What is HttpException in NestJS and what two arguments does its constructor take?

Q: What is HttpException in NestJS and what two arguments does its constructor take?

// String response — NestJS wraps it as { message, statusCode } throw new HttpException('Forbidden', HttpStatus.FORBIDDEN); // Object response — fully custom body shape throw new HttpException( { statusCode: 403, message: 'You lack permission', error: 'Forbidden' }, HttpStatus.FORBIDDEN, ); // options.cause — inner error for logging, never sent to client throw new HttpException( 'Database lookup failed', HttpStatus.INTERNAL_SERVER_ERROR, { cause: new Error('Connection timeout') }, ); response — a string or plain object. Strings are automatically wrapped as { message, statusCode }. status — the HTTP status code. Use the HttpStatus enum for readability. options.cause — an inner error attached for debugging; never serialized into the HTTP response body. All NestJS built-in exceptions (NotFoundException, BadRequestException, etc.) extend HttpException. Use HttpStatus enum constants instead of raw numbers for self-documenting code.

Difficulty: 4/10

error handling, NestJS exceptions, HTTP status codes

HttpException is the base class for all HTTP exceptions in NestJS. Its constructor takes a response argument (string or object that becomes the response body), a status argument (the HTTP status code), and an optional options object. The options.cause property attaches an inner error for server-side logging without exposing it to the client.

HttpException constructor usage

Constructor arguments explained:

1
response — a string or plain object. Strings are automatically wrapped as { message, statusCode }.
2
status — the HTTP status code. Use the HttpStatus enum for readability.
3
options.cause — an inner error attached for debugging; never serialized into the HTTP response body.
4
All NestJS built-in exceptions (NotFoundException, BadRequestException, etc.) extend HttpException.
5
Use HttpStatus enum constants instead of raw numbers for self-documenting code.

Scenario Questions

0-2 years experience

2-5 years experience

1During a recent feature you threw new HttpException('Invalid data', 400) but the client got a 500. How would you investigate and fix the issue?

Follow-up Questions