server.ts

import config from 'config';
import logger from './utils/logger';
import * as http from 'http';
import app from './app';
import { version } from './package.json';
import ErrnoException = NodeJS.ErrnoException;
import checkDatabaseConnection from './utils/prisma';
import { env } from 'process';

// Initialise globals
global.config = config;
global.logger = logger;

const port: number = config.get('port');
app.set('port', port);

/**
 * Create HTTP server.
 */

const server = http.createServer(app);

/**
 * Listen on provided port, on all network interfaces.
 */

server.listen(port);
server.on('error', onError);
server.on('listening', onListening);

if (String(env.NODE_ENV) !== 'test') {
  /**
   * Checks if DB is connected
   */
  void checkDatabaseConnection();
}
/**
 * Event listener for HTTP server "error" event.
 */

function onError(error: ErrnoException): ErrnoException {
  if (error.syscall !== 'listen') {
    throw error;
  }

  const bind = `Port ${port}`;

  // handle specific listen errors with friendly messages
  switch (error.code) {
    case 'EACCES':
      logger.error(bind + ' requires elevated privileges');
      process.exit(1);
      // eslint-disable-next-line no-unreachable
      break;

    case 'EADDRINUSE':
      logger.error(bind + ' is already in use');
      process.exit(1);
      // eslint-disable-next-line no-unreachable
      break;

    default:
      throw error;
  }
}

/**
 * Event listener for HTTP server "listening" event.
 */

function onListening(): void {
  logger.info(
    `Express API running on port:${port} with environment:${String(
      process.env.NODE_ENV
    )}`,
    { version }
  );
}

export default server;