Express HTTP Exception Middleware

A simple, TypeScript-friendly middleware for handling HTTP exceptions in Express apps. Provides structured JSON error responses with optional timestamps.

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Installation

npm install http-exceptions-express

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Usage

Basic Setup

import express from "express";
import { httpExceptionMiddleware, NotFoundException } from 'http-exceptions-express';

const app = express();

app.get("/hello", (req, res) => res.json({ msg: "Hello" }));

app.get("/not-found-example", () => { throw new NotFoundException(); });

// Register error middleware last
app.use(httpExceptionMiddleware({ useTimestamp: true }));

app.listen(8000);

Example Error Response

Requesting /not-found-example will return:

{
  "message": "Not Found",
  "timestamp": "2025-12-11T12:34:56.789Z"
}

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API

httpExceptionMiddleware(options?: { useTimestamp?: boolean })

• useTimestamp (boolean, default: false): Include a timestamp in the error response.

Returns an Express error-handling middleware.

NotFoundException

A prebuilt HttpException with status = 404 and message = "Not Found".

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Creating Custom Exceptions

import { HttpException } from '@happer64bit/http-exceptions-express';

class UnauthorizedException extends HttpException {
    constructor(message = "Unauthorized") {
        super(401, message);
    }
}

throw new UnauthorizedException();

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Notes

• Middleware order matters: In Express, error-handling middleware must be registered after all routes to catch errors properly.
• For synchronous routes, this works out-of-the-box.
• For async routes, consider wrapping with a helper like asyncHandler to forward errors.

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License

MIT