mobx-keystone/dist/types/action/middleware.d.ts

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

import { ActionContext } from './context';
/**
 * An action middleware.
 */
export interface ActionMiddleware {
    /**
     * Subtree root object (object and child objects) this middleware will run for.
     * This target "filter" will be run before the custom filter.
     */
    readonly subtreeRoot: object;
    /**
     * A filter function to decide if an action middleware function should be run or not.
     */
    filter?: (ctx: ActionContext) => boolean;
    /**
     * An action middleware function.
     * Rember to `return next()` if you want to continue the action or throw if you want to cancel it.
     */
    middleware: (ctx: ActionContext, next: () => any) => any;
}
/**
 * The disposer of an action middleware.
 */
export type ActionMiddlewareDisposer = () => void;
/**
 * Adds a global action middleware to be run when an action is performed.
 * It is usually preferable to use `onActionMiddleware` instead to limit it to a given tree and only to topmost level actions
 * or `actionTrackingMiddleware` for a simplified middleware.
 *
 * @param mware Action middleware to be run.
 * @returns A disposer to cancel the middleware. Note that if you don't plan to do an early disposal of the middleware
 * calling this function becomes optional.
 */
export declare function addActionMiddleware(mware: ActionMiddleware): ActionMiddlewareDisposer;