feat(aio): enable deployment mode to be set via URL query

The deployment mode set from the environment provided at build time;
or overridden by the `mode` query parameter: e.g. `...?mode=archive`

See #18287

aio/src/app/app.component.spec.ts

@@ -906,6 +906,7 @@ describe('AppComponent', () => {
 //// test helpers ////
 
 function createTestingModule(initialUrl: string, mode: string = 'stable') {
+  const mockLocationService = new MockLocationService(initialUrl);
   TestBed.resetTestingModule();
   TestBed.configureTestingModule({
     imports: [ AppModule ],
@@ -913,11 +914,11 @@ function createTestingModule(initialUrl: string, mode: string = 'stable') {
       { provide: APP_BASE_HREF, useValue: '/' },
       { provide: GaService, useClass: TestGaService },
       { provide: Http, useClass: TestHttp },
-      { provide: LocationService, useFactory: () => new MockLocationService(initialUrl) },
+      { provide: LocationService, useFactory: () => mockLocationService },
       { provide: Logger, useClass: MockLogger },
       { provide: SearchService, useClass: MockSearchService },
       { provide: Deployment, useFactory: () => {
-        const deployment = new Deployment();
+        const deployment = new Deployment(mockLocationService as any);
         deployment.mode = mode;
         return deployment;
       }},

aio/src/app/shared/deployment.service.spec.ts

@@ -0,0 +1,32 @@
+import { ReflectiveInjector } from '@angular/core';
+import { environment } from 'environments/environment';
+import { LocationService } from 'app/shared/location.service';
+import { MockLocationService } from 'testing/location.service';
+import { Deployment } from './deployment.service';
+
+describe('Deployment service', () => {
+  describe('mode', () => {
+    it('should get the mode from the environment', () => {
+      environment.mode = 'foo';
+      const deployment = getInjector().get(Deployment);
+      expect(deployment.mode).toEqual('foo');
+    });
+
+    it('should get the mode from the `mode` query parameter if available', () => {
+      const injector = getInjector();
+
+      const locationService: MockLocationService = injector.get(LocationService);
+      locationService.search.and.returnValue({ mode: 'bar' });
+
+      const deployment = injector.get(Deployment);
+      expect(deployment.mode).toEqual('bar');
+    });
+  });
+});
+
+function getInjector() {
+  return ReflectiveInjector.resolveAndCreate([
+    Deployment,
+    { provide: LocationService, useFactory: () => new MockLocationService('') }
+  ]);
+}

aio/src/app/shared/deployment.service.ts

@@ -1,7 +1,17 @@
 import { Injectable } from '@angular/core';
+import { LocationService } from 'app/shared/location.service';
 import { environment } from 'environments/environment';
 
+/**
+ * Information about the deployment of this application.
+ */
 @Injectable()
 export class Deployment {
-  mode: string = environment.mode;
+  /**
+   * The deployment mode set from the environment provided at build time;
+   * or overridden by the `mode` query parameter: e.g. `...?mode=archive`
+   */
+  mode: string = this.location.search()['mode'] || environment.mode;
+
+  constructor(private location: LocationService) {}
 };