dwilkie/carrierwave_direct — pull request #20 by ericskiff (2012-03-25 18:27:43+00:00)
Title: S3 was rejecting Time.now.utc as a time format

Using carrierwave_direct out of the box with sinatra I was getting:

Invalid Policy: Invalid 'expiration' value
at upload time from S3

When changing the policy method to use Time.now.utc.iso8601 instead the uploads work.