interceptors for caching

ignatandrei · Jan 19, 2020 · 2bde813 · 2bde813
1 parent 66e3588
commit 2bde813
Show file tree

Hide file tree

Showing 3 changed files with 23 additions and 12 deletions.
diff --git a/InfoValutar/InfovalutarWebAng/src/app/app.module.ts b/InfoValutar/InfovalutarWebAng/src/app/app.module.ts
@@ -16,7 +16,8 @@ import { FormsModule } from '@angular/forms';
 import { BankComponent } from './bank/bank.component';
 import { DashboardComponent } from './dashboard/dashboard.component';
 import { ProgrammerComponent } from './programmer/programmer.component';
-
+import { CachingInterceptor } from 'src/utils/CachingInterceptor';
+import {HTTP_INTERCEPTORS} from '@angular/common/http';
 @NgModule({
   declarations: [
     AppComponent,
@@ -38,7 +39,11 @@ import { ProgrammerComponent } from './programmer/programmer.component';
     MatIconModule,
     MatListModule
   ],
-  providers: [],
+  providers: [ {
+    provide: HTTP_INTERCEPTORS,
+    useClass: CachingInterceptor,
+    multi: true
+}, ],
   bootstrap: [AppComponent]
 })
 export class AppModule { }
diff --git a/InfoValutar/InfovalutarWebAng/src/environments/environment.ts b/InfoValutar/InfovalutarWebAng/src/environments/environment.ts
@@ -4,7 +4,7 @@
 
 export const environment = {
   production: false,
-  url: 'http://localhost:44385/'
+  url: 'https://localhost:44385/'
 };
 
 /*

diff --git a/InfoValutar/InfovalutarWebAng/src/utils/CachingInterceptor.ts b/InfoValutar/InfovalutarWebAng/src/utils/CachingInterceptor.ts
@@ -7,21 +7,25 @@ import { tap, startWith } from 'rxjs/operators';
 
 @Injectable()
 export class CachingInterceptor implements HttpInterceptor {
-  cache: Map<string, any> = new Map<string, any>();
+  static cache: Map<string, any> = new Map<string, any>();
   constructor() {}
 
   intercept(req: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
     // continue if not cachable.
-    if (this.isCachable(req)) { return next.handle(req); }
+
+    if (!this.isCachable(req)) { return next.handle(req); }
+    console.log(`start intercept ${req.url} ${this.isCachable(req)}`);
     let obsCache: HttpResponse<any> = null;
-    if (this.cache.has(req.url)) {
+    if (CachingInterceptor.cache.has(req.url)) {
         console.log('exists in cache');
-        const cachedResponse = this.cache.get(req.url);
+        const cachedResponse = CachingInterceptor.cache.get(req.url);
         obsCache =  new HttpResponse({ body: cachedResponse });
     }
 
-    let sendDataAndCache$ = this.sendRequestAndCache(req, next);
+    const duplicate = req.clone();
-    if(obsCache) {
+    console.log(`${req.url} exists in cache  ${CachingInterceptor.cache.has(req.url)}  ${obsCache != null}`);
+    let sendDataAndCache$ = this.sendRequestAndCache(duplicate, next);
+    if (obsCache != null) {
        sendDataAndCache$ = sendDataAndCache$.pipe(
            tap(e => {
                console.log('from cache');
@@ -36,12 +40,14 @@ export class CachingInterceptor implements HttpInterceptor {
     req: HttpRequest<any>,
     next: HttpHandler,
     ): Observable<HttpEvent<any>> {
-
+      const url = req.url;
-    return next.handle(req).pipe(
+      return next.handle(req).pipe(
       tap(event => {
+        console.log(`in the tap for ${url} ${event instanceof HttpResponse}`);
         // There may be other events besides the response.
         if (event instanceof HttpResponse) {
-          this.cache[req.url] = event.body; // Update the cache.
+          CachingInterceptor.cache.set(url,event.body); // Update the cache.
+          //console.log(`added cache for ${url} with value ${event.body}`);
         }
       })
     );