@janindu-pathirana/http-errors

A reusable Node.js and TypeScript library for structured HTTP error classes and unified error handling.

Installation

npm install @janindu-pathirana/http-errors

Features

• Custom HTTP error classes for common HTTP status codes
• Centralized HttpError.handleError helper for safer error handling
• ESM and CommonJS support via bundled dist output
• Automatically typed for TypeScript projects

Usage

import {
  HttpError,
  BadRequestError,
  InternalServerError,
} from "@janindu-pathirana/http-errors";

try {
  throw new BadRequestError("bad");
} catch (error) {
  HttpError.handleError(error, new InternalServerError("something went wrong"));
}

Available Error Classes

• BadRequestError — 400 Bad Request
• UnauthorizedError — 401 Unauthorized
• ForbiddenError — 403 Forbidden
• NotFoundError — 404 Not Found
• InternalServerError — 500 Internal Server Error
• DatabaseError — custom database error type
• HttpError — base class for creating custom HTTP errors

Express / NestJS Example

import express from "express";
import {
  HttpError,
  NotFoundError,
  InternalServerError,
} from "@janindu-pathirana/http-errors";

const app = express();

app.get("/resource", (req, res) => {
  throw new NotFoundError("Resource not found");
});

app.use(
  (
    error: unknown,
    req: express.Request,
    res: express.Response,
    next: express.NextFunction,
  ) => {
    HttpError.handleError(
      error,
      new InternalServerError("Unexpected server error"),
    );
  },
);

app.listen(3000, () => {
  console.log("Server running on http://localhost:3000");
});

The same pattern works in NestJS controllers and exception filters, since the package exports standard error classes.

API Reference

new HttpError(message?: string, statusCode?: number)

• message — error message string (default: "Error")
• statusCode — HTTP status code (default: 500)

new BadRequestError(message?: string)

• message — error message string (default: "Bad Request")

new UnauthorizedError(message?: string)

• message — error message string (default: "Unauthorized")

new ForbiddenError(message?: string)

• message — error message string (default: "Forbidden")

new NotFoundError(message?: string)

• message — error message string (default: "Not Found")

new InternalServerError(message?: string)

• message — error message string (default: "Internal Server Error")

new DatabaseError(message?: string)

• message — error message string

HttpError.handleError(error: unknown, fallback: HttpError)

• error — the caught exception
• fallback — fallback HttpError instance to use when the caught value is not an HttpError

Error Handling Example

import {
  HttpError,
  BadRequestError,
  InternalServerError,
} from "@janindu-pathirana/http-errors";

try {
  throw new BadRequestError("Invalid input provided");
} catch (error) {
  HttpError.handleError(error, new InternalServerError("something went wrong"));
}

TypeScript Support

This package includes built-in TypeScript type definitions. Import the error classes directly and benefit from typed constructor signatures and HttpError helpers.

Publishing / Version

The package is published as @janindu-pathirana/http-errors with version 1.0.0 in package.json.

License

MIT