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diff --git a/src/app/services/auth.service.ts b/src/app/services/auth.service.ts
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+/*
+ * Copyright (c) 2022. Deutsche Telekom AG
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+
+import { Injectable } from '@angular/core';
+import { OAuthService, UserInfo } from 'angular-oauth2-oidc';
+import { catchError, filter, map } from 'rxjs/operators';
+import { NavigationStart, Router } from '@angular/router';
+import { AlertService } from '../modules/alerting';
+import { TranslateService } from '@ngx-translate/core';
+import { BehaviorSubject, EMPTY, Observable, of } from 'rxjs';
+
+/**
+ * Provides check for roles and token
+ */
+@Injectable({
+  providedIn: 'root',
+})
+export class AuthService {
+  userProfile$ = new BehaviorSubject<UserInfo | undefined>(undefined);
+  constructor(private readonly oauthService: OAuthService, private router: Router, private alertService: AlertService, private translateService: TranslateService) {
+    //renew cache every page reload
+    router.events.pipe(
+      filter((e): e is NavigationStart => e instanceof NavigationStart)
+    ).subscribe(() => {
+      try {
+        return this.loadUserProfile().then(userInfo => this.userProfile$.next(userInfo)).catch(e => {throw e})
+      }catch (e) {
+        this.alertService.error(this.translateService.instant('common.messages.keycloakAccessTokenNotValid'), {id: "keycloak", keepAfterRouteChange: true})
+        return Promise.resolve(null);
+      }
+    });
+  }
+
+  userProfileCache: UserInfo | undefined = undefined;
+
+  /**
+   * Convenience method of `hasValidAccessToken()` and `hasSufficientRoles()`
+   * Asynchronous because the needed UserInfo is fetched from Keycloak
+   */
+  hasPermissions(): Observable<boolean> {
+    if (this.hasValidAccessToken()) {
+      return this.hasSufficientRoles();
+    }
+    return of(false);
+  }
+
+  /**
+   * This answers: 'What if the user has an account, but without any permissions?'
+   * Asynchronous because the needed UserInfo is fetched from Keycloak
+   */
+  hasSufficientRoles(): Observable<boolean> {
+    return this.loadCachedUserProfile().pipe(map(info => info?.roles.join(',') !== 'offline_access'));
+  }
+
+  loadCachedUserProfile(): Observable<UserInfo | undefined> {
+    return this.userProfile$.pipe(
+      filter(userProfile => userProfile !== undefined),
+      catchError(err => {
+        console.error(err);
+        return EMPTY
+      }));
+  }
+
+  /**
+   * Wrapper for `hasValidAccessToken` from OAuthService
+   */
+  hasValidAccessToken(): boolean {
+    return this.oauthService.hasValidAccessToken();
+  }
+  /*
+  * Private method = should not be used outside of this class, because it triggers additional request for userprofile
+  * */
+  private loadUserProfile():Promise<UserInfo> {
+    // in version 12.2 loadUserProfile() Promise returns data of type object instead of UserInfo
+    //@ts-ignore
+    return this.oauthService.loadUserProfile().then(userInfo => userInfo.info as UserInfo)
+  }
+}