AutoInjectable

@tsed/di

Usage

import { AutoInjectable } from "@tsed/di";

See /packages/di/src/common/decorators/autoInjectable.ts.

Overview

function AutoInjectable(): <T extends {
    new (...args: any[]): NonNullable<unknown>;
}>(constr: T) => T;

Description

Enable automatic dependency injection for a class constructor.

Automatically resolves and injects constructor dependencies while preserving the ability to manually pass arguments. Useful for classes that need both automatic DI and manual instantiation flexibility.

Usage

import {AutoInjectable} from "@tsed/di";

@AutoInjectable()
class UserService {
  constructor(
    private database: Database,     // Automatically injected
    private logger: Logger,         // Automatically injected
    customConfig?: Config           // Can be passed manually
  ) {}
}

// Automatic injection
const service1 = new UserService();

// Manual override
const service2 = new UserService(customDb, customLogger, {debug: true});

// Partial override (remaining deps auto-injected)
const service3 = new UserService(undefined, undefined, {debug: true});

Behavior

• Automatically resolves dependencies based on TypeScript metadata
• Manual arguments override automatic injection for that position
• undefined arguments trigger automatic injection

new

new (...args: any[]): NonNullable<unknown>;