Jest + TypeORM + TestContainers

afterEnv.ts

import { setupTypeOrmTestConnection } from '../integrationSetup';

beforeAll(async () => {
  console.log('AFTER ENV SETUP START');
  global.testConn = await setupTypeOrmTestConnection(+process.env.TEST_PG_PORT);
  console.log('AFTER ENV SETUP DONE');
});

afterAll(async () => {
  console.log('AFTER ENV TEARDOWN START');
  await global.testConn.close();
  console.log('AFTER ENV TEARDOWN DONE');
});

globalPostgresSetup.ts

import { setupTestPostgres } from '../integrationSetup';

module.exports = async () => {
  console.log('\nGLOBAL SETUP START');
  const { port, container } = await setupTestPostgres();

  global.testPgContainer = container;

  process.env.TEST_PG_PORT = `${port}`;

  console.log('GLOBAL SETUP END');
};

globalPostgresTeardown.ts

module.exports = async () => {
  console.log('GLOBAL TEARDOWN START');

  await global.testPgContainer.stop();

  console.log('GLOBAL TEARDOWN END');
};

integrationSetup.ts

import 'reflect-metadata';
import { GenericContainer, StartedTestContainer } from 'testcontainers';
import { ConnectionOptions, Connection, createConnection } from 'typeorm';
import { connectionOptions } from '../../infra/db';

const TEST_DB_NAME = 'playground_test';
const PG_USER = 'postgres';

export interface TestContainerData {
  container: StartedTestContainer;
  port: number;
}

export const setupTestPostgres = async (): Promise<TestContainerData> => {
  const PG_PORT = 5432;
  const pgContainer = new GenericContainer('postgres', '12.1')
    .withExposedPorts(PG_PORT)
    .withEnv('POSTGRES_USER', PG_USER)
    .withEnv('POSTGRES_DB', TEST_DB_NAME);
  const pgContainerStarted = await pgContainer.start();
  const containerPort = pgContainerStarted.getMappedPort(PG_PORT);

  console.log(`test Postgres port: ${containerPort}`);

  return {
    container: pgContainerStarted,
    port: containerPort,
  };
};

export const setupTypeOrmTestConnection = async (pgPort?: number): Promise<Connection> => {
  let port = pgPort as number;

  if (!pgPort) {
    const { port: containerPort } = await setupTestPostgres();

    port = containerPort;
  }

  const opts = getTestDatabaseConnectionOptions(port);


  const connection = await createConnection(opts);
  await connection.runMigrations();
  return connection;
};

export const getTestDatabaseConnectionOptions = (
  dbPort: number
): ConnectionOptions => ({
  ...connectionOptions,
  host: 'localhost',
  port: dbPort,
  username: 'postgres',
  password: 'postgres',
  database: TEST_DB_NAME,
} as any);

jest.config.js

module.exports = {
  transform: {
    '^.+\\.ts?$': '@swc/jest',
  },
  testRegex: '(/__tests__/.*|(\\.|/)(test|spec))\\.ts?$',
  rootDir: '.',
  collectCoverageFrom: ['**/*.ts', '!demo.ts'],
  testTimeout: 1200000,
  globalSetup: '<rootDir>/hooks/globalPostgresSetup.ts',
  globalTeardown: '<rootDir>/hooks/globalPostgresTeardown.ts',
  setupFilesAfterEnv: ['<rootDir>/hooks/afterEnv.ts']
};

node.d.ts

import { StartedTestContainer } from 'testcontainers';
import { Connection } from 'typeorm';

// Ensure file is treated as a module
export { };

declare global {
  namespace NodeJS {
    interface Global {
      testConn: Connection;
      testPgContainer: StartedTestContainer;
    }
  }
}

package.json

{
  // ...
  "scripts": {
    "test:unit": "jest --verbose ./src/test/unit/*.test.ts --config ./src/test/unit/jest.config.js",
    "test:it": "jest --verbose --runInBand ./src/test/integration/suites/*.test.ts --config ./src/test/integration/jest.config.js"
  },
  "author": "Joanna Liana",
  "license": "ISC",
  "devDependencies": {
    "@swc/jest": "^0.1.4",
    "@types/jest": "^26.0.15",
    "@types/node": "^8.10.66",
    "jest": "^27.0.6",
    "testcontainers": "^6.4.2",
    "typescript": "^4.2.4"
  },
  "dependencies": {
    "pg": "^8.6.0",
    "reflect-metadata": "^0.1.10",
    "typeorm": "0.2.31"
  }
}

A complementary blog post: https://bytesmith.dev/blog/20240305-nestjs-integration-test-with-test-containers/