feat: add storage_class, requester_pays, object_tags, and extra_s3_args config options

[Jenia3377543]

Problem

Users running DVC against S3-compatible providers (MinIO, Scaleway, Ceph, DigitalOcean Spaces, etc.) often need to control per-object S3 parameters — most commonly StorageClass — that the provider requires or that differs from the AWS default. There was no way to set these through DVC config; values were silently ignored.

Solution

Four new dvc remote modify config parameters that map into s3_additional_kwargs, which s3fs forwards to every boto3 write call:

Config key	boto3 key	Notes
storage_class	StorageClass	e.g. STANDARD, REDUCED_REDUNDANCY, or provider-specific class
requester_pays	RequestPayer	Boolean; sets value to "requester" for requester-pays buckets
object_tags	Tagging	URL-encoded key=value pairs, e.g. env=prod&team=ml
extra_s3_args	merged into kwargs	Generic JSON escape hatch for any other boto3 S3 write param; overrides named params on key collision

None-valued keys are filtered out by the existing flatten/unflatten logic so unset params do not pollute the dict.

Usage

dvc remote modify myremote storage_class REDUCED_REDUNDANCY
dvc remote modify myremote requester_pays true
dvc remote modify myremote object_tags "env=prod&team=ml"
# or for anything not natively supported:
dvc remote modify myremote extra_s3_args '{"StorageClass": "WARM"}'

Tests

11 new unit tests — 20/20 passing. Covers each new param, the not-set case, JSON error handling, and extra_s3_args overriding a named param.

Docs PR: iterative/dvc.org (link to follow)

[CLAassistant]

All committers have signed the CLA.

[Jenia3377543]

Hi @skshetry !

We're using DVC with an S3-compatible storage provider that requires setting a custom StorageClass (and occasionally other boto3 write
parameters) on uploaded objects. There was no way to do this through DVC config — the values were silently ignored.

This PR adds four new dvc remote modify options that map directly into s3_additional_kwargs (forwarded by s3fs to every boto3 write call):

• storage_class → StorageClass
• requester_pays → RequestPayer
• object_tags → Tagging
• extra_s3_args → generic JSON dict for anything not covered by the named options

All existing tests pass and 11 new unit tests are included. A matching docs PR is open at treeverse/dvc.org#5582.

Would really appreciate a review and, if everything looks good, a patch release so we can start using this upstream. Happy to adjust anything. Thanks!