Adding the service and interface code

Here's the code for the service; open the generated file called api.ts and add it:

import { HttpClient, HttpParams } from '@angular/common/http';
import { Injectable } from '@angular/core';
import { Observable } from 'rxjs';
import { MediaItem, Book, Movie, Music, SearchOptions } from './media';

@Injectable({
  providedIn: 'root'
})
export class Api {
    private readonly apiUrl = 'http://localhost:3000';

    constructor (private http: HttpClient) { }

    loadDemoDataIntoGolem(): Observable<string> {
        return this.http.get<string>(`${this.apiUrl}/load-data`);
    }

    getByKey(key: string): Observable<MediaItem> {
        return this.http.get<MediaItem>(`${this.apiUrl}/key/${key}`);
    }

    getAll(): Observable<MediaItem[]> {
        return this.http.get<MediaItem[]>(`${this.apiUrl}/query`);
    }

    getBooks(): Observable<MediaItem[]> {
        return this.http.get<Book[]>(`${this.apiUrl}/query?type=books`);
    }

    getMusic(): Observable<MediaItem[]> {
        return this.http.get<Music[]>(`${this.apiUrl}/query?type=music`);
    }

    getMovies(): Observable<MediaItem[]> {
        return this.http.get<Movie[]>(`${this.apiUrl}/query?type=movies`);
    }

    getSearchOptions(): Observable<SearchOptions> {
        return this.http.get<SearchOptions>(`${this.apiUrl}/search-options`);
    }

    executeQuery(query: string): Observable<any[]> {
        return this.http.get<any[]>(`${this.apiUrl}/query?${query}`);
    }

    save(item: MediaItem): Observable<any> {
        // This will POST the complete object to a /media endpoint
        return this.http.post<any>(`${this.apiUrl}/save`, item);
    }

    purge(): Observable<any> {
        return this.http.get<any>(`${this.apiUrl}/purge`)
    }
}

And here's the interface. Open the generated file called media.ts and add the following:

export interface BookCreate {
    type: "book";
    title: string;
    description: string;
    author: string;
    genre: string;
    rating: number;
    owned: boolean;
    year: number;
}

export interface Book extends BookCreate {
    key: string;
    auto_generated: string;
}

export interface MovieCreate {
    type: "movie";
    title: string;
    description: string;
    director: string;
    genre: string;
    rating: number;
    watched: boolean;
    year: number;
}

export interface Movie extends MovieCreate {
    key: string;
    auto_generated: string;
}


export interface MusicCreate {
    type: "music";
    title: string;
    description: string;
    artist: string;
    genre: string;
    rating: number;
    favorite: boolean;
    year: number;
}

export interface Music extends MusicCreate {
    key: string;
    auto_generated: string;
}

export type MediaItem = Book | Movie | Music;

export interface SearchOptions {
  directors: string[];
  artists: string[];
  authors: string[];
  movie_genres: string[];
  music_genres: string[];
  book_genres: string[];
}

That's all the code! In the next step we'll walk through running everything, and then after that we'll do a walkthrough of what the code does.

Head to Step 7.