mirror of
https://github.com/aptly-dev/aptly.git
synced 2026-01-11 03:11:50 +00:00
960cf76c42
The S3 backend relies on ETag S3 returns being equal to the MD5 of the object, but it’s not necessarily true. For that purpose we store the MD5 object in a separate metadata field as well to make sure it isn’t lost. From https://docs.aws.amazon.com/AmazonS3/latest/API/RESTCommonResponseHeaders.html: > The entity tag is a hash of the object. The ETag reflects changes only > to the contents of an object, not its metadata. The ETag may or may not > be an MD5 digest of the object data. Whether or not it depends on how > the object was created and how it is encrypted as described below: > > Objects created by the PUT Object, POST Object, or Copy operation, > or through the AWS Management Console, and are encrypted by SSE-S3 or > plaintext, have ETags that are an MD5 digest of their object data. > > Objects created by the PUT Object, POST Object, or Copy operation, > or through the AWS Management Console, and are encrypted by SSE-C or > SSE-KMS, have ETags that are not an MD5 digest of their object data. > > If an object is created by either the Multipart Upload or Part Copy > operation, the ETag is not an MD5 digest, regardless of the method > of encryption. Signed-off-by: Andrej Shadura <andrew.shadura@collabora.co.uk>