feat(router): add "onSameUrlNavigation" router configuration option (#19463)

PR Close #19463

packages/router/src/router.ts

@@ -241,6 +241,14 @@ export class Router {
 
   routeReuseStrategy: RouteReuseStrategy = new DefaultRouteReuseStrategy();
 
+  /**
+   * Define what the router should do if it receives a navigation request to the current URL.
+   * By default, the router will ignore this navigation. However, this prevents features such
+   * as a "refresh" button. Use this option to configure the behavior when navigating to the
+   * current URL. Default is 'ignore'.
+   */
+  onSameUrlNavigation: 'reload'|'ignore' = 'ignore';
+
   /**
    * Creates the router service.
    */
@@ -552,7 +560,8 @@ export class Router {
     const url = this.urlHandlingStrategy.extract(rawUrl);
     const urlTransition = !this.navigated || url.toString() !== this.currentUrlTree.toString();
 
-    if (this.urlHandlingStrategy.shouldProcessUrl(rawUrl)) {
+    if ((this.onSameUrlNavigation === 'reload' ? true : urlTransition) &&
+        this.urlHandlingStrategy.shouldProcessUrl(rawUrl)) {
       (this.events as Subject<Event>).next(new NavigationStart(id, this.serializeUrl(url)));
       Promise.resolve()
           .then(

packages/router/src/router_module.ts

@@ -129,12 +129,15 @@ export class RouterModule {
    * Creates a module with all the router providers and directives. It also optionally sets up an
    * application listener to perform an initial navigation.
    *
-   * Options:
+   * Options (see {@link ExtraOptions}):
    * * `enableTracing` makes the router log all its internal events to the console.
    * * `useHash` enables the location strategy that uses the URL fragment instead of the history
    * API.
    * * `initialNavigation` disables the initial navigation.
    * * `errorHandler` provides a custom error handler.
+   * * `preloadingStrategy` configures a preloading strategy (see {@link PreloadAllModules}).
+   * * `onSameUrlNavigation` configures how the router handles navigation to the current URL. See
+   * {@link ExtraOptions} for more details.
    */
   static forRoot(routes: Routes, config?: ExtraOptions): ModuleWithProviders {
     return {
@@ -267,6 +270,14 @@ export interface ExtraOptions {
    * Configures a preloading strategy. See {@link PreloadAllModules}.
    */
   preloadingStrategy?: any;
+
+  /**
+   * Define what the router should do if it receives a navigation request to the current URL.
+   * By default, the router will ignore this navigation. However, this prevents features such
+   * as a "refresh" button. Use this option to configure the behavior when navigating to the
+   * current URL. Default is 'ignore'.
+   */
+  onSameUrlNavigation?: 'reload'|'ignore';
 }
 
 export function setupRouter(
@@ -299,6 +310,10 @@ export function setupRouter(
     });
   }
 
+  if (opts.onSameUrlNavigation) {
+    router.onSameUrlNavigation = opts.onSameUrlNavigation;
+  }
+
   return router;
 }
 

packages/router/test/integration.spec.ts

@@ -53,6 +53,7 @@ describe('Integration', () => {
 
   describe('navigation', function() {
     it('should navigate to the current URL', fakeAsync(inject([Router], (router: Router) => {
+         router.onSameUrlNavigation = 'reload';
          router.resetConfig([
            {path: '', component: SimpleCmp},
            {path: 'simple', component: SimpleCmp},
@@ -3568,30 +3569,34 @@ describe('Integration', () => {
            }]);
 
            const events: any[] = [];
-           router.events.subscribe(e => onlyNavigationStartAndEnd(e) && events.push(e));
+           router.events.subscribe(e => e instanceof RouterEvent && events.push(e));
 
            location.go('/include/user/kate(aux:excluded)');
            advance(fixture);
 
            expect(location.path()).toEqual('/include/user/kate(aux:excluded)');
-           expectEvents(
+           expectEvents(events, [
-               events,
+             [NavigationStart, '/include/user/kate'], [RoutesRecognized, '/include/user/kate'],
-               [[NavigationStart, '/include/user/kate'], [NavigationEnd, '/include/user/kate']]);
+             [GuardsCheckStart, '/include/user/kate'], [GuardsCheckEnd, '/include/user/kate'],
+             [ResolveStart, '/include/user/kate'], [ResolveEnd, '/include/user/kate'],
+             [NavigationEnd, '/include/user/kate']
+           ]);
            events.splice(0);
 
            location.go('/include/user/kate(aux:excluded2)');
            advance(fixture);
-           expectEvents(
+           expectEvents(events, []);
-               events,
-               [[NavigationStart, '/include/user/kate'], [NavigationEnd, '/include/user/kate']]);
-           events.splice(0);
 
            router.navigateByUrl('/include/simple');
            advance(fixture);
 
            expect(location.path()).toEqual('/include/simple(aux:excluded2)');
-           expectEvents(
+           expectEvents(events, [
-               events, [[NavigationStart, '/include/simple'], [NavigationEnd, '/include/simple']]);
+             [NavigationStart, '/include/simple'], [RoutesRecognized, '/include/simple'],
+             [GuardsCheckStart, '/include/simple'], [GuardsCheckEnd, '/include/simple'],
+             [ResolveStart, '/include/simple'], [ResolveEnd, '/include/simple'],
+             [NavigationEnd, '/include/simple']
+           ]);
          })));
     });
   });

tools/public_api_guard/router/router.d.ts

@@ -126,6 +126,7 @@ export interface ExtraOptions {
     enableTracing?: boolean;
     errorHandler?: ErrorHandler;
     initialNavigation?: InitialNavigation;
+    onSameUrlNavigation?: 'reload' | 'ignore';
     preloadingStrategy?: any;
     useHash?: boolean;
 }
@@ -327,6 +328,7 @@ export declare class Router {
     errorHandler: ErrorHandler;
     readonly events: Observable<Event>;
     navigated: boolean;
+    onSameUrlNavigation: 'reload' | 'ignore';
     routeReuseStrategy: RouteReuseStrategy;
     readonly routerState: RouterState;
     readonly url: string;