Overriding Middleware Failure Responses

ZinTrust middleware returns a structured failure payload by default and keeps the middleware-provided status code unless a custom responder changes it:

{
  "error": {
    "code": "SOME_ERROR_CODE",
    "message": "Human readable message"
  }
}

For auth and jwt middleware, the default unauthorized status remains 401.

The supported extension point is the responder contract exposed through middleware configuration. A responder can:

1. keep the default status and only reshape the body
2. replace both the public body shape and the HTTP status when a project needs a different contract

Example:

// app/Middleware/AuthFailureResponder.ts
import type { MiddlewareFailureResponder } from '@zintrust/core';

export const authFailureResponder: MiddlewareFailureResponder = async (_req, res, context) => {
  res.setStatus(403).json({
    message: 'Unauthorized',
    status: 403,
    ty: 'OT',
    reason: context.reason,
  });
};

Then wire it through project middleware config:

// config/middleware.ts
import { authFailureResponder } from '@app/Middleware/AuthFailureResponder';

export default {
  responders: {
    auth: authFailureResponder,
    jwt: authFailureResponder,
  },
};

Notes:

1. the root package exports defaultMiddlewareFailureResponder, respondWithMiddlewareFailure, and the responder types
2. the root package does not currently export createDefaultMiddlewareFailureBody
3. there is no public MiddlewareFailureResponder.create(...) helper on the root package
4. prefer responders for app-level customization instead of patching installed core middleware files

If you need to keep the default 401, simply write your responder with context.statusCode instead of replacing it.