typeorm 0.3.6 - db connection per request

Question

I’m migrating from 0.2.* to 0.3.6 version of typeorm. I’m not sure how to handle multi-tenant connections with new DataSource. My previous implementations was based on connectionManager and it looked something like this:

{
    const connectionManager = getConnectionManager();

    // Check if tenant connection exists
    if (connectionManager.has(tenant.name)) {
      const connection = connectionManager.get(tenant.name);
      return Promise.resolve(
        connection.isConnected ? connection : connection.connect()
      );
    }

    // Create new tenant connection
    return createConnection({
      type: 'postgres',
      name: tenant.name,
      host: tenant.host,
      port: tenant.port,
      username: tenant.username,
      password: tenant.password,
      database: tenant.database,
      entities: [...TenantModule.entities],
    });
}

Connection manger is now deprecated. Maintaining my own array of connections doesn’t sound right to me. Any ideas on how this should be handled the correct way?

Answer 1

with typeorm: 0.3.6 getConnection, createConnection among others are deprecated. You can find migration guide in here

to create a new connection, you will have to use DataSource as follows:

import { DataSource, DataSourceOptions } from 'typeorm';

const dataSourceOptions: DataSourceOptions = {
  type: 'mysql',
  host,
  port,
  username,
  password,
  database,
  synchronize: false,
  logging: false,
  entities: ['src/database/entity/*.ts'],
  migrations: ['src/database/migration/*.ts'],
};

export const AppDataSource = new DataSource(dataSourceOptions);

where new DataSource is equivalent to new Connection and dataSource is equal to getConnection.

To check if you are connection to database, you will have utilize AppDataSource:

AppDataSource.initialize()
  .then(() => {
    // db initialized
  })
  .catch((err: Error) => {
    throw new Error(`'Database connection error: ${err}`);
  });