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diff --git a/src/app/http-interceptors/caching-interceptor.ts b/src/app/http-interceptors/caching-interceptor.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 { HttpEvent, HttpHandler, HttpInterceptor, HttpRequest, HttpResponse } from '@angular/common/http';
+import { Injectable } from '@angular/core';
+import { Observable, of } from 'rxjs';
+import { startWith, tap } from 'rxjs/operators';
+
+import { RequestCache } from '../services/cacheservice/request-cache.service';
+import { urlTileApi } from '../services/tileservice/tiles.service';
+
+/**
+ * Interceptor that returns HttpResponses from cache and updates cache if outdated
+ * This applies to GET requests from specified urls (specified in this class)
+ */
+@Injectable()
+// https://angular.io/guide/http#using-interceptors-for-caching
+// https://github.com/angular/angular/blob/master/aio/content/examples/http/src/app/http-interceptors/caching-interceptor.ts
+export class CachingInterceptor implements HttpInterceptor {
+  private cachedUrls: Array<string> = [
+    urlTileApi,
+    window.location.origin + '/keycloak/auth/realms/ONAP/protocol/openid-connect/userinfo',
+  ];
+
+  // cache is the cache service that supports get() and put()
+  constructor(private cache: RequestCache) {}
+
+  intercept(request: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
+    // continue if not cacheable.
+    if (!this.isCacheable(request)) {
+      return next.handle(request);
+    }
+
+    const cachedResponse = this.cache.get(request);
+
+    // when a custom 'x-refresh' header is set, refresh the cash
+    // (see https://github.com/angular/angular/blob/master/aio/content/examples/http/src/app/package-search/package-search.service.ts)
+    if (request.headers.get('x-refresh')) {
+      const results$ = this.getUpdatedResponse(request, next, this.cache);
+      return cachedResponse ? results$.pipe(startWith(cachedResponse)) : results$;
+    }
+    // cache-or-fetch
+    return cachedResponse ? of(cachedResponse) : this.getUpdatedResponse(request, next, this.cache);
+  }
+
+  /**
+   * Checks if the request is cacheable.
+   * This is true if the request is a http GET and the url is defined in this method
+   * (-> urlTileApi)
+   */
+  private isCacheable(req: HttpRequest<any>): boolean {
+    // Only GET requests are cacheable
+    return (
+      req.method === 'GET' &&
+      // Only the tile api is cacheable in this app
+      -1 < this.cachedUrls.indexOf(req.url)
+    );
+  }
+
+  /**
+   * Get server response observable by sending request to `next()`.
+   * Will add the response to the cache on the way out.
+   */
+  private getUpdatedResponse(
+    req: HttpRequest<any>,
+    next: HttpHandler,
+    cache: RequestCache,
+  ): Observable<HttpEvent<any>> {
+    return next.handle(req.clone()).pipe(
+      tap(event => {
+        // There may be other events besides the response.
+        if (event instanceof HttpResponse) {
+          cache.put(req, event); // Update the cache.
+        }
+      }),
+    );
+  }
+}