Amazon Cognito
Developer Guide

Pre-Authentication Lambda Parameters

Amazon Cognito invokes this trigger when a user attempts to authenticate (sign in), allowing you to perform custom validation to accept or deny the authentication request.

The request includes validation data from the client.

"request": { "userAttributes": { "string": "string", .... }, "validationData": {<validation data as key-value (String, String) pairs, from the client>} }

One or more name-value pairs representing user attributes.


One or more key-value pairs containing the validation data in the user's sign-in request.

No return information is expected in the response.

"response": { }