From 5866a59ed920fdbdba04550e74ae67b4f4f0f2fb Mon Sep 17 00:00:00 2001
From: Arman Ozak <arman@armanozak.com>
Date: Fri, 29 Jan 2021 14:18:57 +0300
Subject: [PATCH] add a service for getting navigation events stream

---
 .../packages/core/src/lib/services/index.ts   |  1 +
 .../lib/services/navigation-events.service.ts | 36 +++++++++
 .../tests/navigation-events.service.spec.ts   | 75 +++++++++++++++++++
 3 files changed, 112 insertions(+)
 create mode 100644 npm/ng-packs/packages/core/src/lib/services/navigation-events.service.ts
 create mode 100644 npm/ng-packs/packages/core/src/lib/tests/navigation-events.service.spec.ts

diff --git a/npm/ng-packs/packages/core/src/lib/services/index.ts b/npm/ng-packs/packages/core/src/lib/services/index.ts
index 37bc78d606..7044831681 100644
--- a/npm/ng-packs/packages/core/src/lib/services/index.ts
+++ b/npm/ng-packs/packages/core/src/lib/services/index.ts
@@ -9,6 +9,7 @@ export * from './lazy-load.service';
 export * from './list.service';
 export * from './localization.service';
 export * from './multi-tenancy.service';
+export * from './navigation-events.service';
 export * from './permission.service';
 export * from './profile-state.service';
 export * from './profile.service';
diff --git a/npm/ng-packs/packages/core/src/lib/services/navigation-events.service.ts b/npm/ng-packs/packages/core/src/lib/services/navigation-events.service.ts
new file mode 100644
index 0000000000..ff18b65ed3
--- /dev/null
+++ b/npm/ng-packs/packages/core/src/lib/services/navigation-events.service.ts
@@ -0,0 +1,36 @@
+import { Injectable, Type } from '@angular/core';
+import {
+  NavigationCancel,
+  NavigationEnd,
+  NavigationError,
+  NavigationStart,
+  Router,
+  RouterEvent,
+} from '@angular/router';
+import { filter } from 'rxjs/operators';
+
+export type NavigationEventType = 'Cancel' | 'End' | 'Error' | 'Start';
+
+@Injectable({ providedIn: 'root' })
+export class NavigationEvents {
+  private eventTypes = new Map<NavigationEventType, Type<RouterEvent>>([
+    ['Cancel', NavigationCancel],
+    ['End', NavigationEnd],
+    ['Error', NavigationError],
+    ['Start', NavigationStart],
+  ]);
+
+  constructor(private router: Router) {}
+
+  getOneOf(...eventTypes: NavigationEventType[]) {
+    return this.router.events.pipe(
+      filter((event: RouterEvent) =>
+        eventTypes.some(type => event instanceof this.eventTypes.get(type)),
+      ),
+    );
+  }
+
+  getAny() {
+    return this.getOneOf(...this.eventTypes.keys());
+  }
+}
diff --git a/npm/ng-packs/packages/core/src/lib/tests/navigation-events.service.spec.ts b/npm/ng-packs/packages/core/src/lib/tests/navigation-events.service.spec.ts
new file mode 100644
index 0000000000..cf6d2992d0
--- /dev/null
+++ b/npm/ng-packs/packages/core/src/lib/tests/navigation-events.service.spec.ts
@@ -0,0 +1,75 @@
+import {
+  NavigationCancel,
+  NavigationEnd,
+  NavigationError,
+  NavigationStart,
+  Router,
+  RouterEvent,
+} from '@angular/router';
+import { createServiceFactory, SpectatorService } from '@ngneat/spectator/jest';
+import { Subject } from 'rxjs';
+import { take } from 'rxjs/operators';
+import { NavigationEvents } from '../services/navigation-events.service';
+
+describe('NavigationEvents', () => {
+  let spectator: SpectatorService<NavigationEvents>;
+  let service: NavigationEvents;
+  const events = new Subject<RouterEvent>();
+
+  const createService = createServiceFactory({
+    service: NavigationEvents,
+    providers: [
+      {
+        provide: Router,
+        useValue: { events },
+      },
+    ],
+  });
+
+  beforeEach(() => {
+    spectator = createService();
+    service = spectator.service;
+  });
+
+  describe('getOneOf', () => {
+    test.each`
+      filtered               | expected
+      ${['Start', 'Cancel']} | ${[0, 3]}
+      ${['Error', 'Cancel']} | ${[0, 1]}
+      ${['Start', 'End']}    | ${[2, 3]}
+      ${['Error', 'End']}    | ${[1, 2]}
+    `('should return a stream of given navigation events', ({ filtered, expected }) => {
+      const stream = service.getOneOf(...filtered);
+      const collected: number[] = [];
+
+      stream.pipe(take(2)).subscribe(event => collected.push(event.id));
+
+      events.next(new NavigationCancel(0, null, null));
+      events.next(new NavigationError(1, null, null));
+      events.next(new NavigationEnd(2, null, null));
+      events.next(new NavigationStart(3, null, null));
+
+      expect(collected).toEqual(expected);
+    });
+  });
+
+  describe('getAny', () => {
+    it('should return a stream of any navigation event', () => {
+      const stream = service.getAny();
+      const collected: number[] = [];
+
+      stream.pipe(take(4)).subscribe(event => collected.push(event.id));
+
+      events.next(new RouterEvent(0, null));
+      events.next(new NavigationStart(1, null, null));
+      events.next(new RouterEvent(2, null));
+      events.next(new RouterEvent(3, null));
+      events.next(new NavigationError(4, null, null));
+      events.next(new NavigationEnd(5, null, null));
+      events.next(new RouterEvent(6, null));
+      events.next(new NavigationCancel(7, null, null));
+
+      expect(collected).toEqual([1, 4, 5, 7]);
+    });
+  });
+});