chore: prep for NestJS 12 (deep-import removal, dual ESM/CJS, Vitest)

package.json

@@ -36,15 +36,14 @@
 		"@nestjs/testing": "11.1.6",
 		"@swc-node/register": "^1.11.1",
 		"@swc/core": "1.13.5",
-		"@swc/jest": "0.2.39",
-		"@types/jest": "30.0.0",
 		"@types/node": "22.13.4",
-		"jest": "30.1.3",
-		"jest-mock": "30.0.5",
+		"@vitest/coverage-v8": "^4.0.0",
 		"reflect-metadata": "0.2.2",
 		"rxjs": "7.8.2",
 		"turbo": "^2.5.6",
-		"typescript": "5.9.2"
+		"typescript": "5.9.2",
+		"unplugin-swc": "^1.5.7",
+		"vitest": "^4.0.0"
 	},
 	"repository": {
 		"type": "git",

packages/config/package.json

@@ -2,5 +2,9 @@
 	"name": "@ocoda/event-sourcing-config",
 	"version": "1.0.0",
 	"private": true,
-	"license": "MIT"
+	"license": "MIT",
+	"exports": {
+		"./vitest/base": "./vitest/base.mjs",
+		"./typescript/*": "./typescript/*"
+	}
 }

packages/config/vitest/base.mjs

@@ -0,0 +1,40 @@
+import swc from 'unplugin-swc';
+import { defineConfig } from 'vitest/config';
+
+export default defineConfig({
+	plugins: [
+		swc.vite({
+			jsc: {
+				parser: { syntax: 'typescript', decorators: true },
+				transform: { legacyDecorator: true, decoratorMetadata: true },
+				target: 'es2016',
+				keepClassNames: true,
+			},
+			module: { type: 'es6' },
+		}),
+	],
+	test: {
+		globals: true,
+		environment: 'node',
+		include: ['tests/**/*.spec.ts'],
+		coverage: {
+			provider: 'v8',
+			reporter: ['text', 'lcov', 'json-summary'],
+			include: ['lib/**/*.ts'],
+			exclude: [
+				'lib/**/*.d.ts',
+				'lib/**/index.ts',
+				'lib/**/*.interface.ts',
+				'lib/**/*.type.ts',
+				'lib/**/*.enum.ts',
+				'lib/**/*.constants.ts',
+			],
+			thresholds: {
+				lines: 90,
+				functions: 90,
+				branches: 80,
+				statements: 90,
+			},
+		},
+	},
+});

packages/core/.npmignore

@@ -11,7 +11,7 @@ tests
 .turbo
 biome.json
 docker-compose.yml
-jest.config.js
+vitest.config.mts
 pnpm-lock.yaml
 renovate.json
 tsconfig.build.json

packages/core/lib/command-bus.ts

@@ -1,6 +1,5 @@
 import 'reflect-metadata';
 import { Injectable, type Type } from '@nestjs/common';
-import type { InstanceWrapper } from '@nestjs/core/injector/instance-wrapper';
 
 import {
 	CommandHandlerNotFoundException,
@@ -9,7 +8,7 @@ import {
 	MissingCommandMetadataException,
 } from './exceptions';
 import { DefaultCommandPubSub, ObservableBus, getCommandHandlerMetadata, getCommandMetadata } from './helpers';
-import type { ICommand, ICommandBus, ICommandHandler, ICommandPublisher } from './interfaces';
+import type { ICommand, ICommandBus, ICommandHandler, ICommandPublisher, ProviderWrapper } from './interfaces';
 
 @Injectable()
 export class CommandBus<CommandBase extends ICommand = ICommand>
@@ -50,12 +49,12 @@ export class CommandBus<CommandBase extends ICommand = ICommand>
 		return id;
 	}
 
-	register(handlers: InstanceWrapper<ICommandHandler>[] = []) {
+	register(handlers: ProviderWrapper<ICommandHandler>[] = []) {
 		for (const handler of handlers) {
 			this.registerHandler(handler);
 		}
 	}
-	protected registerHandler(handler: InstanceWrapper<ICommandHandler>) {
+	protected registerHandler(handler: ProviderWrapper<ICommandHandler>) {
 		// get the metadata from the handler
 		const { metatype, instance } = handler;
 

packages/core/lib/event-bus.ts

@@ -1,12 +1,11 @@
 import { Injectable, type OnModuleDestroy, type Type } from '@nestjs/common';
-import type { InstanceWrapper } from '@nestjs/core/injector/instance-wrapper';
 import { type Observable, type Subscription, from } from 'rxjs';
 import { filter, mergeMap } from 'rxjs/operators';
 
 import { MissingEventMetadataException, MissingEventSubscriberMetadataException } from './exceptions';
 import { ObservableBus, getEventMetadata, getEventSubscriberMetadata } from './helpers';
 import { DefaultEventPubSub } from './helpers/default-event-publisher';
-import type { IEventBus, IEventPublisher, IEventSubscriber } from './interfaces';
+import type { IEventBus, IEventPublisher, IEventSubscriber, ProviderWrapper } from './interfaces';
 import type { EventEnvelope } from './models';
 
 @Injectable()
@@ -46,24 +45,24 @@ export class EventBus extends ObservableBus<EventEnvelope> implements IEventBus,
 		return this.subject$.pipe(filter(({ event }) => event === eventName));
 	}
 
-	registerPublishers(publishers: InstanceWrapper<IEventPublisher>[] = []) {
+	registerPublishers(publishers: ProviderWrapper<IEventPublisher>[] = []) {
 		for (const publisher of publishers) {
 			this.registerPublisher(publisher);
 		}
 	}
-	registerSubscribers(subscribers: InstanceWrapper<IEventSubscriber>[] = []) {
+	registerSubscribers(subscribers: ProviderWrapper<IEventSubscriber>[] = []) {
 		for (const subscriber of subscribers) {
 			this.registerSubscriber(subscriber);
 		}
 	}
 
-	protected registerPublisher(handler: InstanceWrapper<IEventPublisher>) {
+	protected registerPublisher(handler: ProviderWrapper<IEventPublisher>) {
 		const { instance } = handler;
 		if (!instance) return;
 
 		this.addPublisher(instance as IEventPublisher);
 	}
-	protected registerSubscriber(handler: InstanceWrapper<IEventSubscriber>) {
+	protected registerSubscriber(handler: ProviderWrapper<IEventSubscriber>) {
 		const { metatype, instance } = handler;
 		if (!metatype || !instance) {
 			throw new MissingEventSubscriberMetadataException(metatype as Type<IEventSubscriber>);

packages/core/lib/event-map.ts

@@ -1,12 +1,11 @@
 import { Injectable, type Type } from '@nestjs/common';
-import type { InstanceWrapper } from '@nestjs/core/injector/instance-wrapper';
 import {
 	MissingEventMetadataException,
 	UnregisteredEventException,
 	UnregisteredSerializerException,
 } from './exceptions';
 import { DefaultEventSerializer, getEventMetadata, getEventSerializerMetadata } from './helpers';
-import type { IEvent, IEventPayload, IEventSerializer } from './interfaces';
+import type { IEvent, IEventPayload, IEventSerializer, ProviderWrapper } from './interfaces';
 
 export type EventSerializerType = Type<IEventSerializer<IEvent>>;
 
@@ -95,7 +94,7 @@ export class EventMap {
 		return name;
 	}
 
-	registerSerializers(events: Type<IEvent>[] = [], serializers: InstanceWrapper<IEventSerializer>[] = []) {
+	registerSerializers(events: Type<IEvent>[] = [], serializers: ProviderWrapper<IEventSerializer>[] = []) {
 		for (const event of events) {
 			// get the handler
 			const handler = serializers.find(({ metatype }) => {

packages/core/lib/interfaces/index.ts

@@ -2,4 +2,5 @@ export type * from './aggregate';
 export type * from './commands';
 export type * from './events';
 export type * from './module';
+export type * from './provider-wrapper';
 export type * from './queries';

packages/core/lib/interfaces/provider-wrapper.ts

@@ -0,0 +1,5 @@
+import type { DiscoveryService } from '@nestjs/core';
+
+export type ProviderWrapper<T = unknown> = ReturnType<DiscoveryService['getProviders']>[number] & {
+	instance?: T;
+};

packages/core/lib/query-bus.ts

@@ -1,6 +1,5 @@
 import 'reflect-metadata';
 import { Injectable, type Type } from '@nestjs/common';
-import type { InstanceWrapper } from '@nestjs/core/injector/instance-wrapper';
 
 import {
 	InvalidQueryHandlerException,
@@ -9,7 +8,7 @@ import {
 	QueryHandlerNotFoundException,
 } from './exceptions';
 import { DefaultQueryPubSub, ObservableBus, getQueryHandlerMetadata, getQueryMetadata } from './helpers';
-import type { IQuery, IQueryBus, IQueryHandler, IQueryPublisher } from './interfaces';
+import type { IQuery, IQueryBus, IQueryHandler, IQueryPublisher, ProviderWrapper } from './interfaces';
 
 @Injectable()
 export class QueryBus<QueryBase extends IQuery = IQuery>
@@ -53,12 +52,12 @@ export class QueryBus<QueryBase extends IQuery = IQuery>
 		return id;
 	}
 
-	register(handlers: InstanceWrapper<IQueryHandler>[] = []) {
+	register(handlers: ProviderWrapper<IQueryHandler>[] = []) {
 		for (const handler of handlers) {
 			this.registerHandler(handler);
 		}
 	}
-	protected registerHandler(handler: InstanceWrapper<IQueryHandler>) {
+	protected registerHandler(handler: ProviderWrapper<IQueryHandler>) {
 		const { metatype, instance } = handler;
 
 		// check

packages/core/lib/services/explorer.service.ts

@@ -1,9 +1,6 @@
 import { Injectable, type Type } from '@nestjs/common';
-import type { InstanceWrapper } from '@nestjs/core/injector/instance-wrapper';
-
-import type { Module } from '@nestjs/core/injector/module';
 // biome-ignore lint/style/useImportType: DI
-import { ModulesContainer } from '@nestjs/core/injector/modules-container';
+import { DiscoveryService } from '@nestjs/core';
 
 import {
 	COMMAND_HANDLER_METADATA,
@@ -21,6 +18,7 @@ import type {
 	IEventSerializer,
 	IEventSubscriber,
 	IQueryHandler,
+	ProviderWrapper,
 } from '../interfaces';
 import { EventRegistry } from '../registries';
 
@@ -29,73 +27,51 @@ export type ProvidersIntrospectionResult = {
 	 * For future saga support, currently unused.
 	 * @ignore
 	 */
-	sagas?: InstanceWrapper[];
+	sagas?: ProviderWrapper[];
 	events?: Type<IEvent>[];
-	queries?: InstanceWrapper<IQueryHandler>[];
-	commands?: InstanceWrapper<ICommandHandler>[];
-	eventPublishers?: InstanceWrapper<IEventPublisher>[];
-	eventSubscribers?: InstanceWrapper<IEventSubscriber>[];
-	eventSerializers?: InstanceWrapper<IEventSerializer>[];
+	queries?: ProviderWrapper<IQueryHandler>[];
+	commands?: ProviderWrapper<ICommandHandler>[];
+	eventPublishers?: ProviderWrapper<IEventPublisher>[];
+	eventSubscribers?: ProviderWrapper<IEventSubscriber>[];
+	eventSerializers?: ProviderWrapper<IEventSerializer>[];
 };
 
 @Injectable()
 export class ExplorerService {
 	constructor(
 		@InjectEventSourcingOptions()
 		private readonly options: EventSourcingModuleOptions,
-		private readonly modulesContainer: ModulesContainer,
+		private readonly discoveryService: DiscoveryService,
 	) {}
 
 	get events(): Type<IEvent>[] {
 		return [...(this.options.events ?? []), ...EventRegistry.getEvents()];
 	}
 
 	explore(): ProvidersIntrospectionResult {
-		const modules = [...this.modulesContainer.values()];
+		const providers = this.discoveryService.getProviders();
 
 		return {
 			sagas: [],
 			events: this.events,
-			queries: this.flatMap<IQueryHandler>(modules, (instance) =>
-				this.filterByMetadataKey(instance, QUERY_HANDLER_METADATA),
-			),
-			commands: this.flatMap<ICommandHandler>(modules, (instance) =>
-				this.filterByMetadataKey(instance, COMMAND_HANDLER_METADATA),
-			),
-			eventPublishers: this.flatMap<IEventPublisher>(modules, (instance) =>
-				this.filterByMetadataKey(instance, EVENT_PUBLISHER_METADATA),
-			),
-			eventSubscribers: this.flatMap<IEventSubscriber>(modules, (instance) =>
-				this.filterByMetadataKey(instance, EVENT_SUBSCRIBER_METADATA),
-			),
-			eventSerializers: this.flatMap<IEventSerializer>(modules, (instance) =>
-				this.filterByMetadataKey(instance, EVENT_SERIALIZER_METADATA),
-			),
+			queries: this.filterByMetadataKey<IQueryHandler>(providers, QUERY_HANDLER_METADATA),
+			commands: this.filterByMetadataKey<ICommandHandler>(providers, COMMAND_HANDLER_METADATA),
+			eventPublishers: this.filterByMetadataKey<IEventPublisher>(providers, EVENT_PUBLISHER_METADATA),
+			eventSubscribers: this.filterByMetadataKey<IEventSubscriber>(providers, EVENT_SUBSCRIBER_METADATA),
+			eventSerializers: this.filterByMetadataKey<IEventSerializer>(providers, EVENT_SERIALIZER_METADATA),
 		};
 	}
 
-	flatMap<T extends object>(
-		modules: Module[],
-		callback: (instance: InstanceWrapper) => InstanceWrapper | undefined,
-	): InstanceWrapper<T>[] {
-		const items = modules
-			.map((moduleRef) => [...moduleRef.providers.values()].map(callback))
-			.reduce((a, b) => a.concat(b), []);
-		return items.filter((item) => !!item) as InstanceWrapper<T>[];
-	}
-
-	filterByMetadataKey(wrapper: InstanceWrapper, metadataKey: string) {
-		const { instance } = wrapper;
-		if (!instance) {
-			return;
-		}
-		if (!instance.constructor) {
-			return;
-		}
-		const metadata = Reflect.getMetadata(metadataKey, instance.constructor);
-		if (!metadata) {
-			return;
-		}
-		return wrapper;
+	private filterByMetadataKey<T extends object>(
+		providers: ProviderWrapper[],
+		metadataKey: string,
+	): ProviderWrapper<T>[] {
+		return providers.filter((wrapper) => {
+			const instance = wrapper.instance;
+			if (!instance || !instance.constructor) {
+				return false;
+			}
+			return !!Reflect.getMetadata(metadataKey, instance.constructor);
+		}) as ProviderWrapper<T>[];
 	}
 }