What is the cause option on HttpException and how should you use it for error tracing?

Q: What is the cause option on HttpException and how should you use it for error tracing?

// Attach the original error as cause when wrapping infrastructure exceptions try { await this.db.query('SELECT ...'); } catch (dbError) { throw new InternalServerErrorException( 'Failed to load user profile', { cause: dbError }, // dbError.message never reaches the client ); } // In your global filter — read and log cause, send safe message catch(exception: HttpException, host: ArgumentsHost) { const cause = exception.cause; // the original Error object if (cause instanceof Error) { this.logger.error(exception.message, cause.stack); // full trace in logs } // Only the public message goes to the client res.status(exception.getStatus()).json({ statusCode: exception.getStatus(), message: exception.message, }); } cause is purely for server-side observability — it is not included in the HTTP response body by default. Attach the original database, SDK, or third-party error as cause when wrapping it in an HttpException. Read exception.cause inside your global filter to log the full original stack trace. This pattern separates what you log (everything) from what you expose to clients (safe messages only). exception.cause is available as a public property on any HttpException instance.

Difficulty: 5/10

HttpException, cause option, error tracing

The options.cause property attaches an inner Error to the HttpException for server-side observability. It is never serialized into the HTTP response body. In your global filter you can read exception.cause and log the full stack trace while sending only a safe public message to the client.

Using cause for safe error tracing

How to use cause correctly:

1
cause is purely for server-side observability — it is not included in the HTTP response body by default.
2
Attach the original database, SDK, or third-party error as cause when wrapping it in an HttpException.

What is the cause option on HttpException and how should you use it for error tracing?

Difficulty: 5/10

HttpException, cause option, error tracing

The options.cause property attaches an inner Error to the HttpException for server-side observability. It is never serialized into the HTTP response body. In your global filter you can read exception.cause and log the full stack trace while sending only a safe public message to the client.

Using cause for safe error tracing

How to use cause correctly:

1
cause is purely for server-side observability — it is not included in the HTTP response body by default.
2
Attach the original database, SDK, or third-party error as cause when wrapping it in an HttpException.

What is the cause option on HttpException and how should you use it for error tracing?

The options.cause property attaches an inner Error to the HttpException for server-side observability. It is never serialized into the HTTP response body. In your global filter you can read exception.cause and log the full stack trace while sending only a safe public message to the client.

What is the cause option on HttpException and how should you use it for error tracing?

The options.cause property attaches an inner Error to the HttpException for server-side observability. It is never serialized into the HTTP response body. In your global filter you can read exception.cause and log the full stack trace while sending only a safe public message to the client.

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