Connectum API Reference / @connectum/interceptors / errorHandler / createErrorHandlerInterceptor

Function: createErrorHandlerInterceptor()

createErrorHandlerInterceptor(options?): Interceptor

Defined in: errorHandler.ts:74

Create error handler interceptor

Catches rejections from awaiting next(req) and transforms them into ConnectError instances with proper error codes. Recognizes SanitizableError for safe client-facing messages while preserving server details for logging.

What a client receives for each kind of thrown value:

• ConnectError: passes through unchanged, text and details included. Its author chose to send them.
• SanitizableError: its clientMessage and code only; serverDetails stay on the server.
• Anything else (Error, a thrown string, an object with a numeric code): the code is the numeric code when there is one and Internal otherwise. The text of the failure is NOT sent: Internal carries the fixed text "internal error", any other code carries an empty text. A message such as a connection string or a query would otherwise leak to every caller (CWE-209). Set exposeErrorMessages: true to send the original text.

The original failure always stays on the server: as cause of the thrown ConnectError (no transport serializes cause), in onError as info.error with its original text, and in the console log.

Place this interceptor first to normalize rejections from downstream interceptors. It does not wrap response-stream iteration after next(req) returns, or errors from request gates that run before the interceptor chain.

Parameters

options?

ErrorHandlerOptions = {}

Error handler options

Returns

Interceptor

ConnectRPC interceptor

Example

Server-side usage with createServer

import { createServer } from '@connectum/core';
import { createErrorHandlerInterceptor } from '@connectum/interceptors';
import { myRoutes } from './routes.js';

const server = createServer({
  services: [myRoutes],
  interceptors: [
    createErrorHandlerInterceptor({
      onError: ({ error, code, serverDetails, stack }) => {
        logger.error('RPC error', { error: error.message, code, serverDetails, stack });
      },
    }),
  ],
});

await server.start();