feat(navigation): add token for providing navigation in-memory seed d…

…ata (#2627)

libs/navigation/driver/in-memory/src/public_api.ts

@@ -1,3 +1,5 @@
 export { DaffInMemoryBackendNavigationService } from './backend/navigation.service';
 export { DaffInMemoryNavigationService } from './navigation.service';
 export { DaffNavigationInMemoryDriverModule } from './navigation-driver.module';
+
+export * from './seed-data-provider/public_api';

libs/navigation/driver/in-memory/src/seed-data-provider/public_api.ts

@@ -0,0 +1,2 @@
+export { DaffNavigationInMemorySeedDataProvider } from './type';
+export * from './token';

libs/navigation/driver/in-memory/src/seed-data-provider/token.ts

@@ -0,0 +1,21 @@
+import {
+  InjectionToken,
+  ValueProvider,
+} from '@angular/core';
+
+import { DaffNavigationInMemorySeedDataProvider } from './type';
+
+/**
+ * A token for providing a way for the navigation in-memory driver to seed its data from an external source.
+ */
+export const DAFF_NAVIGATION_IN_MEMORY_SEED_DATA_PROVIDER = new InjectionToken<DaffNavigationInMemorySeedDataProvider>('DAFF_NAVIGATION_IN_MEMORY_SEED_DATA_PROVIDER');
+
+/**
+ * Provides {@link DAFF_NAVIGATION_IN_MEMORY_SEED_DATA_PROVIDER}.
+ */
+export function daffProvideNavigationInMemorySeedDataProvider(provider: DaffNavigationInMemorySeedDataProvider): ValueProvider {
+  return {
+    provide: DAFF_NAVIGATION_IN_MEMORY_SEED_DATA_PROVIDER,
+    useValue: provider,
+  };
+}

libs/navigation/driver/in-memory/src/seed-data-provider/type.ts

@@ -0,0 +1,6 @@
+import { DaffNavigationTree } from '@daffodil/navigation';
+
+/**
+ * A function that fetches and returns the root navigation tree for the in-memory driver.
+ */
+export type DaffNavigationInMemorySeedDataProvider = () => DaffNavigationTree;