first commit

server/middleware/errorHandler.js

@@ -0,0 +1,58 @@
+const logger = require('../utils/logger');
+
+const errorHandler = (err, req, res, next) => {
+  let error = { ...err };
+  error.message = err.message;
+
+  // Log error
+  logger.error(err);
+
+  // Mongoose bad ObjectId
+  if (err.name === 'CastError') {
+    const message = 'Resource not found';
+    error = { message, statusCode: 404 };
+  }
+
+  // Mongoose duplicate key
+  if (err.code === 11000) {
+    const message = 'Duplicate field value entered';
+    error = { message, statusCode: 400 };
+  }
+
+  // Mongoose validation error
+  if (err.name === 'ValidationError') {
+    const message = Object.values(err.errors).map(val => val.message).join(', ');
+    error = { message, statusCode: 400 };
+  }
+
+  // Sequelize validation error
+  if (err.name === 'SequelizeValidationError') {
+    const message = err.errors.map(e => e.message).join(', ');
+    error = { message, statusCode: 400 };
+  }
+
+  // Sequelize unique constraint error
+  if (err.name === 'SequelizeUniqueConstraintError') {
+    const message = 'Duplicate field value entered';
+    error = { message, statusCode: 400 };
+  }
+
+  // JWT errors
+  if (err.name === 'JsonWebTokenError') {
+    const message = 'Invalid token';
+    error = { message, statusCode: 401 };
+  }
+
+  if (err.name === 'TokenExpiredError') {
+    const message = 'Token expired';
+    error = { message, statusCode: 401 };
+  }
+
+  res.status(error.statusCode || 500).json({
+    success: false,
+    error: error.message || 'Server Error',
+    ...(process.env.NODE_ENV === 'development' && { stack: err.stack })
+  });
+};
+
+module.exports = errorHandler;