Dependency Injection Setup

DomusJS uses tsyringe as its dependency injection (DI) container.
The infrastructure module provides the registerDomusCore() helper to simplify and centralize the registration of core dependencies.

✅ This ensures that buses, loggers, and other infrastructure services are available across your app without manual wiring.

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What Does registerDomusCore() Do?

The registerDomusCore() function:

• Registers the CommandBus, QueryBus, and EventBus (default: in-memory versions).
• Registers the Logger implementation you provide.
• Registers shared utilities like unique ID providers.
• Prepares the DI container (tsyringe) for application use.

✅ This sets up all core services before you register additional bounded contexts or modules.

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Basic Setup

import { registerDomusCore, PinoLogger } from '@domusjs/infrastructure';

registerDomusCore({
  logger: new PinoLogger()
});

✅ After this call, you can resolve buses, loggers, and core services anywhere in your app:

const commandBus = container.resolve<CommandBus>('CommandBus');
const logger = container.resolve<Logger>('Logger');

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Customizing the Buses

While registerDomusCore() sets up in-memory buses by default, you can easily override them with your own implementations or switch to other provided DomusJS integrations as needed:

import {
  registerDomusCore,
  PinoLogger,
  RabbitMQEventBus
} from '@domusjs/infrastructure';
import { MyCommandBusImplementation } from './command-bus';
import { MyQueryBusImplementation } from './query-bus';

registerDomusCore({
  logger: new PinoLogger(),
  commandBus: new MyCommandBusImplementation(),
  queryBus: new MyQueryBusImplementation(),
  eventBus: new RabbitMQEventBus(),
});

✅ This keeps the default setup minimal but fully extensible.

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Registering Additional Dependencies

While registerDomusCore() handles the core setup (buses, logger, etc.), you’ll often need to register other services or repositories that are specific to your application.

✅ You can register these outside the core helper by using the tsyringe container directly:

import { container } from 'tsyringe';
import { UserRepository } from './repositories/user-repository';
import { PrismaUserRepository } from './repositories/prisma-user-repository';

container.register<UserRepository>('UserRepository', {
  useClass: PrismaUserRepository,
});

✅ This pattern allows you to wire up bounded context dependencies, infrastructure services, or any custom components.

ℹ️ Tip:
Always call registerDomusCore() first, so the shared core services are ready before you add additional registrations.

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Best Practices

✅ Centralize all DI setup inside your main registerDependencies() function or module.
✅ Always call registerDomusCore() before registering bounded contexts or application-specific services.
✅ Keep bus and logger implementations swappable by sticking to the defined interfaces.
✅ Avoid leaking infrastructure-specific classes into the domain layer.

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Learn More

• tsyringe Documentation