LibroService

Overview

The LibroService provides methods to create, read, update, and delete books in the Biblioteca Virtual system. It handles all HTTP communications with the backend /libros endpoint. Location: src/app/core/services/libro.ts

Constructor

private http = inject(HttpClient);

Uses Angular’s inject() function to obtain HttpClient instance.

Properties

string

default:"${environment.apiUrl}/libros"

Base URL for libro endpoints, configured from environment settings.

Methods

getAll()

Retrieves all books from the library.

getAll(): Observable<Libro[]>

Returns: Observable<Libro[]> - Array of all books

array

Array of book objects

number

Unique book identifier

string

Book title

string

URL to the book cover image

number

Year of publication

boolean

Whether the book is available for borrowing

Genero

Book’s genre (id and nombre)

Autor[]

Array of authors (id, nombre, urlFoto)

Example:

this.libroService.getAll().subscribe({
  next: (libros) => {
    console.log(`Found ${libros.length} books`);
    this.books = libros;
  },
  error: (error) => {
    console.error('Error fetching books:', error);
  }
});

API Endpoint: GET ${apiUrl}

getById()

Retrieves a specific book by its ID.

getById(id: number): Observable<Libro>

number

required

The unique identifier of the book to retrieve

Returns: Observable<Libro> - Single book object Example:

const libroId = 42;

this.libroService.getById(libroId).subscribe({
  next: (libro) => {
    console.log('Book details:', libro.titulo);
    this.selectedBook = libro;
  },
  error: (error) => {
    console.error('Book not found:', error);
  }
});

API Endpoint: GET ${apiUrl}/{id} Use Case: Loading book data for editing forms

create()

Creates a new book in the library.

create(libro: any): Observable<Libro>

object

required

Book data to create. Must include genero and autores.Required Properties:

titulo (string): Book title
disponible (boolean): Availability status
genero (Genero): Genre object with id and nombre
autores (Autor[]): Array of author objects

Optional Properties:

portada (string): Cover image URL
anioPublicacion (number): Publication year

Returns: Observable<Libro> - The created book with server-assigned ID Example:

const newBook = {
  titulo: 'Cien años de soledad',
  portada: 'https://example.com/cover.jpg',
  anioPublicacion: 1967,
  disponible: true,
  genero: {
    id: 1,
    nombre: 'Realismo Mágico'
  },
  autores: [
    {
      id: 5,
      nombre: 'Gabriel García Márquez',
      urlFoto: 'https://example.com/gabo.jpg'
    }
  ]
};

this.libroService.create(newBook).subscribe({
  next: (createdLibro) => {
    console.log('Book created with ID:', createdLibro.id);
    this.router.navigate(['/libros']);
  },
  error: (error) => {
    console.error('Error creating book:', error);
  }
});

API Endpoint: POST ${apiUrl}

update()

Updates an existing book.

update(id: number, libro: any): Observable<Libro>

number

required

The ID of the book to update

object

required

Updated book data. Should include all required fields (titulo, disponible, genero, autores)

Returns: Observable<Libro> - The updated book object Example:

const updatedBook = {
  titulo: 'Cien años de soledad (Edición Especial)',
  portada: 'https://example.com/new-cover.jpg',
  anioPublicacion: 1967,
  disponible: false, // Currently borrowed
  genero: { id: 1, nombre: 'Realismo Mágico' },
  autores: [{ id: 5, nombre: 'Gabriel García Márquez' }]
};

this.libroService.update(42, updatedBook).subscribe({
  next: (libro) => {
    console.log('Book updated successfully');
    this.loadBooks();
  },
  error: (error) => {
    console.error('Error updating book:', error);
  }
});

API Endpoint: PUT ${apiUrl}/{id}

delete()

Deletes a book from the library.

delete(id: number): Observable<any>

number

required

The ID of the book to delete

Returns: Observable<any> - Plain text response from server Response Type: Text (uses responseType: 'text' to handle empty or plain text responses) Example:

const libroId = 42;

if (confirm('¿Está seguro de eliminar este libro?')) {
  this.libroService.delete(libroId).subscribe({
    next: (response) => {
      console.log('Delete response:', response);
      this.loadBooks(); // Refresh the list
    },
    error: (error) => {
      console.error('Error deleting book:', error);
    }
  });
}

API Endpoint: DELETE ${apiUrl}/{id}

Complete CRUD Example

Example component using all LibroService methods:

import { Component, OnInit, inject } from '@angular/core';
import { LibroService } from '../core/services/libro';
import { Libro } from '../core/models/libro';

@Component({
  selector: 'app-libro-list',
  templateUrl: './libro-list.html'
})
export class LibroListComponent implements OnInit {
  libroService = inject(LibroService);
  libros: Libro[] = [];

  ngOnInit() {
    this.loadLibros();
  }

  loadLibros() {
    this.libroService.getAll().subscribe({
      next: (data) => {
        this.libros = data;
      },
      error: (err) => console.error(err)
    });
  }

  editLibro(id: number) {
    this.libroService.getById(id).subscribe({
      next: (libro) => {
        // Load into edit form
        this.openEditForm(libro);
      }
    });
  }

  deleteLibro(id: number) {
    this.libroService.delete(id).subscribe({
      next: () => {
        this.loadLibros();
      }
    });
  }
}

Data Models

Libro Interface

interface Libro {
  id: number;
  titulo: string;
  portada?: string;
  anioPublicacion?: number;
  disponible: boolean;
  genero: Genero;
  autores: Autor[];
}

interface Genero {
  id: number;
  nombre: string;
}

interface Autor {
  id: number;
  nombre: string;
  urlFoto?: string;
}

Error Handling

All methods return Observables that may emit errors:

this.libroService.getAll().subscribe({
  next: (libros) => { /* success */ },
  error: (error) => {
    if (error.status === 404) {
      console.error('Book not found');
    } else if (error.status === 403) {
      console.error('Access forbidden');
    } else {
      console.error('Unexpected error:', error);
    }
  }
});

Services

Guards

Models

Components

Interceptors

Overview

Constructor

Properties

Methods

getAll()

getById()

create()

update()

delete()

Complete CRUD Example

Data Models

Libro Interface

Error Handling

See Also

​Overview

​Constructor

​Properties

​Methods

​getAll()

​getById()

​create()

​update()

​delete()

​Complete CRUD Example

​Data Models

​Libro Interface

​Related Interfaces

​Error Handling

​See Also

Overview

Constructor

Properties

Methods

getAll()

getById()

create()

update()

delete()

Complete CRUD Example

Data Models

Libro Interface

Related Interfaces

Error Handling

See Also