add less 6 herro update

src/app/hero-detail/hero-detail.component.html

@@ -1,12 +1,11 @@
 <div *ngIf="hero">
-
-  <button type="button" (click)="goBack()">go back</button>
-
   <h2>{{hero.name | uppercase}} Details</h2>
   <div><span>id: </span>{{hero.id}}</div>
   <div>
     <label for="hero-name">Hero name: </label>
     <input id="hero-name" [(ngModel)]="hero.name" placeholder="name">
   </div>
-
 </div>
+
+<button type="button" (click)="goBack()">go back</button>
+<button type="button" (click)="save()">save</button>

src/app/hero-detail/hero-detail.component.ts

@@ -39,4 +39,11 @@ export class HeroDetailComponent {
       .subscribe(hero => this.hero = hero);
   }
 
+  save(): void {
+    if (this.hero) {
+      this.heroService.updateHero(this.hero)
+        .subscribe(() => this.goBack());
+    }
+  }
+
 }

src/app/hero.service.ts

@@ -3,7 +3,7 @@ import { Hero } from './hero';
 import { HEROES } from './mock-heroes';
 import { Observable, of } from 'rxjs';
 import { MessageService } from './message.service';
-import { HttpClient } from '@angular/common/http';
+import { HttpClient, HttpHeaders } from '@angular/common/http';
 import { catchError, map, tap } from 'rxjs/operators';
 
 @Injectable({
@@ -14,24 +14,39 @@ export class HeroService {
 
   private heroesUrl = 'api/heroes';  // URL to web api
     
+  httpOptions = {
+    headers: new HttpHeaders({ 'Content-Type': 'application/json' })
+  };
+
   constructor(
     private http: HttpClient,
     private messageService: MessageService) 
   { }
 
+  /** GET heroes from the server */
   getHeroes(): Observable<Hero[]> {
     return this.http.get<Hero[]>(this.heroesUrl)
       .pipe(
+        tap(_ => this.log('fetched heroes')),
         catchError(this.handleError<Hero[]>('getHeroes', []))
       );
   }
 
+  /** GET hero by id. Will 404 if id not found */
   getHero(id: number): Observable<Hero> {
-    // For now, assume that a hero with the specified `id` always exists.
+    const url = `${this.heroesUrl}/${id}`;
-    // Error handling will be added in the next step of the tutorial.
+    return this.http.get<Hero>(url).pipe(
-    const hero = HEROES.find(h => h.id === id)!;
+      tap(_ => this.log(`fetched hero id=${id}`)),
-    this.messageService.add(`HeroService: fetched hero id=${id}`);
+      catchError(this.handleError<Hero>(`getHero id=${id}`))
-    return of(hero);
+    );
+  }
+
+  /** PUT: update the hero on the server */
+  updateHero(hero: Hero): Observable<any> {
+    return this.http.put(this.heroesUrl, hero, this.httpOptions).pipe(
+      tap(_ => this.log(`updated hero id=${hero.id}`)),
+      catchError(this.handleError<any>('updateHero'))
+    );
   }
 
     /**