docs: function getController (method, path, role) {
      // if path does not exist return
      if (!this.paths[path]) {
          return
      }
      // if method does not exist return
      if (!this.paths[path][method]) {
          return
      }
      // set role to default if not defined
      if (role === undefined) {
          role = 'all'
      }
      // find controller matching role
      return _.find(this.paths[path][method], controller => {
          return controller.role === role ? true : false
      })
  }