Tag: Angular

How to organize large angular project structure to scale and maintain
When working on Angular projects, following best practices for project organization, code structure, and architecture is crucial for maintaining scalability, readability, and maintainability. In this article, we will explore a set of best practices that can help you streamline your Angular projects and ensure a successful development process.

Best project structure bellow for any generic project
```
∇ app
    ∇ core
         ∇ guards
              auth.guard.ts
              module-import.guard.ts
              no-auth.guard.ts
         ∇ interceptor
              token.interceptor.ts
              error.interceptor.ts
         ∇ services
              service-a.service.ts
              service-b.service.ts
         ∇ components
              ∇ navbar
                    navbar.component.html|scss|ts
              ∇ page-not-found
                    page-not-found.component.html|scss|ts
         ∇ constants
              constant-a.ts
              constant-b.ts
         ∇ enums
              enum-a.ts
              enum-b.ts
         ∇ models
              model-a.ts
              model-b.ts
         ∇ utils
              common-functions.ts
    ∇ features
         ∇ feature-a
              ∇ components
                    ∇ scoped-shared-component-a
                            scoped-shared-component-a.component.html|scss|ts
                    ∇ scope-shared-component-b
                            scoped-shared-component-b.component.html|scss|ts
              ∇ pages
                   ∇ page-a
                        page-a.component.html|scss|ts
                   ∇ page-b
                        page-b.component.html|scss|ts
              ∇ models
                    scoped-model-a.model.ts
                    scoped-model-b.model.ts
              ∇ services
                    scoped-service-a.service.ts
                    scoped-service-b.service.ts
              feature-a-routing.module.ts
              feature-a.module.ts
              feature-a.component.html|scss|ts
    ∇ shared
         ∇ components
              ∇ shared-button
                   shared-button.component.html|scss|ts
         ∇ directives
              shared-directive.ts
         ∇ pipes
              shared-pipe.ts
         shared.module.ts
    styles.scss
    ▽ styles
        app-loading.scss
        company-colors.scss
        spinners.scss
        variables.scss
    ▽ assets
        ▽ i18n
            lang-a.json
            lang-b.json
        ▽ images
            image-a.svg
            image-b.svg
        ▽ static
            structure-a.json
            structure-b.json
        ▽ icons
            custom-icon-a.svg
            custom-icon-b.svg
```
Structure explanation

1. Project Structure

A well-organized project structure is the foundation of a successful Angular application. Consider adopting the following structure:
- src: All application code goes here.
  - app: The root module and core application components.
    
    core: Singleton services, interceptors, guards, enums, constants, and utilities.
    
    shared: SharedModule containing reusable components, directives, and pipes.
    
    features: Feature modules, each representing a distinct application feature.
  - assets: Media files, fonts, and other static assets.
  - styles: Global styles and mixins for consistent theming.
  - environments: Configuration settings for different environments.
2. App Module

The root AppModule should be kept lean and focused. It’s the entry point of the application and should be responsible for bootstrapping the app and importing necessary modules. Avoid cluttering it with too many declarations.

3. Core Module

The CoreModule serves as the central module for root-scoped services, static components, and other singletons. It should only be loaded once at runtime and should not be lazily loaded. Use a module-import-guard to prevent re-importing it.

4. Shared Module

The SharedModule is responsible for housing reusable components, directives, and pipes. It should not have dependencies on other modules in the application and can significantly aid in reducing bundle size when using lazy loading.

Standalone Component

From angular 14 new feature introduced in angular where we don’t need to create a share module to reuse the components Read more on standalone component

Standalone component

5. Feature Modules

Feature modules encapsulate specific functionality of your application. Each feature module should be in its own folder and should depend on the SharedModule for reusability. Consider lazy loading feature modules to improve application performance.

6. Lazy Loading

Lazy loading modules can significantly improve the initial load time of your application. Use lazy loading for feature modules that aren’t required immediately on application startup.

7. Styles and Theming

Organize your styles into separate files based on their functionality. Use mixins and CSS functions to encapsulate styles. Consider theming your application for a consistent and appealing user experience.

8. State Management

Choose an appropriate state management solution based on the complexity of your application. Options include NgRx, RxJS, and other third-party libraries. Follow established patterns like Flux or Redux for better state management. Must to read about state management here.

9. Testing

Write comprehensive unit tests and end-to-end tests using tools like Jasmine, Karma, and Protractor. Adopt test-driven development (TDD) practices to ensure code quality and prevent regressions.

10. Documentation

Maintain clear and concise documentation for your Angular project. Use tools like Compodoc to generate comprehensive documentation for your components, modules, and services.

Conclusion

By adhering to these best practices, you can create well-structured, maintainable, and scalable Angular projects. Keep in mind that every project is unique, so feel free to adapt these practices to suit your specific needs. Following these guidelines will contribute to a smoother development process and a successful Angular application.

Remember, it’s important to write an original article that reflects your own insights and experiences. If you have any questions or need assistance with specific sections, feel free to ask!
August 15, 2023
Understanding power of Standalone component and How to use the standalone component in Angular
Angular 14 brings a remarkable new feature known as “Standalone Components” that revolutionizes the way developers build and reuse components within their applications. These standalone components are independent of any Angular module, offering a seamless way to create modular and reusable UI elements. In this blog, we’ll explore the concept of standalone components and how they can be utilized to pass dynamic values and achieve diverse outcomes with ease.

Understanding Standalone Components

Traditionally, Angular components are part of modules defined using the @NgModule decorator. These components can be used within the same module or other modules by importing the respective module. However, standalone components break free from this constraint. They can be created with the help of the Angular CLI’s --standalone flag, which generates components that are not bound to any specific module.

Creating a Standalone Component

To create a standalone component, let’s say a component named MyComponent, you can use the following Angular CLI command:
```
ng g c my-component --standalone
```
Upon generating the component, the @Component decorator in the generated my-component.ts file will have a new property standalone: true to indicate that it is a standalone component.
```
import { Component } from '@angular/core';
import { CommonModule } from '@angular/common';
import { FormsModule } from '@angular/forms';

@Component({
  selector: 'app-my-component',
  template: `<p>My standalone component</p>`,
  imports: [CommonModule, FormsModule],
  standalone: true
})
export class MyComponent {}
```
Utilizing Standalone Components

Once you have a standalone component created, you can use it anywhere within your Angular project. To do so, simply import the standalone component into the file where you want to use it and include its selector in your template. The standalone component acts just like any other Angular component, offering seamless integration and reusability.

Input Decorator for Dynamic Values

One of the most significant advantages of standalone components is the ability to pass dynamic values through the use of input decorators. In the given example below, the app-my-component selector has three input properties: title, visible, and color.
```
<app-my-component [title]="appTitle" [visible]="true" [color]="app-status"></app-my-component>
```
The input decorator @Input() in the standalone component’s class allows you to bind these properties and receive data from its parent component.
```
import { Component, Input } from '@angular/core';

@Component({
  selector: 'app-my-component',
  template: `<p>My standalone component</p>`,
})
export class MyComponent {
  @Input() title: string;
  @Input() visible: boolean;
  @Input() color: string;
}
```
By leveraging input properties, you can dynamically pass data from any parent component and influence the behavior and appearance of the standalone component accordingly.

Conclusion

Angular 14’s standalone components offer a groundbreaking approach to building modular and reusable UI elements. By creating components that are not bound to specific modules, developers can simplify development processes and enhance code reusability. Furthermore, the input decorator enables dynamic data binding, allowing for versatile and flexible component behaviors.

Whether you are building large-scale applications or smaller projects, standalone components prove to be a valuable tool in your Angular development arsenal. Embrace this feature to create cleaner, more maintainable, and efficient code while delivering outstanding user experiences. Happy coding!
July 29, 2023
State Management in Angular using Ngrx
In Angular, we use state management libraries like ngrx to handle complex data flows in large applications. ngrx is a reactive state management library based on the Redux pattern, which provides a way to manage state changes in Angular applications. It uses Observables, Actions, Reducers, and Effects to manage state changes.

In this blog, we will discuss the steps to use ngrx in an Angular application and understand its flow.
Step 1: Install ngrx

First, we need to install ngrx using the npm package manager.
```
npm install @ngrx/store --save
```
Step 2: Define the state

The state is the data that we want to manage in the application. We define the state using an interface in a separate file. For example, we can define a state interface for a counter application as follows:

typescript
export interface CounterState {
count: number;
}

Step 3: Define the actions

Actions describe the changes that occur in the application. We define actions using an enum in a separate file. For example, we can define actions for a counter application as follows:

typescript
import { createAction } from ‘@ngrx/store’;

export enum CounterActionTypes {
Increment = ‘[Counter] Increment’,
Decrement = ‘[Counter] Decrement’,
}

export const increment = createAction(
CounterActionTypes.Increment
);

export const decrement = createAction(
CounterActionTypes.Decrement
);

Step 4: Define the reducers

Reducers specify how the application state changes in response to actions. We define reducers in a separate file. For example, we can define reducers for a counter application as follows:

typescript
import { createReducer, on } from ‘@ngrx/store’;
import { CounterActionTypes } from ‘./counter.actions’;
import { CounterState } from ‘./counter.state’;

export const initialState: CounterState = {
count: 0,
};

export const counterReducer = createReducer(
initialState,
on(CounterActionTypes.Increment, (state) => ({
count: state.count + 1,
})),
on(CounterActionTypes.Decrement, (state) => ({
count: state.count – 1,
}))
);

Step 5: Define the effects

Effects are used for handling asynchronous operations, such as HTTP requests. We define effects in a separate file. For example, we can define effects for a counter application as follows:

typescript
import { Injectable } from ‘@angular/core’;
import { Actions, createEffect, ofType } from ‘@ngrx/effects’;
import { Observable, of } from ‘rxjs’;
import { map, catchError, mergeMap } from ‘rxjs/operators’;
import { CounterActionTypes, increment } from ‘./counter.actions’;

@Injectable()
export class CounterEffects {
increment$ = createEffect(() =>
this.actions$.pipe(
ofType(CounterActionTypes.Increment),
mergeMap(() =>
this.myService.increment().pipe(
map(() => increment()),
catchError(() => of({ type: ‘API Error’ }))
)
)
)
);

constructor(private actions$: Actions, private myService: MyService) {}
}

Step 6: Register the state, actions, reducers, and effects

We register the state, actions, reducers, and effects in the app.module.ts file as follows:

typescript
import { NgModule } from ‘@angular/core’;
import { BrowserModule } from ‘@angular/platform-browser’;
import { AppComponent } from ‘./app.component’;
import { StoreModule } from ‘@ngrx/store’;
import { EffectsModule } from ‘@ngrx/effects’;
import { counterReducer } from ‘./counter.reducer’;
import { CounterEffects } from ‘./counter.effects’;
```
@NgModule({
  declarations: [AppComponent],
  imports:
```
April 1, 2023