How do you re-throw an exception from within a filter to let a higher-scoped filter handle it in NestJS?

Q: How do you re-throw an exception from within a filter to let a higher-scoped filter handle it in NestJS?

// Method-level audit filter — side effect only, delegates response to global @Catch(HttpException) export class AuditFilter implements ExceptionFilter { constructor(private readonly audit: AuditService) {} catch(exception: HttpException, host: ArgumentsHost): void { const req = host.switchToHttp().getRequest(); // Only record 401 / 403 for security auditing if ([401, 403].includes(exception.getStatus())) { // Fire-and-forget — do not await this.audit .record({ url: req.url, status: exception.getStatus(), userId: req.user?.id }) .catch(err => console.error('Audit failed', err)); } // Re-throw — let the global AllExceptionsFilter send the response throw exception; } } // Global filter — owns all HTTP response sending @Catch() export class AllExceptionsFilter implements ExceptionFilter { catch(exception: unknown, host: ArgumentsHost): void { const status = exception instanceof HttpException ? exception.getStatus() : 500; host.switchToHttp().getResponse() .status(status) .json({ statusCode: status }); } } Single responsibility — the audit filter only audits; the global filter only sends responses. No duplication of response logic across multiple filters. Re-thrown exceptions follow the same method -> controller -> global resolution path. Narrow filters can choose to handle some exceptions and re-throw others based on the status code. This pattern is composable — add or remove audit behavior without touching the response filter.

Difficulty: 5/10

Exception Filters, Error Propagation, NestJS Architecture

A filter can perform its side effect (auditing, metrics) and then re-throw the exception using throw exception. Because filter resolution goes method → controller → global, the re-thrown exception propagates to the next wider-scoped filter that matches it. This pattern enables composable single-responsibility filters.

Narrow filter re-throwing to global filter

Re-throw pattern design benefits:

1
Single responsibility — the audit filter only audits; the global filter only sends responses.
2

How do you re-throw an exception from within a filter to let a higher-scoped filter handle it in NestJS?

Difficulty: 5/10

Exception Filters, Error Propagation, NestJS Architecture

A filter can perform its side effect (auditing, metrics) and then re-throw the exception using throw exception. Because filter resolution goes method → controller → global, the re-thrown exception propagates to the next wider-scoped filter that matches it. This pattern enables composable single-responsibility filters.

Narrow filter re-throwing to global filter

Re-throw pattern design benefits:

1
Single responsibility — the audit filter only audits; the global filter only sends responses.
2

How do you re-throw an exception from within a filter to let a higher-scoped filter handle it in NestJS?

How do you re-throw an exception from within a filter to let a higher-scoped filter handle it in NestJS?

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