move to src

server/src/middleware/responseHandler.js

@@ -0,0 +1,66 @@
+/**
+ * Middleware that adds standardized response methods to the Express response object.
+ * This allows for consistent API responses throughout the application.
+ *
+ * @param {import('express').Request} req - Express request object
+ * @param {import('express').Response} res - Express response object
+ * @param {import('express').NextFunction} next - Express next middleware function
+ */
+const responseHandler = (req, res, next) => {
+	/**
+	 * Sends a standardized success response
+	 *
+	 * @param {Object} options - Success response options
+	 * @param {number} [options.status=200] - HTTP status code
+	 * @param {string} [options.msg="OK"] - Success message
+	 * @param {*} [options.data=null] - Response data payload
+	 * @returns {Object} Express response object
+	 */
+	res.success = ({ status = 200, msg = "OK", data = null, headers = {} }) => {
+		// Set custom headers if provided
+		Object.entries(headers).forEach(([key, value]) => {
+			res.set(key, value);
+		});
+
+		return res.status(status).json({
+			success: true,
+			msg: msg,
+			data: data,
+		});
+	};
+
+	/**
+	 * Sends a standardized error response
+	 *
+	 * @param {Object} options - Error response options
+	 * @param {number} [options.status=500] - HTTP status code
+	 * @param {string} [options.msg="Internal server error"] - Error message
+	 * @param {*} [options.data=null] - Additional error data (if any)
+	 * @returns {Object} Express response object
+	 */
+	res.error = ({ status = 500, msg = "Internal server error", data = null }) => {
+		return res.status(status).json({
+			success: false,
+			msg,
+			data,
+		});
+	};
+
+	/**
+	 * Sends a raw file response (for CSV, PDF, etc.)
+	 * @param {Object} options
+	 * @param {Buffer|string} options.data - The file content
+	 * @param {Object} options.headers - Headers to set (e.g. Content-Type, Content-Disposition)
+	 * @param {number} [options.status=200] - HTTP status code
+	 */
+	res.file = ({ data, headers = {}, status = 200 }) => {
+		Object.entries(headers).forEach(([key, value]) => {
+			res.setHeader(key, value);
+		});
+		return res.status(status).send(data);
+	};
+
+	next();
+};
+
+export { responseHandler };