mobx-keystone/dist/types/actionMiddlewares/readonlyMiddleware.d.ts

A MobX powered state management solution based on data trees with first class support for TypeScript, snapshots, patches and much more

import { ActionMiddlewareDisposer } from '../action/middleware';
/**
 * Return type for readonly middleware.
 */
export interface ReadonlyMiddlewareReturn {
    allowWrite: <R>(fn: () => R) => R;
    dispose: ActionMiddlewareDisposer;
}
/**
 * Attaches an action middleware that will throw when any action is started
 * over the node or any of the child nodes, thus effectively making the subtree
 * readonly.
 *
 * It will return an object with a `dispose` function to remove the middleware and a `allowWrite` function
 * that will allow actions to be started inside the provided code block.
 *
 * Example:
 * ```ts
 * // given a model instance named todo
 * const { dispose, allowWrite } = readonlyMiddleware(todo)
 *
 * // this will throw
 * todo.setDone(false)
 * await todo.setDoneAsync(false)
 *
 * // this will work
 * allowWrite(() => todo.setDone(false))
 * // note: for async always use one action invocation per allowWrite!
 * await allowWrite(() => todo.setDoneAsync(false))
 * ```
 *
 * @param subtreeRoot Subtree root target object.
 * @returns An object with the middleware disposer (`dispose`) and a `allowWrite` function.
 */
export declare function readonlyMiddleware(subtreeRoot: object): ReadonlyMiddlewareReturn;