TypeOrmModule.forRoot - dynamic configuration

[mgamperl]

Hi,

I really like the simplicity of this module but there is one thing I can not understand:
How do you dynamically configure the database connection when using TypeOrmModule.forRoot

@Module({
  imports: [
    TypeOrmModule.forRoot({
      type: 'mysql',
      host: 'localhost',
      port: 3306,
      ...      
    }),
  ],
})

I have a similar ConfigService like the one in https://docs.nestjs.com/techniques/configuration in my application and want to use that for the configuration of the database connection but its embarrassing, I can't find a solution on how to use this configuration in combination with TypeOrmModule.

I know I could do the creation of the connection in a custom provider following https://docs.nestjs.com/recipes/sql-typeorm but isn't there a simpler way which is as convenient as this module?

Thanks for help and thank you for the hard work you all are putting into nestjs I really love it!

[BrunnerLivio]

I used another approach in my project. I basically share the options through the AppModule:

main.ts

const settings = dotenv.parse(fs.readFileSync(filePath));
const app = await NestFactory.create(AppModule.forRoot(settings));
...

app.module.ts

export class AppModule {
    static forRoot(settings: APISettings): DynamicModule {
        return {
            module: AppModule,
            imports: [
                // This module has a ConfigurationService, which
                // does the same as described in the docs
                // but it does not read the env file.
                AppSettingsModule.forRoot(settings),
                DatabaseModule.forRoot(settings),
                ...
            ]
        };
    }
}

database.module.ts

export function getOrmConfig(settings: IDatabaseSettings) {
     return {
            type: 'postgres',
            host: settings.host,
            port: settings.port,
            username: settings.username,
            password: settings.password,
            database: settings.database,
            entities,
            synchronize: true,
            logging: true,
        };
}

export class DatabaseModule {
  public static forRoot(settings: IDatabaseSettings): DynamicModule {
    const ormConfig = getOrmConfig(settings);
    return {
      module: DatabaseModule,
      imports: [
        TypeOrmModule.forRoot(ormConfig)
      ],
      components: [
        DatabaseService,
      ],
      exports: [
        DatabaseService
      ]
    };
  }
}

I think it is a bad idea to read the configuration inside the service as suggested in the docs. For example; I have the use case, that my application should be useable and configureable by npm package (npm i -s my-api). Lets assume my API is called MyAPI. Then the following code would not be feasable, if the configuration is read by a nestjs service.

import { MyAPI } from 'my-api';

// Bootstraps the NestJS configuration and calls await NestFactory.create(AppModule.forRoot(settings));
new MyAPI({ databaseHost: 'postgres', ... }).run();

Thats why I prefer my solution; its more dynamic and modular.

I hope you get what I mean :)

[mgamperl]

This is a really nice approach, I think I will try this for my use case.
Thank you very much!

I'm closing this issue..

[Alexandredc]

I'm facing the same problem.

@BrunnerLivio your approach is ok but I still prefer handle settings with a service.

For now I didn't found a great a solution, I'm using process.env to retrieve settings in this particular case

[BrunnerLivio]

The project I described in my upper comment is now opensourced.

You can checkout the API to see how I solved this issue.
The starting point would be start-api.js. Then you can go down further the rabbit hole in main.ts and app.module.ts.

Good luck. Hit me up if you have any questions :)