What does NestJS's built-in global exception layer do when no custom filter is registered?

Q: What does NestJS's built-in global exception layer do when no custom filter is registered?

// HttpException — built-in layer returns its body and status throw new NotFoundException('User not found'); // Response: { statusCode: 404, message: 'User not found', error: 'Not Found' } // Non-HttpException — built-in layer hides all details throw new Error('DB connection lost'); // Response: { statusCode: 500, message: 'Internal server error' } // HttpException with object body — body is returned as-is throw new BadRequestException({ message: 'Invalid email', field: 'email' }); // Response: { message: 'Invalid email', field: 'email' } Always active — runs even without any custom filter configuration. HttpException — serializes the response body from getResponse() with the correct status code. Non-HttpException — returns a generic 500 response, never exposing internal error details. Custom filters extend or override this behavior but never fully remove it. The built-in layer acts as the final safety net behind all custom filters.

Difficulty: 3/10

exception handling, global filters, NestJS core

NestJS ships a built-in global exception filter that catches every unhandled exception automatically. For HttpException it serializes the response body and sends the correct HTTP status. For any other exception type it returns a generic 500 Internal Server Error response, hiding implementation details from the client.

Built-in exception layer behavior

Built-in exception layer key facts:

1
Always active — runs even without any custom filter configuration.
2
HttpException — serializes the response body from getResponse() with the correct status code.
3

What does NestJS's built-in global exception layer do when no custom filter is registered?

Difficulty: 3/10

exception handling, global filters, NestJS core

NestJS ships a built-in global exception filter that catches every unhandled exception automatically. For HttpException it serializes the response body and sends the correct HTTP status. For any other exception type it returns a generic 500 Internal Server Error response, hiding implementation details from the client.

Built-in exception layer behavior

Built-in exception layer key facts:

1
Always active — runs even without any custom filter configuration.
2
HttpException — serializes the response body from getResponse() with the correct status code.
3

What does NestJS's built-in global exception layer do when no custom filter is registered?

What does NestJS's built-in global exception layer do when no custom filter is registered?

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