feat: implement Dynamic Modules support (sync and async)

Allows modules to be configured at runtime via static methods returning DynamicModule objects, similar to NestJS forRoot/register patterns.

src/container/Container.ts

@@ -2,8 +2,10 @@ import "reflect-metadata";
 import { CircularDependencyError, ProviderNotFoundError } from "../errors";
 import { ContextualModuleRef, ModuleRef } from "../module/ModuleRef";
 import type { Constructor } from "../types";
+import type { ForwardRefFn } from "./forwardRef";
 import {
 	type BaseProvider,
+	type DynamicModule,
 	INJECT_METADATA_KEY,
 	INJECTABLE_METADATA_KEY,
 	MODULE_METADATA_KEY,
@@ -40,34 +42,95 @@ export class Container {
 		this.ensureScope(this.globalContext);
 	}
 
-	public registerRootModule(moduleClass: Constructor): void {
-		this.rootModuleName = moduleClass.name;
-		this.registerModule(moduleClass);
+	public async registerRootModule(
+		module: Constructor | DynamicModule,
+	): Promise<void> {
+		const moduleClass = (module as DynamicModule).module || module;
+		this.rootModuleName = (moduleClass as Constructor).name;
+		await this.registerModule(module);
 	}
 
 	public getRootModuleName(): string | undefined {
 		return this.rootModuleName;
 	}
 
-	public registerModule(moduleClass: Constructor): void {
-		const options: ModuleOptions | undefined = Reflect.getMetadata(
+	public async registerModule(
+		module:
+			| Constructor
+			| DynamicModule
+			| Promise<DynamicModule>
+			| ForwardRefFn<Constructor>,
+	): Promise<void> {
+		const unwrappedModule = (await (typeof module === "object" &&
+		module !== null &&
+		"forwardRef" in (module as object)
+			? (
+					module as { forwardRef: () => Constructor | DynamicModule }
+				).forwardRef()
+			: module)) as Constructor | DynamicModule;
+
+		const isDynamic =
+			typeof unwrappedModule === "object" && "module" in unwrappedModule;
+		const moduleClass = isDynamic
+			? (unwrappedModule as DynamicModule).module
+			: (unwrappedModule as Constructor);
+		const dynamicOptions: ModuleOptions = isDynamic
+			? (unwrappedModule as DynamicModule)
+			: {};
+
+		const metadataOptions: ModuleOptions | undefined = Reflect.getMetadata(
 			MODULE_METADATA_KEY,
 			moduleClass,
 		);
-		if (!options) return;
+
+		if (!metadataOptions && !isDynamic) return;
 
 		const moduleName = moduleClass.name;
 		if (this.moduleOptions.has(moduleName)) return;
 
+		const rawImports = [
+			...(metadataOptions?.imports || []),
+			...(dynamicOptions?.imports || []),
+		];
+
+		const resolvedImports = await Promise.all(
+			rawImports.map(async (imp) => {
+				return await (typeof imp === "object" &&
+				imp !== null &&
+				"forwardRef" in (imp as object)
+					? (
+							imp as {
+								forwardRef: () => Constructor | DynamicModule;
+							}
+						).forwardRef()
+					: imp);
+			}),
+		);
+
+		const options: ModuleOptions = {
+			...metadataOptions,
+			...dynamicOptions,
+			imports: resolvedImports,
+			providers: [
+				...(metadataOptions?.providers || []),
+				...(dynamicOptions?.providers || []),
+			],
+			exports: [
+				...(metadataOptions?.exports || []),
+				...(dynamicOptions?.exports || []),
+			],
+		};
+
 		this.moduleOptions.set(moduleName, options);
 		this.ensureScope(moduleName);
 
-		if (options.imports) {
-			for (const imported of options.imports) {
-				this.registerModule(
-					this.unwrapToken(imported as ProviderToken<Constructor>),
-				);
-			}
+		for (const imported of resolvedImports) {
+			await this.registerModule(
+				imported as
+					| Constructor
+					| DynamicModule
+					| Promise<DynamicModule>,
+			);
 		}
 
 		if (options.providers) {
@@ -292,15 +355,16 @@ export class Container {
 		const options = this.moduleOptions.get(context);
 		if (options?.imports) {
 			for (const imported of options.imports) {
-				const unwrappedImport = this.unwrapToken(
-					imported as ProviderToken<Constructor>,
-				);
-				const importedProviders = this.providers.get(
-					unwrappedImport.name,
-				);
-				const importedOptions = this.moduleOptions.get(
-					unwrappedImport.name,
-				);
+				const importedModule =
+					(imported as DynamicModule).module ||
+					(imported as Constructor);
+
+				if (typeof importedModule !== "function") continue;
+
+				const moduleName = importedModule.name;
+				const importedProviders = this.providers.get(moduleName);
+				const importedOptions = this.moduleOptions.get(moduleName);
+
 				if (
 					importedProviders?.has(unwrappedToken) &&
 					importedOptions?.exports?.some(
@@ -310,7 +374,7 @@ export class Container {
 				) {
 					return importedProviders.get(unwrappedToken);
 				}
-				if (unwrappedToken === unwrappedImport) {
+				if (unwrappedToken === importedModule) {
 					return importedProviders?.get(unwrappedToken);
 				}
 			}

src/container/types.ts

@@ -53,8 +53,17 @@ export interface InjectableOptions {
 	scope?: ProviderScope;
 }
 
+export interface DynamicModule extends ModuleOptions {
+	module: Constructor;
+}
+
 export interface ModuleOptions {
-	imports?: (Constructor | ForwardRefFn<Constructor>)[];
+	imports?: (
+		| Constructor
+		| DynamicModule
+		| Promise<DynamicModule>
+		| ForwardRefFn<Constructor>
+	)[];
 	providers?: Provider[];
 	exports?: ProviderToken[];
 }

src/factory/AlveoFactory.ts

@@ -1,4 +1,5 @@
 import { Container } from "../container/Container";
+import type { DynamicModule } from "../container/types";
 import type { Constructor } from "../types";
 import { AlveoApplication } from "./AlveoApplication";
 
@@ -13,11 +14,13 @@ export class AlveoFactoryStatic {
 	 * @param rootModule The root module of the application.
 	 * @returns A promise that resolves to an AlveoApplication instance.
 	 */
-	public async create(rootModule: Constructor): Promise<AlveoApplication> {
+	public async create(
+		rootModule: Constructor | DynamicModule,
+	): Promise<AlveoApplication> {
 		const container = new Container();
 
 		// 1. Register the module tree starting from the root module
-		container.registerRootModule(rootModule);
+		await container.registerRootModule(rootModule);
 
 		// 2. Resolve all providers (this builds the graph and instantiates singletons)
 		await container.resolveAll();

test/container.test.ts

@@ -141,7 +141,7 @@ describe("Alveo Container & DI", () => {
 		// We use a fresh container to test concurrent resolution
 		// bypassing the sequential resolveAll() of AlveoFactory.create()
 		const container = new Container();
-		container.registerRootModule(RootModule);
+		await container.registerRootModule(RootModule);
 
 		const [val1, val2] = await Promise.all([
 			container.get(TOKEN),
@@ -308,4 +308,69 @@ describe("Alveo Container & DI", () => {
 		expect(aliased).toBe(real);
 		expect((aliased as RealService).ok()).toBe(true);
 	});
+
+	test("should support Synchronous Dynamic Modules", async () => {
+		@Injectable()
+		class DynamicService {
+			constructor(@Inject("CONFIG") public readonly config: string) {}
+		}
+
+		@Module({})
+		class DynamicModule {
+			static forRoot(config: string) {
+				return {
+					module: DynamicModule,
+					providers: [
+						DynamicService,
+						{ provide: "CONFIG", useValue: config },
+					],
+					exports: [DynamicService],
+				};
+			}
+		}
+
+		@Module({
+			imports: [DynamicModule.forRoot("dynamic_config")],
+		})
+		class AppModule {}
+
+		const app = await AlveoFactory.create(AppModule);
+		const service = await app.get(DynamicService);
+
+		expect(service.config).toBe("dynamic_config");
+	});
+
+	test("should support Asynchronous Dynamic Modules", async () => {
+		@Injectable()
+		class AsyncDynamicService {
+			constructor(
+				@Inject("ASYNC_CONFIG") public readonly config: string,
+			) {}
+		}
+
+		@Module({})
+		class AsyncDynamicModule {
+			static async forRoot(config: string) {
+				await new Promise((resolve) => setTimeout(resolve, 10));
+				return {
+					module: AsyncDynamicModule,
+					providers: [
+						AsyncDynamicService,
+						{ provide: "ASYNC_CONFIG", useValue: config },
+					],
+					exports: [AsyncDynamicService],
+				};
+			}
+		}
+
+		@Module({
+			imports: [AsyncDynamicModule.forRoot("async_dynamic_config")],
+		})
+		class AppModule {}
+
+		const app = await AlveoFactory.create(AppModule);
+		const service = await app.get(AsyncDynamicService);
+
+		expect(service.config).toBe("async_dynamic_config");
+	});
 });