In development environement, i’ve used Typeorm in my Nestjs application. I use the forRootAsync in the app.module.ts to import it with injecting ConfigService to use environement variables:

app.module.ts

imports: [
    ConfigModule.forRoot({
      envFilePath: ['.env.local', '.env'],
      isGlobal: true,
    }),
    TypeOrmModule.forRootAsync({
      inject: [ConfigService],
      useFactory: getTypeOrmConfig,
    }),
    // ...
  ]

My Typeorm config is as follows:

typeorm.config.ts

import { ConfigService } from '@nestjs/config';
import { TypeOrmModuleOptions } from '@nestjs/typeorm';

const getTypeOrmConfig = (
  configService: ConfigService,
): TypeOrmModuleOptions => ({
  type: 'mysql',
  host: configService.get('MYSQL_IP'),
  port: configService.get('MYSQL_HOST'),
  username: 'root',
  password: configService.get('MYSQL_ROOT_PASSWORD'),
  database: configService.get('MYSQL_DATABASE'),
  entities: [__dirname + '/**/*.entity{.ts,.js}'],
  synchronize: true, // Set to false in production
});

export default getTypeOrmConfig;

I used this method because my environement variables were not accessible from process.env despite me following all the guidelines to do so.

My problem is that i want to export the DataSource object so that i can use it to run my migrations in the production environment. Since my DataSourceOptions depend on the ConfigService, i don’t know how to do that. Thank you for all your insights.