Add file upload functionality with dialog components and update image handling

jambotron-ui/src/app/modules/user-module/user-api.service.ts

@@ -1,7 +1,7 @@
 import { Injectable } from '@angular/core';
 import {forkJoin, Observable} from 'rxjs';
 import {Tutorial} from '../../models/tutorial.model';
-import {HttpClient, HttpHeaders} from '@angular/common/http';
+import {HttpClient, HttpEvent, HttpHeaders, HttpRequest} from '@angular/common/http';
 import {GlobalConstants} from '../../global-constants';
 import {FileInfo} from '../../models/file-info';
 
@@ -15,6 +15,19 @@ export class UserApiService {
 
   }
 
+  upload(file: File): Observable<HttpEvent<any>> {
+    const formData: FormData = new FormData();
+    formData.append('file', file);
+
+    const req = new HttpRequest('POST', `${this.baseUrl}/upload`, formData, {
+      reportProgress: true,
+      responseType: 'json'
+    });
+
+    return this.http.request(req);
+  }
+
+
   saveZhipuaiImage(url: string): Observable<any> {
     return this.http.post(`${this.baseUrl}/saveZhipuAiImage`, {imageUrl:url});
   }