AngularLocalCacheCopy

export class PostService {

  url = 'https://jsonplaceholder.typicode.com/posts';
  initialPosts: Post[] = [
    {id: 0, title: 'test 1', userId: 1, body: 'body 1'},
    {id: 1, title: 'test 2', userId: 1, body: 'body 2'},
    {id: 2, title: 'test 3', userId: 1, body: 'body 3'},
    {id: 3, title: 'test 4', userId: 1, body: 'body 4'},
    {id: 4, title: 'test 5', userId: 1, body: 'body 5'},
  ];

  constructor(private http: HttpClient) {
  }

  public getPosts(): Observable<Post[]> {
    // .startWith() to emit local cache copy for initial data before HTTP response ready
    return this.http.get<Post[]>(this.url).pipe(delay(3000), startWith(this.initialPosts));
  }
}

This project was generated with Angular CLI version 10.1.3.

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