initial commit

controllers/errorController.js

@@ -0,0 +1,63 @@
+/* eslint-disable no-param-reassign */
+
+////////////////////////////////////////////////////////
+//                      IMPORTS
+////////////////////////////////////////////////////////
+import log from '../utils/log.js';
+
+////////////////////////////////////////////////////////
+//                    FUNCTIONS
+////////////////////////////////////////////////////////
+/**
+ * @description function to send error responses to the client
+ * @param {{}} err error object
+ * @param {{}} req request object provided by express
+ * @param {{}} res response object provided by express
+ * @param {boolean} devMode if set to true, will send full stack trace to the client
+ */
+const sendErrorResponse = (err, req, res, devMode = false) => {
+  // 1. FOR API
+  if (req.originalUrl.startsWith('/api/'))
+    res.status(err.statusCode).json({
+      status: err.status,
+      message: err.message,
+      // only if devMode is true, will this stack trace get sent. using es6 spreading and short circuiting
+      ...(devMode && { stack: err.stack }),
+    });
+  // 2. FOR WEBPAGES
+  else
+    res.status(err.statusCode).render('error', {
+      title: 'Error',
+      statusCode: err.statusCode,
+      message: err.message,
+      ...(devMode && { stack: err.stack }),
+    });
+};
+
+/**
+ * @description function to handle all errors occuring in the app
+ * @param {{}} err object containing full error
+ * @param {{}} req request object in express
+ * @param {{}} res response object in express
+ * @param {function} next function to call next middleware in express
+ */
+
+const globalErrorHandler = (err, req, res, next) => {
+  // since not all errors will be an instance of AppError class(as not errors will be manually thrown by us), we have to set sensible defaults before dealing with those errors
+  err.statusCode = err.statusCode || 500;
+  err.status = err.status || 'error';
+  log(err, 'error');
+
+  if (process.env.NODE_ENV === 'development')
+    sendErrorResponse(err, req, res, true);
+  else {
+    // if error is not operational, sending a generic error message and not revealing full details in production mode
+    if (err.name !== 'OperationalError') err.message = 'something went wrong!';
+    sendErrorResponse(err, req, res);
+  }
+};
+
+////////////////////////////////////////////////////////
+//                     EXPORTS
+////////////////////////////////////////////////////////
+export default globalErrorHandler;