ngrx-handlers/fesm2015/ngrx-handlers.js

NgRx Plugin for Generating Actions and Reducer Based on the Handler Map

import { __rest } from 'tslib';
import { createAction, props } from '@ngrx/store';

/**
 * Generates a map of action creators and reducer function based on the initial state, source and handler map.
 *
 * @param initialState An initial state of the reducer function.
 * @param source A source of the actions creators.
 * @param handlers A map where the keys are action events and the values are case reducers.
 * @returns A tuple of action creator map and the reducer function.
 *
 * @example
 * // movies.state.ts
 * interface MoviesState {
 *   movies: Movie[];
 *   selectedMovieId: number | null;
 *   searchTerm: string;
 *   loading: boolean;
 * }
 *
 * const initMoviesState: MoviesState = {
 *   movies: [],
 *   selectedMovieId: null,
 *   searchTerm: '',
 *   loading: false,
 * };
 *
 * // movies-page.handlers.ts
 * const [moviesPageActions, moviesPageReducer] = combineHandlers(initMoviesState, 'moviesPage', {
 *   updateSelectedMovieId: (state, { selectedMovieId }: { selectedMovieId: number }) => ({
 *     ...state,
 *     selectedMovieId,
 *   }),
 *   updateSearchTerm: (state, { searchTerm }: { searchTerm: string }) => ({
 *     ...state,
 *     searchTerm,
 *   }),
 * });
 *
 * // movies-effects.handlers.ts
 * const [moviesEffectsActions, moviesEffectsReducer] = combineHandlers(
 *   initMoviesState,
 *   'moviesEffects',
 *   {
 *     fetchMovies: state => ({ ...state, loading: true }),
 *     fetchMoviesSuccess: (state, { movies }: { movies: Movie[] }) => ({
 *       ...state,
 *       movies,
 *       loading: false,
 *     }),
 *     fetchMoviesError: state => ({ ...state, movies: [], loading: false }),
 *   },
 * );
 *
 * @see mergeReducers
 */
function combineHandlers(initialState, source, handlers) {
    return [createActions(source, handlers), createReducer(initialState, source, handlers)];
}
/**
 * Creates a plain case reducer.
 *
 * @returns A plain case reducer.
 *
 * @example
 * const [moviesPageActions, moviesPageReducer] = combineHandlers(initMoviesState, 'moviesPage', {
 *   showCreateMovieDialog: plain(),
 * });
 *
 * @see combineHandlers
 */
function plain() {
    return state => state;
}
/**
 * Creates a plain case reducer with the payload.
 *
 * @returns A plain case reducer with the payload.
 *
 * @example
 * const [moviesPageActions, moviesPageReducer] = combineHandlers(initMoviesState, 'moviesPage', {
 *   createMovie: withPayload<{ movie: Movie }>(),
 * });
 *
 * @see combineHandlers
 */
function withPayload() {
    return plain();
}
function createActions(source, handlers) {
    return Object.keys(handlers).reduce((actionMap, event) => (Object.assign(Object.assign({}, actionMap), { [event]: createAction(toActionType(source, event), props()) })), {});
}
function createReducer(initialState, source, handlers) {
    return (state = initialState, action) => {
        const { type } = action, payload = __rest(action, ["type"]);
        const reducer = source === toSource(type) ? handlers[toEvent(type)] : null;
        return reducer ? reducer(state, payload) : state;
    };
}
function toActionType(source, event) {
    return `[${source}] ${event}`;
}
function toSource(actionType) {
    return actionType.slice(1).split(']').shift();
}
function toEvent(actionType) {
    return actionType.split('] ').pop();
}

/**
 * Merges the array of reducers into one.
 *
 * @param reducers An array of reducers for the same state slice.
 * @returns A reducer merged from the provided reducers.
 *
 * @example
 * // movies.reducer.ts
 * const moviesReducer = mergeReducers(moviesPageReducer, moviesEffectsReducer);
 *
 * // movies.module.ts
 * \@NgModule({
 *   imports: [StoreModule.forFeature('movies', moviesReducer)],
 * })
 * export class MoviesModule {}
 *
 * @see combineHandlers
 */
function mergeReducers(...reducers) {
    return (state, action) => {
        const reducer = reducers.find(r => r(state, action) !== state);
        return reducer ? reducer(state, action) : state;
    };
}

/**
 * Generated bundle index. Do not edit.
 */

export { combineHandlers, mergeReducers, plain, withPayload };
//# sourceMappingURL=ngrx-handlers.js.map