code: function nextId() {
      var maxId = 0;
      for (var i = 0; i < comments.length; i++) {
        var comment = comments[i];
        if (maxId < comment.id) {
          maxId = comment.id;
        }
      }
      return maxId + 1;
    }
docs: /*
  this.findByUsernameAndIsPrivate = function(username, isPrivate, cb) {
  for (var i = 0; i < users.length; i++) {
  var user = users[i];
  if (user.username  == username) {
  models.Post.countByUserIdAndIsPrivate(user.id, isPrivate, function(err, count) {
  user.posts = count;
  cb(null, setRelation([user])[0]);
  });
  break;
  }
  }
  };
  
  this.findByUsername = function(username, cb) {
  for (var i = 0; i < users.length; i++) {
  var user = users[i];
  if (user.username  == username) {
  models.Post.countByUserId(user.id, function(err, count) {
  user.posts = count;
  cb(null, setRelation([user])[0]);
  });
  break;
  }
  }
  };