# Namespace: `Router` [@jupyterlite/server](jupyterlite_server.md).Router A namespace for Router statics. ## Type Aliases ### `Callback` Ƭ **`Callback`**: (`req`: [`IRequest`](../interfaces/jupyterlite_server.Router.IRequest.md), ...`args`: `string`[]) => `Promise`<`Response`\> #### Type declaration > > (`req`, `...args`): `Promise`<`Response`\> The Callback type. ##### Parameters | Name | Type | | :------ | :------ | | `req` | [`IRequest`](../interfaces/jupyterlite_server.Router.IRequest.md) | | `...args` | `string`[] | ##### Returns `Promise`<`Response`\> #### Defined in [packages/server/src/router.ts:135](https://github.com/jupyterlite/jupyterlite/blob/999c7f0/packages/server/src/router.ts#L135) ### `Method` Ƭ **`Method`**: ``"GET"`` \| ``"PUT"`` \| ``"POST"`` \| ``"PATCH"`` \| ``"DELETE"`` The Method type. #### Defined in [packages/server/src/router.ts:140](https://github.com/jupyterlite/jupyterlite/blob/999c7f0/packages/server/src/router.ts#L140)