implemented a simple backend for mobile banking

src/server.js

@@ -0,0 +1,22 @@
+const app = require('./app');
+const { port } = require('./config/config');
+const { logger } = require('./util/logger');
+const db = require('./config/db');
+
+const server = app.listen(port, () => {
+  logger.info(`server listening on http://localhost:${port}`);
+});
+
+const shutdown = () => {
+  logger.info('shutting down server...');
+  server.close(() => {
+    logger.info('http server closed');
+    db.pool.end(() => {
+      logger.info('pg pool has ended');
+      process.exit(0);
+    });
+  });
+};
+
+process.on('SIGINT', shutdown);
+process.on('SIGTERM', shutdown);