NgRxLite

A small Angular state mangement based on NgRx ComponentStore, with some benefits 😎

Synopsis

The current @ngrx/component-store implementation works with its own isolated store. Unfortunately, there is no connection to the global @ngrx/store or the @ngrx/store-devtools.

This Library connects your @ngrx/component-store with the @ngrx/store to share and debug the @ngrx/actions and store.

Benefits

• 🤝 same API as @ngrx/component-store with optional parameters
• ⏱ fast and easy creation of a dynamic Redux store
• ⏳ optional integrated loading state for effects
• 🤯 debuging of application state across different routes
• ⚒️ Redux DevTools support for NgRxLite ComponentsStore for
  • patchState
  • setState
  • createdLoadingEffects
• 💽 supports session storage and local storage
• 🏘 freedom to decide where the store is located: root, module or in the component scope
• 🔛 share the state changes and actions in the NgRx store
• 📑 store the form data for persistance and debugging
• 👂 create effects for global storage
• ✍️ write the tests is much easier

• 👩‍💻 checkout the sample app
• ▶️ Play with a Demo
• 📖 read the docs

Install

Yarn

yarn add @ngrx/store @ngrx/effects @ngrx/component-store @ngrx/store-devtools @gernsdorfer/ngrx-lite

NPM

npm install @ngrx/store @ngrx/effects @ngrx/component-store @ngrx/store-devtools @gernsdorfer/ngrx-lite

Usage

1. import the StoreModule from NgRx to the root module

@NgModule({
  // ...
  imports: [StoreModule.forRoot({})]
// ...

2. create the store with the same API as @ngrx/component-store

export interface MyState {
  counter: number;
}

@Component({
  selector: 'my-component',
  template: '<button (click)="load(\'test\')">',
})
class MyComponent implements OnDestroy {
  // create a componentStore
  private store = this.storeFactory.createComponentStore<MyState>({
    storeName: 'BASIC_COUNTER',
    defaultState: { counter: 0 },
  });
  // read the state
  public counterState$: Observable<MyState> = this.store.state$;

  constructor(private storeFactory: StoreFactory) {}

  increment(counter: number) {
    // patch your state
    this.store.patchState({ counter });
  }

  ngOnDestroy() {
    // destory the store
    this.store.ngOnDestroy();
  }
}

That's it 🥳

Features

DevTools support

Install and import ngrx/store-devtools und have all the features from the DevTools for your component store.

It's important to set the monitor property in your StoreDevtoolsOptions, otherwise a state import is not possible.

@NgModule({
  imports: [
    StoreDevtoolsModule.instrument({
      name: 'ngrx-lite-demo',
      maxAge: 25,
      logOnly: false,
      // set the monitor property here
      monitor: (state, action) => action,
    }),

  ],
})

Let's take a look at Redux DevTools and what happens in the example above.

Store is initialized

After the store is initialized you can find the store in the @ngrx/devtools.

Patch state

After patch state you see this in your Redux DevTools. It's possbile to define an custom action name for your patch/set state.

Router store

Import the RouterStoreModule into your main application to debug your state across all visited URLs. This module stores related URLs to the current store.

So it's possible to replay your state changes by revisiting the related url.

@NgModule({
  //...
  imports: [RouterStoreModule]
//...

Loading store

Create ComponentLoadingStore to set a Loader State while an Effect is running. You have the same API as createComponentStore with an extra method loadingEffect.

type State = LoadingStoreState<{ counter: number }, { message: string }>;

@Component({
  selector: 'my-app-basic-app',
  templateUrl: 'loading-effect.html',
})
export class LoadingEffectComponent implements OnDestroy {
  // create your loading store
  private store = this.storeFactory.createComponentLoadingStore<State['item'], State['error']>({
    storeName: 'LOADING_STORE',
  });

  // read the state
  public counterState$: Observable<State> = this.store.state$;

  // define your loadingEffect to change the state
  public increment = this.store.loadingEffect('increment', (counter: number = 0) => of(counter + 1));

  constructor(private storeFactory: StoreFactory) {}

  ngOnDestroy() {
    // destory the store
    this.counterStore.ngOnDestroy();
  }
}

Let's take a look at Redux DevTools and what happens in the example above.

Store is initialized

After the store is initialized you can find the store in the @ngrx/devtools.

Loader state isLoading changed

For a running Effect isLoading is true and you can show a spinner in your UI.

Effect successfully executed

After an effect was successfully executed the item key is updated.

Effect unsuccessfully executed

After an effect was unsuccessfully executed the error key contains the error.

Form Store

interface Product {
  name: string;
}

@Component({
  selector: 'my-app-basic-app',
  templateUrl: 'persist-form.html',
})
export class PersistFormComponent implements OnDestroy {
  productForm = new FormGroup({
    name: new FormControl('', [Validators.required]),
    lastName: new FormControl('', [Validators.required]),
  });
  private store = this.storeFactory.createFormComponentStore<Product>({
    storeName: 'PRODUCT_FORM',
    plugins: {
      storage: 'sessionStoragePlugin',
    },
    formGroup: this.productForm,
  });
}

Session/Local Storage

Register Session/Locale storage service

1. Register Session/Locale storage in your root module

@NgModule({
  // ...
  providers: [
    {provide: SessionStoragePlugin, useValue: sessionStoragePlugin},
    {provide: LocalStoragePlugin, useValue: localStoragePlugin}
  ]
  // ...
})

1. Create new store with a session storage sync option

class MyClass {
  private store = this.storeFactory.createComponentStore<{ counter: number }>({
    storeName: 'SESSION_COUNTER',
    defaultState: {
      counter: 0,
    },
    plugins: {
      storage: 'sessionStoragePlugin',
    },
  });
}

Create Effects

For Using createEffect, please install @ngrx/effects and import EffectsModule.forRoot([]) in your root module

export const resetAction = createAction('reset');

class MyClass {
  private store = this.storeFactory.createComponentStore<{ counter: number }>({
    storeName: 'SESSION_COUNTER',
    defaultState: {
      counter: 0,
    },
  });

  myEffect = this.store.createEffect((action) =>
    action.pipe(
      ofType(resetAction),
      tap(() => console.log('do sth.')),
    ),
  );
}

Listen on actions

listen on custom actions to execute your business logic

export interface MyState {
  counter: number;
}
export const resetAction = createAction('reset');

@Injectable()
export class MyStore implements OnDestroy {
  private storeFactory = inject(StoreFactory);
  private store = this.storeFactory.createComponentStore<MyState>({
    storeName: 'BASIC_COUNTER',
    defaultState: { counter: 0 },
  });

  onReset = this.store.onActions([resetAction]);
}

export class AppComponent {
  private myStore = inject(MyStore);
  resetEffect = this.myStore.onReset(() => console.log('Reset was triggered'));
}

Testing

Import storeTestingFactory and write your tests. A minimal example can be found here .

TestBed.configureTestingModule({
  //...
  providers: [storeTestingFactory()],
  //..
});