feat: handle server errors in api (#66)

## Description

- Handle server/3rd party modules errors with 500 status code on API
- Don't cache 500 errors

apps/api/src/app.ts

@@ -5,6 +5,7 @@ import { ILogger } from "@zkchainhub/shared";
 
 import { listRoutes, setupOpenApiConfiguration as setupOpenApi } from "./api-docs/index.js";
 import { ConfigType } from "./common/config/index.js";
+import { generalErrorHandler } from "./common/middleware/generalError.middleware.js";
 import { requestLogger } from "./common/middleware/requestLogger.middleware.js";
 import { zodErrorHandler } from "./common/middleware/zodError.middleware.js";
 import { BaseRouter } from "./common/routes/baseRouter.js";
@@ -64,5 +65,6 @@ export class App {
 
     private initializeErrorHandling(): void {
         this.app.use(zodErrorHandler);
+        this.app.use(generalErrorHandler);
     }
 }

apps/api/src/common/middleware/cache.middleware.ts

@@ -22,10 +22,11 @@ export function cacheMiddleware(args: { ttl: number } = { ttl: DEFAULT_TTL }) {
             // Store the original send and json functions
             const originalJson = res.json.bind(res);
             // Override the json function
-
             res.json = (body): Response => {
-                // Cache the response body
-                cache.set(key, body, args.ttl);
+                if (!("errors" in body)) {
+                    // Cache the response body if it is not an error response
+                    cache.set(key, body, args.ttl);
+                }
                 // Call the original json function with the response body
                 return originalJson(body);
             };

apps/api/src/common/middleware/generalError.middleware.ts

@@ -0,0 +1,14 @@
+import { isNativeError } from "util/types";
+import { NextFunction, Request, Response } from "express";
+
+export const generalErrorHandler = (
+    err: unknown,
+    req: Request,
+    res: Response,
+    _next: NextFunction,
+) => {
+    return res.status(500).json({
+        message: "Internal server error",
+        errors: isNativeError(err) ? err.message : err,
+    });
+};

apps/api/src/common/middleware/index.ts

@@ -1,2 +1,3 @@
 export * from "./zodError.middleware.js";
 export * from "./requestLogger.middleware.js";
+export * from "./generalError.middleware.js";