>  I will add the expected response header

Thanks!

> but this test cannot test its presence since S3Client.putObject returns a boolean instead of the object
> metadata.

Ah, OK. Hm...so we have _no_ tests currently that cover that unmarshalling code? What API could would a user make to get the metadata back...a GET, I guess? Do we need to add some assertions to _that/those_ tests to figure out whether our new unmarshalling code works?