问题
I've configured a User Pool in Amazon Cognito to be able to sign-in/sign-up users and I've setup facebook as identity provider.
On my hosted ui (https://xxx.auth.us-east-1.amazoncognito.com/login?client_id=2yyy&redirect_uri=zzzz.com.br&response_type=code), I could successfully click on "continue with facebook" but after I got redirect to my return_uri the following error as query parameter was shown:
https://zzzz.com.br/?error_description=username+attribute+mapping+required&error=invalid_request#=
Under the "Attribute mapping" configuration I already have facebook attribute "id" mapped to User pool attribute "Username"... After some hours struggling with this I decided to ask you guys for help!
Thanks in advance.
来源：https://stackoverflow.com/questions/50430759/cognito-error-description-username-attribute-mapping