naming and getting a particular connection in typeorm - postgresql

Question

Previously, typeorm seems to have allowed the use of a ConnectionManager that seems to have allowed to name a particular connection whilst creation and fetch/check the connection with the same name like this:
import { Connection, createConnection, getConnectionManager } from 'typeorm';
import { PostgresConnectionOptions } from 'typeorm/driver/postgres/PostgresConnectionOptions';
import * as tenantsOrmconfig from '../../tenants-orm.config';
export function getTenantConnection(tenantId: string): Promise<Connection> {
const connectionName = `tenant_${tenantId}`;
const connectionManager = getConnectionManager();
if (connectionManager.has(connectionName)) {
const connection = connectionManager.get(connectionName);
return Promise.resolve(connection.isConnected ? connection : connection.connect());
}
return createConnection({
...(tenantsOrmconfig as PostgresConnectionOptions),
name: connectionName,
schema: connectionName,
});
}
But, I'm confused now as to how to achieve this when I'm using a Datasource using a factory to create dynamic connection:
#Module({
imports: [
ConfigModule.forRoot({ isGlobal: true }),
TypeOrmModule.forRootAsync({
imports: [ConfigModule],
inject: [ConfigService],
useFactory: (configService: ConfigService) => {
const host = configService.get('MY_DB_HOST');
const port = parseInt(configService.get('MY_DB_PORT'));
const user = configService.get('MY_DB_USER');
const password = configService.get('MY_DB_PASSWORD');
const dbName = configService.get('MY_DB_NAME');
return {
type: 'postgres',
host: host,
port: port,
username: user,
password: password,
database: dbName,
entities: entities,
synchronize: true,
};
}
})
],
controllers: [AppController],
providers: [AppService],
})
I'm trying to fetch an existing connection from the connection pool which typeorm is supposed to manage by default if it already exists, and that connection is supposed to belong to a tenant if it exists, else it should create a new connection for the tenant. How do I do this with a Datasource?
I can see that there is a datasourceInstance.manager.find() method, but, that seems to take an Entity which seems to query the database, and I can't find anything more useful in the docs.