error-handler-package v1.0.1

Error Handler Package

A robust error-handling package for Node.js applications using Express. This package provides custom error classes and middleware to handle various types of errors, such as validation errors, JWT errors, and more.

Installation

To install this package, use npm:

npm install error-handler-package

Usage

Import the Package

In your Express application, import the necessary components from the package:

import express from "express";
import { AppError, globalErrorHandler } from "error-handler-package";

Setup Middleware

Use the error-handling middleware in your Express app:

const app = express();

// Middleware for parsing JSON
app.use(express.json());

// Global error handling middleware
app.use(globalErrorHandler);

Using in Controllers

You can use the AppError class in your controllers to throw errors:

// userController.js
export const getUser = (req, res, next) => {
  const user = findUserById(req.params.id);
  if (!user) {
    return next(new AppError("User not found", 404));
  }
  res.status(200).json({
    status: "success",
    data: { user },
  });
};

export const updateUser = (req, res, next) => {
  try {
    const updatedUser = updateUserById(req.params.id, req.body);
    if (!updatedUser) {
      return next(new AppError("Failed to update user", 400));
    }
    res.status(200).json({
      status: "success",
      data: { user: updatedUser },
    });
  } catch (error) {
    next(new AppError("An error occurred while updating user", 500));
  }
};

Handle Undefined Routes

You can handle undefined routes by using the AppError class:

app.all("*", (req, res, next) => {
  next(new AppError(`Can't find ${req.originalUrl} on this server!`, 404));
});

Run the Server

Start your server as usual:

const port = process.env.PORT || 3000;
app.listen(port, () => {
  console.log(`Server running on port ${port}`);
});

Features

• Custom Error Class: AppError allows you to create operational errors with a status code and message.
• Error Handling Middleware: Centralized error handling for different environments (development and production).
• Predefined Error Handlers: Includes handlers for common errors like CastError, ValidationError, and JWT errors.

License

This project is licensed under the MIT License - see the LICENSE file for details.