93219: Move APP_INITIALIZER logic into InitService

src/app/init.service.ts

@@ -0,0 +1,63 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+import { Store } from '@ngrx/store';
+import { AppState } from './app.reducer';
+import { CheckAuthenticationTokenAction } from './core/auth/auth.actions';
+import { CorrelationIdService } from './correlation-id/correlation-id.service';
+import { DSpaceTransferState } from '../modules/transfer-state/dspace-transfer-state.service';
+
+/**
+ * Performs the initialization of the app.
+ *
+ * Should have distinct extensions for server & browser for the specifics.
+ * Should be provided in AppModule as follows
+ * ```
+ * {
+ *   provide: APP_INITIALIZER
+ *   useFactory: (initService: InitService) => initService.init(),
+ *   deps: [ InitService ],
+ *   multi: true,
+ * }
+ * ```
+ *
+ * In order to be injected in the common APP_INITIALIZER,
+ * concrete subclasses should be provided in their respective app modules as
+ * ```
+ * { provide: InitService, useClass: SpecificInitService }
+ * ```
+ */
+export abstract class InitService {
+  protected constructor(
+    protected store: Store<AppState>,
+    protected correlationIdService: CorrelationIdService,
+    protected dspaceTransferState: DSpaceTransferState,
+  ) {
+  }
+
+  /**
+   * Main initialization method, to be used as the APP_INITIALIZER factory.
+   *
+   * Note that the body of this method and the callback it returns are called
+   * at different times.
+   * This is important to take into account when other providers depend on the
+   * initialization logic (e.g. APP_BASE_HREF)
+   */
+  abstract init(): () => Promise<boolean>;
+
+  protected checkAuthenticationToken(): void {
+    this.store.dispatch(new CheckAuthenticationTokenAction());
+  }
+
+  protected initCorrelationId(): void {
+    this.correlationIdService.initCorrelationId();
+  }
+
+  protected async transferAppState(): Promise<unknown> {
+    return this.dspaceTransferState.transfer();
+  }
+}