Tag: Angular reducers example

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I’m the manager of a restaurant kitchen. Each dish I prepare is like a component in my Angular application, with its own set of ingredients—just like state in the app. In this kitchen, managing all these ingredients efficiently is crucial to ensuring every dish is perfect and goes out on time.

In this analogy, the pantry is my centralized store, like NgRx in Angular. It’s where all my ingredients (or state) are stored. Instead of having separate mini-pantries for each dish, I use this central pantry to keep everything organized. This way, I know exactly where to find what I need, just like I would access state from a central store.

Now, imagine each ingredient has a label that tells me the last time it was used and its quantity. This is like using selectors in Angular, which help me efficiently retrieve only the necessary state without rummaging through the entire pantry. It saves me time and ensures I’m always using fresh ingredients.

When a new order comes in, I write it down on a ticket—my action. This ticket travels to the head chef, who decides how to adjust the pantry’s inventory. This is akin to reducers in Angular, which handle actions to update the state. By having this process in place, I maintain consistency and ensure no ingredient is overused or forgotten.

Sometimes, I have to make special sauces or desserts that require complex preparation. For these, I set up a separate workstation, much like using services in Angular to manage complicated state logic. This keeps my main cooking area clear and focused on the core dishes, ensuring efficiency and clarity.

In my kitchen, communication is key. Just as I rely on my team to know when to prepare appetizers or desserts, in Angular, I use effects to handle asynchronous operations, like fetching data from the server. This way, the main cooking line isn’t held up, and everything gets done smoothly and in sync.

By managing the kitchen this way, I ensure that every dish is a success, just as effectively managing state in Angular results in a smooth, responsive application. So, if you find this helpful, remember to give a like or share!

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Centralized Store (The Pantry)

In Angular, we often use NgRx to manage the centralized state. Here’s how we might set up a simple store:

// app.state.ts
export interface AppState {
  ingredients: string[];
}

// initial-state.ts
export const initialState: AppState = {
  ingredients: []
};

Actions (The Order Tickets)

Actions in NgRx are like the order tickets in the kitchen. They specify what needs to be done:

// ingredient.actions.ts
import { createAction, props } from '@ngrx/store';

export const addIngredient = createAction(
  '[Ingredient] Add Ingredient',
  props<{ ingredient: string }>()
);

Reducers (The Head Chef’s Decisions)

Reducers handle the actions and update the state accordingly:

// ingredient.reducer.ts
import { createReducer, on } from '@ngrx/store';
import { addIngredient } from './ingredient.actions';
import { initialState } from './initial-state';

const _ingredientReducer = createReducer(
  initialState,
  on(addIngredient, (state, { ingredient }) => ({
    ...state,
    ingredients: [...state.ingredients, ingredient]
  }))
);

export function ingredientReducer(state, action) {
  return _ingredientReducer(state, action);
}

Selectors (Labeling the Ingredients)

Selectors help fetch specific parts of the state efficiently:

// ingredient.selectors.ts
import { createSelector } from '@ngrx/store';

export const selectIngredients = (state: AppState) => state.ingredients;

Services and Effects (Special Workstations)

Services or effects handle complex logic, like fetching data:

// ingredient.effects.ts
import { Injectable } from '@angular/core';
import { Actions, ofType, createEffect } from '@ngrx/effects';
import { addIngredient } from './ingredient.actions';
import { tap } from 'rxjs/operators';

@Injectable()
export class IngredientEffects {
  addIngredient$ = createEffect(
    () =>
      this.actions$.pipe(
        ofType(addIngredient),
        tap(action => {
          console.log(`Added ingredient: ${action.ingredient}`);
        })
      ),
    { dispatch: false }
  );

  constructor(private actions$: Actions) {}
}

Key Takeaways

1. Centralized State Management: Like a well-organized pantry, a centralized store helps manage state efficiently across the application.
2. Actions and Reducers: Actions act as orders for change, while reducers decide how to execute those changes, ensuring consistency.
3. Selectors: These help retrieve only the necessary state, improving performance and maintainability.
4. Effects and Services: Manage complex logic and asynchronous operations without cluttering the main state management logic.

By managing state in this structured way, we ensure that our Angular application runs smoothly, much like a well-coordinated kitchen ensures timely and perfect dishes. I hope this sheds light on how to manage state effectively in Angular!