[Port main] Exclude search and browse from Angular SSR (#3709)

config/config.example.yml

@@ -25,6 +25,14 @@ ssr:
   inlineCriticalCss: false
   # Path prefixes to enable SSR for. By default these are limited to paths of primary DSpace objects.
   paths: [ '/home', '/items/', '/entities/', '/collections/', '/communities/', '/bitstream/', '/bitstreams/', '/handle/' ]
+  # Whether to enable rendering of Search component on SSR.
+  # If set to true the component will be included in the HTML returned from the server side rendering.
+  # If set to false the component will not be included in the HTML returned from the server side rendering.
+  enableSearchComponent: false,
+  # Whether to enable rendering of Browse component on SSR.
+  # If set to true the component will be included in the HTML returned from the server side rendering.
+  # If set to false the component will not be included in the HTML returned from the server side rendering.
+  enableBrowseComponent: false,
 
 # The REST API server settings
 # NOTE: these settings define which (publicly available) REST API to use. They are usually
@@ -450,6 +458,12 @@ search:
     enabled: false
     # List of filters to enable in "Advanced Search" dropdown
     filter: [ 'title', 'author', 'subject', 'entityType' ]
+  #
+  # Number used to render n UI elements called loading skeletons that act as placeholders.
+  # These elements indicate that some content will be loaded in their stead.
+  # Since we don't know how many filters will be loaded before we receive a response from the server we use this parameter for the skeletons count.
+  # e.g. If we set 5 then 5 loading skeletons will be visualized before the actual filters are retrieved.
+  defaultFiltersCount: 5
 
 
 # Notify metrics

package.json

@@ -154,6 +154,7 @@
     "ng2-nouislider": "^2.0.0",
     "ngx-infinite-scroll": "^16.0.0",
     "ngx-pagination": "6.0.3",
+    "ngx-skeleton-loader": "^9.0.0",
     "ngx-ui-switch": "^14.1.0",
     "nouislider": "^15.7.1",
     "orejime": "^2.3.1",

src/app/browse-by/browse-by-date/browse-by-date.component.spec.ts

@@ -2,10 +2,13 @@ import { CommonModule } from '@angular/common';
 import {
   ChangeDetectorRef,
   NO_ERRORS_SCHEMA,
+  PLATFORM_ID,
 } from '@angular/core';
 import {
   ComponentFixture,
+  fakeAsync,
   TestBed,
+  tick,
   waitForAsync,
 } from '@angular/core/testing';
 import {
@@ -26,6 +29,7 @@ import { BrowseEntrySearchOptions } from '../../core/browse/browse-entry-search-
 import { SortDirection } from '../../core/cache/models/sort-options.model';
 import { DSpaceObjectDataService } from '../../core/data/dspace-object-data.service';
 import { PaginationService } from '../../core/pagination/pagination.service';
+import { BrowseEntry } from '../../core/shared/browse-entry.model';
 import { Community } from '../../core/shared/community.model';
 import { Item } from '../../core/shared/item.model';
 import { ThemedBrowseByComponent } from '../../shared/browse-by/themed-browse-by.component';
@@ -123,6 +127,7 @@ describe('BrowseByDateComponent', () => {
         { provide: ChangeDetectorRef, useValue: mockCdRef },
         { provide: Store, useValue: {} },
         { provide: APP_CONFIG, useValue: environment },
+        { provide: PLATFORM_ID, useValue: 'browser' },
       ],
       schemas: [NO_ERRORS_SCHEMA],
     })
@@ -172,4 +177,33 @@ describe('BrowseByDateComponent', () => {
     //expect(comp.startsWithOptions[0]).toEqual(new Date().getUTCFullYear());
     expect(comp.startsWithOptions[0]).toEqual(1960);
   });
+
+  describe('when rendered in SSR', () => {
+    beforeEach(() => {
+      comp.platformId = 'server';
+      spyOn((comp as any).browseService, 'getBrowseItemsFor');
+    });
+
+    it('should not call getBrowseItemsFor on init', (done) => {
+      comp.ngOnInit();
+      expect((comp as any).browseService.getBrowseItemsFor).not.toHaveBeenCalled();
+      comp.loading$.subscribe((res) => {
+        expect(res).toBeFalsy();
+        done();
+      });
+    });
+  });
+
+  describe('when rendered in CSR', () => {
+    beforeEach(() => {
+      comp.platformId = 'browser';
+      spyOn((comp as any).browseService, 'getBrowseItemsFor').and.returnValue(createSuccessfulRemoteDataObject$(new BrowseEntry()));
+    });
+
+    it('should call getBrowseItemsFor on init', fakeAsync(() => {
+      comp.ngOnInit();
+      tick(100);
+      expect((comp as any).browseService.getBrowseItemsFor).toHaveBeenCalled();
+    }));
+  });
 });

src/app/browse-by/browse-by-date/browse-by-date.component.ts

@@ -1,12 +1,14 @@
 import {
   AsyncPipe,
+  isPlatformServer,
   NgIf,
 } from '@angular/common';
 import {
   ChangeDetectorRef,
   Component,
   Inject,
   OnInit,
+  PLATFORM_ID,
 } from '@angular/core';
 import {
   ActivatedRoute,
@@ -17,6 +19,7 @@ import { TranslateModule } from '@ngx-translate/core';
 import {
   combineLatest as observableCombineLatest,
   Observable,
+  of as observableOf,
 } from 'rxjs';
 import {
   map,
@@ -28,6 +31,7 @@ import {
   APP_CONFIG,
   AppConfig,
 } from '../../../config/app-config.interface';
+import { environment } from '../../../environments/environment';
 import { DSONameService } from '../../core/breadcrumbs/dso-name.service';
 import { BrowseService } from '../../core/browse/browse.service';
 import {
@@ -99,11 +103,16 @@ export class BrowseByDateComponent extends BrowseByMetadataComponent implements
     @Inject(APP_CONFIG) public appConfig: AppConfig,
     public dsoNameService: DSONameService,
     protected cdRef: ChangeDetectorRef,
+    @Inject(PLATFORM_ID) public platformId: any,
   ) {
-    super(route, browseService, dsoService, paginationService, router, appConfig, dsoNameService);
+    super(route, browseService, dsoService, paginationService, router, appConfig, dsoNameService, platformId);
   }
 
   ngOnInit(): void {
+    if (!this.renderOnServerSide && !environment.ssr.enableBrowseComponent && isPlatformServer(this.platformId)) {
+      this.loading$ = observableOf(false);
+      return;
+    }
     const sortConfig = new SortOptions('default', SortDirection.ASC);
     this.startsWithType = StartsWithType.date;
     this.currentPagination$ = this.paginationService.getCurrentPagination(this.paginationConfig.id, this.paginationConfig);

src/app/browse-by/browse-by-metadata/browse-by-metadata.component.html

@@ -1,4 +1,4 @@
-<section class="comcol-page-browse-section">
+<section class="comcol-page-browse-section" *ngIf="(!ssrRenderingDisabled)">
   <div class="browse-by-metadata w-100">
     <ds-browse-by *ngIf="(loading$ | async) !== true" class="col-xs-12 w-100"
                          title="{{'browse.title' | translate:{

src/app/browse-by/browse-by-metadata/browse-by-metadata.component.spec.ts

@@ -1,8 +1,13 @@
 import { CommonModule } from '@angular/common';
-import { NO_ERRORS_SCHEMA } from '@angular/core';
+import {
+  NO_ERRORS_SCHEMA,
+  PLATFORM_ID,
+} from '@angular/core';
 import {
   ComponentFixture,
+  fakeAsync,
   TestBed,
+  tick,
   waitForAsync,
 } from '@angular/core/testing';
 import { NoopAnimationsModule } from '@angular/platform-browser/animations';
@@ -147,6 +152,7 @@ describe('BrowseByMetadataComponent', () => {
         { provide: ThemeService, useValue: getMockThemeService() },
         { provide: SelectableListService, useValue: {} },
         { provide: HostWindowService, useValue: {} },
+        { provide: PLATFORM_ID, useValue: 'browser' },
       ],
       schemas: [NO_ERRORS_SCHEMA],
     })
@@ -259,6 +265,35 @@ describe('BrowseByMetadataComponent', () => {
       expect(result.fetchThumbnail).toBeTrue();
     });
   });
+
+  describe('when rendered in SSR', () => {
+    beforeEach(() => {
+      comp.ssrRenderingDisabled = true;
+      spyOn((comp as any).browseService, 'getBrowseEntriesFor').and.returnValue(createSuccessfulRemoteDataObject$(null));
+    });
+
+    it('should not call getBrowseEntriesFor on init', (done) => {
+      comp.ngOnInit();
+      expect((comp as any).browseService.getBrowseEntriesFor).not.toHaveBeenCalled();
+      comp.loading$.subscribe((res) => {
+        expect(res).toBeFalsy();
+        done();
+      });
+    });
+  });
+
+  describe('when rendered in CSR', () => {
+    beforeEach(() => {
+      comp.ssrRenderingDisabled = false;
+      spyOn((comp as any).browseService, 'getBrowseEntriesFor').and.returnValue(createSuccessfulRemoteDataObject$(new BrowseEntry()));
+    });
+
+    it('should call getBrowseEntriesFor on init', fakeAsync(() => {
+      comp.ngOnInit();
+      tick(100);
+      expect((comp as any).browseService.getBrowseEntriesFor).toHaveBeenCalled();
+    }));
+  });
 });
 
 export function toRemoteData(objects: any[]): Observable<RemoteData<PaginatedList<any>>> {

src/app/browse-by/browse-by-metadata/browse-by-metadata.component.ts

@@ -1,5 +1,6 @@
 import {
   AsyncPipe,
+  isPlatformServer,
   NgIf,
 } from '@angular/common';
 import {
@@ -9,6 +10,7 @@ import {
   OnChanges,
   OnDestroy,
   OnInit,
+  PLATFORM_ID,
 } from '@angular/core';
 import {
   ActivatedRoute,
@@ -33,6 +35,7 @@ import {
   APP_CONFIG,
   AppConfig,
 } from '../../../config/app-config.interface';
+import { environment } from '../../../environments/environment';
 import { DSONameService } from '../../core/breadcrumbs/dso-name.service';
 import { BrowseService } from '../../core/browse/browse.service';
 import { BrowseEntrySearchOptions } from '../../core/browse/browse-entry-search-options.model';
@@ -114,6 +117,11 @@ export class BrowseByMetadataComponent implements OnInit, OnChanges, OnDestroy {
    */
   @Input() displayTitle = true;
 
+  /**
+   * Defines whether to fetch search results during SSR execution
+   */
+  @Input() renderOnServerSide: boolean;
+
   scope$: BehaviorSubject<string> = new BehaviorSubject(undefined);
 
   /**
@@ -194,6 +202,10 @@ export class BrowseByMetadataComponent implements OnInit, OnChanges, OnDestroy {
    * Observable determining if the loading animation needs to be shown
    */
   loading$ = observableOf(true);
+  /**
+   * Whether this component should be rendered or not in SSR
+   */
+  ssrRenderingDisabled = false;
 
   public constructor(protected route: ActivatedRoute,
                      protected browseService: BrowseService,
@@ -202,18 +214,23 @@ export class BrowseByMetadataComponent implements OnInit, OnChanges, OnDestroy {
                      protected router: Router,
                      @Inject(APP_CONFIG) public appConfig: AppConfig,
                      public dsoNameService: DSONameService,
+                     @Inject(PLATFORM_ID) public platformId: any,
   ) {
     this.fetchThumbnails = this.appConfig.browseBy.showThumbnails;
     this.paginationConfig = Object.assign(new PaginationComponentOptions(), {
       id: BBM_PAGINATION_ID,
       currentPage: 1,
       pageSize: this.appConfig.browseBy.pageSize,
     });
+    this.ssrRenderingDisabled = !this.renderOnServerSide && !environment.ssr.enableBrowseComponent && isPlatformServer(this.platformId);
   }
 
 
   ngOnInit(): void {
-
+    if (this.ssrRenderingDisabled) {
+      this.loading$ = observableOf(false);
+      return;
+    }
     const sortConfig = new SortOptions('default', SortDirection.ASC);
     this.updatePage(getBrowseSearchOptions(this.defaultBrowseId, this.paginationConfig, sortConfig));
     this.currentPagination$ = this.paginationService.getCurrentPagination(this.paginationConfig.id, this.paginationConfig);
@@ -336,7 +353,6 @@ export class BrowseByMetadataComponent implements OnInit, OnChanges, OnDestroy {
     this.paginationService.clearPagination(this.paginationConfig.id);
   }
 
-
 }
 
 /**

src/app/browse-by/browse-by-title/browse-by-title.component.spec.ts

@@ -5,7 +5,9 @@ import {
 import { NO_ERRORS_SCHEMA } from '@angular/core';
 import {
   ComponentFixture,
+  fakeAsync,
   TestBed,
+  tick,
   waitForAsync,
 } from '@angular/core/testing';
 import {
@@ -23,6 +25,7 @@ import { BrowseService } from '../../core/browse/browse.service';
 import { DSpaceObjectDataService } from '../../core/data/dspace-object-data.service';
 import { ItemDataService } from '../../core/data/item-data.service';
 import { PaginationService } from '../../core/pagination/pagination.service';
+import { BrowseEntry } from '../../core/shared/browse-entry.model';
 import { Community } from '../../core/shared/community.model';
 import { Item } from '../../core/shared/item.model';
 import { ThemedBrowseByComponent } from '../../shared/browse-by/themed-browse-by.component';
@@ -81,6 +84,7 @@ describe('BrowseByTitleComponent', () => {
 
   const activatedRouteStub = Object.assign(new ActivatedRouteStub(), {
     params: observableOf({}),
+    queryParams: observableOf({}),
     data: observableOf({ metadata: 'title' }),
   });
 
@@ -127,4 +131,35 @@ describe('BrowseByTitleComponent', () => {
       expect(result.payload.page).toEqual(mockItems);
     });
   });
+
+  describe('when rendered in SSR', () => {
+    beforeEach(() => {
+      comp.platformId = 'server';
+      spyOn((comp as any).browseService, 'getBrowseItemsFor');
+      fixture.detectChanges();
+    });
+
+    it('should not call getBrowseItemsFor on init', (done) => {
+      comp.ngOnInit();
+      expect((comp as any).browseService.getBrowseItemsFor).not.toHaveBeenCalled();
+      comp.loading$.subscribe((res) => {
+        expect(res).toBeFalsy();
+        done();
+      });
+    });
+  });
+
+  describe('when rendered in CSR', () => {
+    beforeEach(() => {
+      comp.platformId = 'browser';
+      fixture.detectChanges();
+      spyOn((comp as any).browseService, 'getBrowseItemsFor').and.returnValue(createSuccessfulRemoteDataObject$(new BrowseEntry()));
+    });
+
+    it('should call getBrowseItemsFor on init', fakeAsync(() => {
+      comp.ngOnInit();
+      tick(100);
+      expect((comp as any).browseService.getBrowseItemsFor).toHaveBeenCalled();
+    }));
+  });
 });