typedi

import 'reflect-metadata'; import { Container, Service } from 'typedi'; // A service that will be injected @Service() class MailerService { private readonly apiKey: string; constructor() { this.apiKey = process.env.MAILER_API_KEY ?? 'default-api-key'; } sendMail(to: string, subject: string, body: string): void { console.log(`Sending email to ${to} with subject '${subject}' via API Key: ${this.apiKey}`); console.log(`Body: ${body}`); } } // A service that depends on MailerService @Service() class UserService { constructor(private mailer: MailerService) {} registerUser(email: string, username: string): void { console.log(`Registering user: ${username} (${email})`); this.mailer.sendMail(email, 'Welcome!', `Hello ${username}, welcome to our service!`); } } // Get an instance of UserService from the container, which will automatically inject MailerService const userService = Container.get(UserService); userService.registerUser('john.doe@example.com', 'JohnDoe'); // You can also get other services directly const mailerService = Container.get(MailerService); mailerService.sendMail('admin@example.com', 'System Alert', 'Server running fine!');