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Changes between Initial Version and Version 1 of Ticket #11675, comment 13

initial	v1
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3	3	For Amazon S3 I've used a redirect to a [http://boto3.readthedocs.io/en/latest/guide/s3.html#generating-presigned-urls boto3.generate_presigned_url] for downloading files directly in a similar use-case. This seemed surprisingly simple. Direct uploading was a bit more complicated (client-side logic and a new server-side endpoint for [http://boto3.readthedocs.io/en/latest/guide/s3.html#generating-presigned-posts boto3.generate_presigned_post]).
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	5	(But for Trac it would probably be largely acceptable to route through the server for many installations where attachments are relatively small / infrequent.)