Nodes would stabilize on different encoding formats for the values,
some having the pre-migration format and some having the post-migration
format. This would be reflected in the Merkle trees never converging
and thus having an infinite resync loop.
Implement ListMultipartUploads, also refactor ListObjects and ListObjectsV2.
It took me some times as I wanted to propose the following things:
- Using an iterator instead of the loop+goto pattern. I find it easier to read and it should enable some optimizations. For example, when consuming keys of a common prefix, we do many [redundant checks](https://git.deuxfleurs.fr/Deuxfleurs/garage/src/branch/main/src/api/s3_list.rs#L125-L156) while the only thing to do is to [check if the following key is still part of the common prefix](https://git.deuxfleurs.fr/Deuxfleurs/garage/src/branch/feature/s3-multipart-compat/src/api/s3_list.rs#L476).
- Try to name things (see ExtractionResult and RangeBegin enums) and to separate concerns (see ListQuery and Accumulator)
- An IO closure to make unit tests possibles.
- Unit tests, to track regressions and document how to interact with the code
- Integration tests with `s3api`. In the future, I would like to move them in Rust with the aws rust SDK.
Merging of the logic of ListMultipartUploads and ListObjects was not a goal but a consequence of the previous modifications.
Some points that we might want to discuss:
- ListObjectsV1, when using pagination and delimiters, has a weird behavior (it lists multiple times the same prefix) with `aws s3api` due to the fact that it can not use our optimization to skip the whole prefix. It is independant from my refactor and can be tested with the commented `s3api` tests in `test-smoke.sh`. It probably has the same weird behavior on the official AWS S3 implementation.
- Considering ListMultipartUploads, I had to "abuse" upload id marker to support prefix skipping. I send an `upload-id-marker` with the hardcoded value `include` to emulate your "including" token.
- Some ways to test ListMultipartUploads with existing software (my tests are limited to s3api for now).
Co-authored-by: Quentin Dufour <quentin@deuxfleurs.fr>
Reviewed-on: Deuxfleurs/garage#171
Co-authored-by: Quentin <quentin@dufour.io>
Co-committed-by: Quentin <quentin@dufour.io>
