code: function(query) {
          var self = this;
          return Q.ninvoke(fs, 'readdir', path.join(this.backend.options.path, this.name))
              .then(function(files) {
                  return Q.all(files.map(function(f) {
                      return self.get(f);
                  }));
              })
              .then(function(vals) {
                  return _.query(vals, query);
              });
      }
docs: Execute RQL query