I want to create a simple flutter mobile+web application.
Login and registration using Cognito is pretty straight-forward in flutter, however integrating it with IoT Core mqtt broker is not as easy.
I want to have the users from My User Pool have an access to publish and subscribe to topic1/*, via being authenticated only through Cognito - without any additional certs.
From amazon documentation I found that I would need Custom authentication for MQTT over WebSocket (Web), and for MQTT (Mobile) too, as I don't want each mobile end-user to have a separate certificate for their usage on the app.
What should be the AWS configuration of identity pools, policies, iot core etc. (practically everything) to have such authentication and then authorization via simple cognito login to work on IoT Core?
I have tried connecting flutter mobile application with thing certificate just to see if such communication is even possible, which proved that it is.