boot.js

import { Pool } from 'pg';

async function createPostgrePool(config, app, clientName = 'default') {
  app.coreLogger.info(
    '[egg-postgresql] clientName[%s] connecting %s@%s:%s/%s',
    clientName,
    config.user,
    config.host,
    config.port,
    config.database
  );

  const client = new Pool(config);

  const { rows } = await client.query('SELECT NOW() AS currentTime;');
  app.coreLogger.info(
    '[egg-postgresql] clientName[%s] status OK, PostgreSQL Server currentTime: %j',
    clientName,
    rows[0].currentTime
  );

  return client;
}

export class PostgreSQLBootHook {
  constructor(app) {
    this.app = app;
  }

  configDidLoad() {
    if (this.app.type === 'application' && !this.app.config.postgresql.app) {
      return;
    } else if (this.app.type === 'agent' && !this.app.config.postgresql.agent) {
      return;
    }

    this.app.addSingleton('postgresql', createPostgrePool);
    // alias to `app.pg`
    Reflect.defineProperty(this.app, 'pg', {
      get() {
        return this.postgresql;
      },
    });
  }
}