code: function (fn) {
      if (fn.length === 1) {
        fn = _.wrap(fn, function(func, evt, callback) {
          func(evt);
          callback(null);
        });
      }
  
      this.publisher = fn;
  
      return this;
    }
docs: Inject function for event publishing.
  @param {Function} fn the function to be injected
  @returns {Eventstore}  to be able to chain...