I have a simple template with 3 processors ListS3 -> FetchS3 -> LogAttribute and it is configured to let users input access key and secret key when they create a feed.
When I create a feed from this template and provide access key and secret key and run the feed. Kylo only set the FetchS3 credential to correct value. ListS3 always got the wrong credential.
When I edit the feed (e.g. edit feed schedule) credential in both FetchS3 and ListS3 processors are removed.
A reference to email thread can be found here https://groups.google.com/forum/#!topic/kylo-community/mx-k0rxjyj4
User was advised to try the documented method of AWSCredentialsService controller