Fix performance issues with list queries (#18)

* Enable CORS

* Add health check endpoint for load balancers

* Optimize list query

server/src/app.js

@@ -9,9 +9,6 @@ import morgan from 'morgan';
 import route from './route';
 import logger, { stream } from './logger';
 
-
-const ENV = process.env.NODE_ENV;
-
 const sendError = (err, req, res) => {
   logger.error(err.stack);
   const code = err.status || 500;
@@ -52,13 +49,18 @@ export default () => {
   const app = express();
 
   app.use(expressRequestId());
-  if (ENV === 'development') app.use(cors());
+  app.use(cors());
   app.use(compression());
   app.use(bodyParser.json());
   app.use(bodyParser.urlencoded());
   app.use(sseMiddleware);
   app.use(morgan('tiny', { stream }));
 
+  // HealthCheck Endpoint
+  app.get('/', async (_req, res) => {
+    res.send('OK');
+  });
+
   app.use('/api', route);
   app.use('/', express.static('build'));
   app.use('*', (req, res) => {

server/src/db/query.js

@@ -64,11 +64,13 @@ export const listQuery = ({
   return params;
 };
 
-export const listQueryWithCount = (model, ...args) => {
+export const listQueryWithCount = async (model, ...args) => {
   const params = listQuery(...args);
   const { offset } = params;
-  return model.findAndCountAll(params).then(({ count, rows }) => ({
+  const count = await model.max('id');
+  const rows = await model.findAll(params);
+  return {
     data: rows,
     pagination: { count: rows.length, offset, total: count },
-  }));
+  };
 };