ngrx 8+ with immer and support for on() within reducer

ngrx8_with_immer.ts

import {createReducer} from '@ngrx/store';
import {on} from "@ngrx/store";
import produce, {Draft} from "immer";

export const initialUserState: IUserState = {
    knownUsers: [user1, user2],
    selectedUser: null,
    scenes: null
};

export function produceOn<Type extends string, C extends FunctionWithParametersType<any, object>, State>(
    actionType: ActionCreator<Type, C>,
    callback: (draft: Draft<State>, action: ActionType<ActionCreator<Type, C>>) => any,
) {return on(actionType, (state: State, action): State => produce(state, (draft) => callback(draft, action)));}
      
export const loadRequest = createAction('[Scenes API] Scene Load Request', props<{ businessId: BusinessId }>());
export const loadSuccess = createAction('[Scenes API] Scene Load Success', props<{ scenes: List<SceneModel> }>());

// ngrx 8+ with immer and support for on() within reducer
      
const featureReducer = createReducer(
    initialUserState,
    produceOn(loadSuccess, (draft, action) => {
        draft.scenes = {myList: [1,2,3]};
    }),
    produceOn(loadFailure, (draft, action) => {
        draft.scenes = {myList: []};
        console.log('error loading...');
    })
);