@ngrx/store combine multiple reducers from feature module

Question

I am currently working on a simple test app to learn more about the @ngrx/store. I have a module called TrainingModule which should store some exercises and more information. T

Answer 1

Your setup is almost correct.

In the createFeatureSelector function you declare a feature key in the root of the store, 'exercises' in the example. So, you are going to select store.exercises.exercises.id for example and feature selector is just a shortcut to store.exercises.

However, in the StoreModule.forFeature('training', trainingReducers) call you defined 'training' as the root key for your feature module.

The correct setup could look like this:

export const featureReducersMap = {
  exercise: exerciseReducer,
  anyOtherKey: anyOtherReducer
};

StoreModule.forFeature('myFeatureModule', featureReducersMap);

export interface FeatureState{
  exercise: string;
  anyOtherKey: number;
}

Then write selectors like:

export const featureSelector = createFeatureSelector('myFeatureModule');

export const exerciseSelector = createSelector(
  featureSelector,
  (state: FeatureState) => state.exercise
);

It is recommended to store the feature key in the variable instead of hardcoding it.