add database error handling

src/controllers/hello.controller.ts

@@ -11,7 +11,7 @@ const controller: RequestHandler = async (req, res) => {
 		req.body,
 		z.object({
 			customPrefix: z.enum(["Hey", "Hi"]).optional(),
-			name: z.string(),
+			name: z.string().min(1),
 		})
 	);
 

src/errors/database.handler.ts

@@ -0,0 +1,21 @@
+import { ErrorRequestHandler } from "express";
+import { DrizzleError } from "drizzle-orm";
+import { JSendException } from "@/utils/exception";
+
+/**
+ * Handles all Drizzle errors and converts them to JSend exceptions
+ */
+const handler: ErrorRequestHandler = (err, req, res, next) => {
+	if (err instanceof DrizzleError) {
+		return next(
+			new JSendException(500, {
+				status: "error",
+				message: err.message,
+			})
+		);
+	}
+
+	next(err);
+};
+
+export default handler;

src/errors/global.handler.ts

@@ -0,0 +1,32 @@
+import { JSendException } from "@/utils/exception";
+import { JSend } from "@/utils/jsend";
+import type { ErrorRequestHandler } from "express";
+
+/**
+ * Global error handler for the application. This function should be the last middleware in the chain
+ * to catch any errors that were not handled by the other middlewares
+ *
+ * You can use JSendException to throw errors from your controllers and services
+ */
+const globalErrorHandler: ErrorRequestHandler = (err, req, res, next) => {
+	if (err instanceof JSendException) {
+		return res.status(err.status).json(err.response);
+	}
+
+	console.error(err);
+
+	/**
+	 * Any errors that were not manually throw with JSendException will return a 500 status code
+	 *
+	 * Ideally, the API should not reach this point. Instead, all errors should be handled by
+	 * throwing JSendException with the appropriate status code and response
+	 *
+	 * A good pattern for that is creating a chain of error handlers to handle different types of
+	 * errors that are not manually throwed (database errors, ...) and convert them to
+	 * JSendException before reaching the global error handler. This is done, for example, in the
+	 * `src/errors/database.handler.ts` file
+	 */
+	res.status(500).json(JSend.error("Internal Server Error"));
+};
+
+export default globalErrorHandler;

src/main.ts

@@ -4,7 +4,8 @@ import cors from "cors";
 import bodyParser from "body-parser";
 import routes from "@/routes";
 import dotenv from "@/lib/dotenv";
-import errorHandler from "@/lib/error-handler";
+import databaseErrorHandler from "@/errors/database.handler";
+import globalErrorHandler from "@/errors/global.handler";
 
 const app = express();
 
@@ -25,14 +26,16 @@ app.use(
 		 *
 		 * {@link https://cheatsheetseries.owasp.org/cheatsheets/Cross-Site_Request_Forgery_Prevention_Cheat_Sheet.html#custom-headers-and-cors}
 		 */
-		origin: [new RegExp("http://localhost:\\d*"), "https://example.com"],
+		origin: [new RegExp("http://localhost:\\d+"), "https://example.com"],
 		credentials: true,
 	})
 );
 
 app.use("/api", routes);
 
-app.use(errorHandler);
+// Error handlers. The global error handler must be the last middleware in the chain
+app.use(databaseErrorHandler);
+app.use(globalErrorHandler);
 
 app.listen(dotenv.SERVER_PORT, () => {
 	console.log(`🚀 Server is running on port ${dotenv.SERVER_PORT}`);

src/services/hello.service.ts

@@ -1,3 +1,5 @@
+// This is only an example file. You can safely delete it
+
 export function getHelloMessage(name: string, prefix: string = "Hello") {
 	return `${prefix}, ${name}!`;
 }

tsconfig.json

@@ -1,4 +1,5 @@
 {
+	"exclude": ["node_modules"],
 	"compilerOptions": {
 		"baseUrl": ".",
 		"paths": {