@vytches/ddd-nestjs

NestJS integration for VytchesDDD.

Installation

pnpm add @vytches/ddd-nestjs @nestjs/common @nestjs/core reflect-metadata rxjs

What's included

| Export | Kind | Description | | ------------------------- | --------- | -------------------------------------------------------------------------------- | | VytchesDDDModule | class | NestJS dynamic module — call VytchesDDDModule.forRoot(options) | | VytchesExplorerService | class | Auto-discovers and registers CQRS / event handlers via NestJS DiscoveryService | | NestJSContainerAdapter | class | Bridges NestJS ModuleRef to the IDependencyContainer interface | | ACLAdapterFor | decorator | Marks a class as an ACL adapter so VytchesExplorerService can discover it | | ACL_REGISTRY | constant | NestJS injection token for the ACLRegistry | | VytchesDDDModuleOptions | interface | Options accepted by VytchesDDDModule.forRoot() | | HandlerInfo | interface | Metadata shape returned by the explorer | | ACLAdapterMetadata | interface | Metadata stored by the @ACLAdapterFor decorator |

Quick start

import { Module } from '@nestjs/common';
import { VytchesDDDModule } from '@vytches/ddd-nestjs';
import {
  EnhancedCommandBus,
  EnhancedQueryBus,
  ICommandBus,
  IQueryBus,
} from '@vytches/ddd-cqrs';
import { UnifiedEventBus, IEventBus } from '@vytches/ddd-events';

@Module({
  imports: [
    VytchesDDDModule.forRoot({
      providers: [
        { provide: ICommandBus, useClass: EnhancedCommandBus },
        { provide: IQueryBus, useClass: EnhancedQueryBus },
        { provide: IEventBus, useClass: UnifiedEventBus },
      ],
    }),
  ],
})
export class AppModule {}

VytchesDDDModule.forRoot

The only static factory method available. Accepts VytchesDDDModuleOptions:

interface VytchesDDDModuleOptions {
  providers?: Provider[]; // bus implementations, adapters, etc.
  imports?: any[]; // additional NestJS modules to import
  exports?: any[]; // additional symbols to export
}

VytchesExplorerService is always exported and can be injected into any NestJS provider to query discovered handler metadata.

Handler auto-discovery

VytchesExplorerService uses NestJS DiscoveryService to find classes decorated with @CommandHandler, @QueryHandler (from @vytches/ddd-cqrs), @EventHandler (from @vytches/ddd-events), and @ACLAdapterFor (this package). Discovery runs during onModuleInit.

import { Controller, Get } from '@nestjs/common';
import { VytchesExplorerService } from '@vytches/ddd-nestjs';

@Controller('debug')
export class DebugController {
  constructor(private readonly explorer: VytchesExplorerService) {}

  @Get('handlers')
  listHandlers() {
    return this.explorer.getHandlers(); // HandlerInfo[]
  }
}

ACL adapter registration

import { ACLAdapterFor } from '@vytches/ddd-nestjs';
import { Injectable } from '@nestjs/common';
import { SimpleACLAdapter } from '@vytches/ddd-acl';

@Injectable()
@ACLAdapterFor('PaymentsContext')
export class PaymentsACLAdapter extends SimpleACLAdapter<
  Order,
  ExternalPayment
> {
  // ...
}

The explorer discovers all @ACLAdapterFor-decorated classes and registers them in the ACLRegistry provided under the ACL_REGISTRY token.

Package boundaries

@vytches/ddd-nestjs depends on:

• @nestjs/common, @nestjs/core — peer dependencies
• @vytches/ddd-cqrs — ICommandBus, IQueryBus, handler metadata
• @vytches/ddd-events — IEventBus, EventHandler metadata
• @vytches/ddd-acl — ACLRegistry
• @vytches/ddd-di — IDependencyContainer

License

MIT