commentId = req.params.commentId;
      res.render('edit', { title: 'Express', id: commentId });
      //res.send('respond with a resource');
  });
  
  router.param('commentId', function(req, res, next, commentId) {
      var query = Comment.findById(commentId);
  
      query.exec(function (err, comment){
          if (err) { return next(err); }
          if (!comment) { return next(new Error('can\'t find comment')); }
  
          req.comment = comment;
          return next();
      });
  });
  
  module.exports = router;