120. Creating Interceptor (#14 Section 16: Interceptor)

support-portal-frontend/src/app/interceptor/auth.interceptor.ts

@@ -0,0 +1,49 @@
+import {Injectable} from '@angular/core';
+import {HttpEvent, HttpHandler, HttpInterceptor, HttpRequest} from '@angular/common/http';
+import {Observable} from 'rxjs';
+import {environment} from "../../environments/environment";
+import {AuthenticationService} from "../service/authentication.service";
+
+@Injectable()
+export class AuthInterceptor implements HttpInterceptor {
+
+  private publicUrlPatterns: string[] = [];
+  private host: string = environment.apiUrl;
+
+  constructor(private authenticationService: AuthenticationService) {
+    let publicUrlsSpringPatterns: string[] = environment.publicUrls;
+    let hostPattern = this.host.replace("/", "\/");
+    for (const urlPattern of publicUrlsSpringPatterns) {
+
+      let newUrlPattern = urlPattern
+        .replace('/**', "\/.*")
+        .replace('/*', '\/[A-Za-z0-9\-\.]+')
+        +"$";
+      this.publicUrlPatterns.push(hostPattern + newUrlPattern);
+    }
+  }
+
+  intercept(request: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
+
+    if (this.isRequestUrlMatches(request.url)) {
+      request = this.injectAuthToken(request);
+    }
+    return next.handle(request);
+  }
+
+  private injectAuthToken(request: HttpRequest<any>) {
+    this.authenticationService.loadToken();
+    const token = this.authenticationService.getToken();
+    request = request.clone({
+      setHeaders: {
+        Authorization: `Bearer ${token}`
+      }
+    });
+    return request;
+  }
+
+  public isRequestUrlMatches(requestUrl: string): boolean {
+    return requestUrl.includes(this.host) &&
+      !this.publicUrlPatterns.some(urlPattern => requestUrl.match(urlPattern));
+  }
+}