Nest-exception NPM

nest-exception

This package is based on Original NestJs Http exceptions. nest-exception brings the simplicity and structured approach of NestJS error handling to any Node.js application. This for non NestJs projects.

License

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

Installation

To install the package, run:

npm install nest-exception

or with yarn:

yarn add nest-exception

Why `nest-exception`?

NestJS provides an excellent mechanism for handling exceptions, but it is tightly coupled with the Nest framework. nest-exception bridges the gap by offering a same structured error-handling experience to projects outside of NestJS. It allows you to:

Define custom exceptions with meaningful metadata.
Maintain consistency in error responses.
Improve debugging with detailed error information.

Features

Structured Errors: Create exceptions with a clear structure and metadata.
Customizable: Easily define custom exceptions tailored to your application needs.
Framework Agnostic: Designed for use in any Node.js project.
Inspired by NestJS: Brings the familiarity and power of NestJS exceptions to non-NestJS projects.

Usage

Basic Example

const { HttpException, NotFoundException } = require('nest-exception');

// Throwing a general exception
throw new HttpException('An error occurred', 500);

// Throwing a specific exception
throw new NotFoundException('Resource not found');

Custom Exceptions

You can extend the base HttpException class to define custom exceptions:

const { HttpException } = require('nest-exception');

class CustomException extends HttpException {
  constructor(message, statusCode, customData) {
    super(message, statusCode);
    this.customData = customData;
  }
}

throw new CustomException('A custom error occurred', 400, { field: 'value' });

Handling Exceptions

Use a centralized error-handling middleware to catch and respond to exceptions in your application:

const express = require('express');
const { HttpException } = require('nest-exception');

const app = express();

// Middleware to handle exceptions
app.use((err, req, res, next) => {
  if (err instanceof HttpException) {
    return res.status(err.status).json({
      message: err.message,
      statusCode: err.status,
      ...err,
    });
  }

  // Default to 500 for unexpected errors
  res.status(500).json({
    message: 'Internal Server Error',
  });
});

app.listen(3000, () => console.log('Server is running on port 3000'));