title: S3 direct bucket upload: success but file not there
body: <p>I'm uploading a file directly to an S3 bucket using a multipart form upload and a signed policy (with AWS Signature Version 2), as explained <a href="http://docs.aws.amazon.com/AmazonS3/latest/dev/UsingHTTPPOST.html" rel="noreferrer">here</a> and <a href="http://docs.aws.amazon.com/AmazonS3/latest/dev/HTTPPOSTExamples.html" rel="noreferrer">here</a>.</p>
  
  <p>The upload is successful (I get redirected to the success_action_redirect URL) but the file is not visible in the bucket, under the key it should be. Though the ACL of the uploaded file was set to <code>public-read</code>, I thought it might be a permission issue, but even the owner of the bucket does not see the file.</p>
  
  <p>Does someone have a hint at might be wrong?</p>
  
  <p>Thank you.</p>