How do you write a production-ready global all-exceptions filter that handles HttpException and unexpected errors differently?

Q: How do you write a production-ready global all-exceptions filter that handles HttpException and unexpected errors differently?

@Catch() export class AllExceptionsFilter implements ExceptionFilter { constructor(private readonly logger: LoggerService) {} catch(exception: unknown, host: ArgumentsHost): void { const ctx = host.switchToHttp(); const res = ctx.getResponse (); const req = ctx.getRequest (); let status = HttpStatus.INTERNAL_SERVER_ERROR; let message: string | string[] = 'Internal server error'; if (exception instanceof HttpException) { // Expected client error — expose details safely status = exception.getStatus(); const body = exception.getResponse(); message = typeof body === 'string' ? body : (body as any).message ?? 'An error occurred'; } else if (exception instanceof Error) { // Unexpected — log full details, expose nothing this.logger.error(exception.message, exception.stack); } else { this.logger.error('Unknown thrown value', String(exception)); } res.status(status).json({ statusCode: status, message, path: req.url, timestamp: new Date().toISOString(), }); } } Always log the full error including stack trace for unexpected errors. Never expose internal error details, stack traces, or DB errors to the client. HTTP exceptions are expected client errors — surface their message and status code. Unknown errors should always return 500 with a generic message. Include the request path and timestamp in error responses for client-side debugging.

Difficulty: 7/10

Exception handling, NestJS filters, Error logging

Use @Catch() with no argument to catch everything. Branch on instanceof HttpException — known HTTP exceptions expose their status and message to the client. Unknown errors are logged in full server-side but return a generic 500 to the client. This two-branch pattern is the production standard.

Production global all-exceptions filter

Production error handling best practices:

1
Always log the full error including stack trace for unexpected errors.
2

How do you write a production-ready global all-exceptions filter that handles HttpException and unexpected errors differently?

Difficulty: 7/10

Exception handling, NestJS filters, Error logging

Use @Catch() with no argument to catch everything. Branch on instanceof HttpException — known HTTP exceptions expose their status and message to the client. Unknown errors are logged in full server-side but return a generic 500 to the client. This two-branch pattern is the production standard.

Production global all-exceptions filter

Production error handling best practices:

1
Always log the full error including stack trace for unexpected errors.
2

How do you write a production-ready global all-exceptions filter that handles HttpException and unexpected errors differently?

Use @Catch() with no argument to catch everything. Branch on instanceof HttpException — known HTTP exceptions expose their status and message to the client. Unknown errors are logged in full server-side but return a generic 500 to the client. This two-branch pattern is the production standard.

How do you write a production-ready global all-exceptions filter that handles HttpException and unexpected errors differently?

Use @Catch() with no argument to catch everything. Branch on instanceof HttpException — known HTTP exceptions expose their status and message to the client. Unknown errors are logged in full server-side but return a generic 500 to the client. This two-branch pattern is the production standard.

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