n8n-io/n8n · warning · BadRequestError

Invalid nps survey state structure

Error message

Invalid nps survey state structure

What it means

Thrown by PATCH /user-settings/nps-survey when req.body is not a structurally valid NPS survey state. The local getNpsSurveyState() validator only accepts two shapes: a 'responded' state ({responded:true, lastShownAt:number}) or a 'waitingForResponse' state ({waitingForResponse:true, ignoredCount:number, lastShownAt:number}); both require lastShownAt to be a number. Any other object, non-object, missing fields, or wrong types causes this BadRequestError (HTTP 400).

Source

Thrown at packages/cli/src/controllers/user-settings.controller.ts:46

		return {
			waitingForResponse: true,
			ignoredCount: state.ignoredCount,
			lastShownAt: state.lastShownAt,
		};
	}

	return;
}

@RestController('/user-settings')
export class UserSettingsController {
	constructor(private readonly userService: UserService) {}

	@Patch('/nps-survey')
	async updateNpsSurvey(req: NpsSurveyRequest.NpsSurveyUpdate): Promise<void> {
		const state = getNpsSurveyState(req.body);
		if (!state) {
			throw new BadRequestError('Invalid nps survey state structure');
		}

		await this.userService.updateSettings(req.user.id, {
			npsSurvey: state,
		});
	}
}

View on GitHub (pinned to 5ac6606e81)

Solutions

1. Ensure the request body matches one of the two accepted shapes exactly: {responded:true,lastShownAt:<number>} OR {waitingForResponse:true,ignoredCount:<number>,lastShownAt:<number>}.
2. Verify lastShownAt is a numeric Unix-style timestamp (ms), not an ISO string or Date.
3. If adding a new state variant, extend getNpsSurveyState() in user-settings.controller.ts and the NpsSurveyState type in n8n-workflow before relying on it.

Example fix

// before
await patch('/user-settings/nps-survey', { responded: true });
// after
await patch('/user-settings/nps-survey', {
  responded: true,
  lastShownAt: Date.now(),
});

function buildNpsState(input) {
  if (typeof input.lastShownAt !== 'number' || !Number.isFinite(input.lastShownAt)) {
    throw new Error('lastShownAt must be a finite number');
  }
  if (input.responded === true) return { responded: true, lastShownAt: input.lastShownAt };
  if (input.waitingForResponse === true && typeof input.ignoredCount === 'number') {
    return { waitingForResponse: true, ignoredCount: input.ignoredCount, lastShownAt: input.lastShownAt };
  }
  throw new Error('State must be responded:true or waitingForResponse:true+ignoredCount:number');
}
// call before PATCH /user-settings/nps-survey
const body = buildNpsSurveyState(rawState);

function isNpsSurveyState(s: unknown): s is { lastShownAt: number } & (
  | { responded: true }
  | { waitingForResponse: true; ignoredCount: number }
) {
  if (typeof s !== 'object' || s === null) return false;
  const o = s as Record<string, unknown>;
  if (typeof o.lastShownAt !== 'number') return false;
  if (o.responded === true) return true;
  return o.waitingForResponse === true && typeof o.ignoredCount === 'number';
}

When it happens

Trigger: Calling PATCH /user-settings/nps-survey with a body that is not an object, lacks lastShownAt, has lastShownAt as a non-number, or declares neither responded:true nor the waitingForResponse+ignoredCount combo (e.g. {responded:true} alone, or {lastShownAt:'2024-01-01'}).

Common situations: Frontend NPS survey component sending a partial state object during an A/B test variant, a stale frontend shipping an outdated state schema after a backend bump, hand-crafted curl/automation with malformed JSON, or a serializer stripping numeric fields to strings.

Related errors

• error.message
• Missing binary data ID
• Malformed binary data ID
• Invalid binary data mode
• Token is required

AI-assisted analysis of n8n-io/n8n@5ac6606e81 (2026-08-12). Data as JSON: /api/errors/9efb32ea23314fdd. Report an issue: GitHub.