Nest TypeORM example

Example usage of TypeORM with the Nest framework.

Overview

• TypeORM is implemented by the database Nest module, the same as any other piece of user code should be in a Nest application.
• The database module defines the injectable service TypeOrmDatabaseService which can be used to access the TypeORM repositories or EntityManager.
• Additional ORM's such as Mongoose could be implemented in this module easily by simply defining additional services which manage configuration and connection.
• The interface Service<T> is provided for loose coupling between controllers and services, so you'll see use of it in the examples.
• TypeORM is configured to find and manage all entities under src/modules, so just name your entities anything.entity.ts and TypeORM will pick them up.
• TypeORM's autosync is on by default so the db schema will be updated automatically by TypeORM.

Examples

Service:

@Component()
export class EmployeesService implements Service<Employee> {
    constructor(private databaseService: TypeOrmDatabaseService) {}
    
    private get repository(): Promise<Repository<Employee>> {
        return this.databaseService.getRepository(Employee);
    }
        
    public async getAll(): Promise<Employee[]> {
        return (await this.repository).find();
    }
    
    ...
}

Controller:

@Controller()
export class EmployeesController {
    private employeesService: Service<Employee>;

    constructor(employeesService: EmployeesService) {
        this.employeesService = employeesService;
    }
    
    @Get('employees')
    public async getAllEmployees(@Request() req, @Response() res: express.Response) {
        const employees = await this.employeesService.getAll();
        res.status(HttpStatus.OK).json(employees);
    }
    
    ...
}

Installation

$ npm i

Configuration

The server app and TypeORM implementation must be configured via env variables.

Here's an example configuration which assumes a MySQL server is running locally:

PORT=3000
DB_DRIVER=mysql
DB_USERNAME=test
DB_PASSWORD=test
DB_HOST=127.0.0.1
DB_PORT=3306
DB_NAME=nest

Start

$ npm start