続報1(2019/06/17): 本記事公開後、以下の正式なアナウンスが公開されました🎉。これに油断せず、v4署名のライブラリにアップデートしましょう。 元記事: Amazon S3 Update – SigV2 Deprecation Period Extended & Modified | AWS News Blog Original Plan – Support for SigV2 ends on June 24, 2019. Revised Plan – Any new buckets created after June 24, 2020 will not support SigV2 signed requests, although existing buckets will continue to support SigV2 while we work with custo