fix middleware again

backend/src/api.js

@@ -11,10 +11,7 @@ export class ApiError extends Error {
 }
 
 const router = Router();
-const asyncHandler = fn => (req, res, next) => Promise.resolve(fn(req, res, next)).catch(err => {
-    res.error = err;
-    next();
-});
+const asyncHandler = fn => (req, res, next) => Promise.resolve(fn(req, res, next)).catch(next);
 
 const userSchema = Joi.object({
     username: Joi.string().min(3).max(32).required()

backend/src/index.js

@@ -47,19 +47,14 @@ app.use(express.static(path.join(__dirname, "public"), {
 app.use("/api/docs", swaggerUi.serve, swaggerUi.setup(specs));
 app.use("/api", apiRouter);
 
-app.use((_req, res, next) => {
-  if (res.error == null) {
-    return res.status(404).send("Not Found");
-  } else {
-    const err = res.error;
+app.use((err, req, res, next) => {
   if (err instanceof ApiError) {
     return res.status(err.status).json({ status: "error", error: err.message });
   }
 
   console.error(err);
   res.status(500).json({ status: "error", error: "Internal server error" });
-  }
-})
+});
 
 const server = https.createServer({
   key: fs.readFileSync('server.key'),