fix middleware stuff

backend/src/index.js

@@ -47,12 +47,10 @@ 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) => {
-  res.status(404).send("Not Found");
-})
-
-// has to be last
-app.use((_req, res, _next) => {
+app.use((_req, res, next) => {
+  if (res.error == null) {
+    return res.status(404).send("Not Found");
+  } else {
     const err = res.error;
     if (err instanceof ApiError) {
       return res.status(err.status).json({ status: "error", error: err.message });
@@ -60,6 +58,7 @@ app.use((_req, res, _next) => {
 
     console.error(err);
     res.status(500).json({ status: "error", error: "Internal server error" });
+  }
 })
 
 const server = https.createServer({