A remote created through the API without `mutable_ttl` was stored as 0, so its mutable paths never refreshed. With `check_mutable`, the ETag expired together with the freshness key, so an expired mutable path was always refetched in full and never revalidated.
- default an omitted `mutable_ttl` to 3600 on create; keep the stored value on update; explicit 0 still means never expire
- keep mutable ETags for `max(10 × mutable_ttl, 7d)`, re-armed on each 304, only when `check_mutable` is set and `mutable_ttl` is non-zero
- drop the stored ETag when a refetch returns none; never store one for immutable paths
- flush a remote's Redis keys on delete
- update docs/common/caching.md
Reviewed-on: #151
Co-authored-by: unkin-agent <unkin-agent@unkin.net>
Co-committed-by: unkin-agent <unkin-agent@unkin.net>
Evicting a remote object only deleted its Postgres row. The S3 index and the Redis TTL/ETag keys survived, so stale mirror metadata such as EPEL repodata kept being served.
- evict the artifact row, S3 index and Redis keys via `Engine.Evict`
- evict a directory with `<dir>/*`; other wildcards return 400, unknown remotes 404
- wait on the per-path fetch lock for single-path evicts; return 503 on timeout or a Redis error
- wildcard evicts take no lock; a fetch already in flight may re-cache its path
- return S3 list errors from `DeletePrefix` instead of deleting nothing
Reviewed-on: #128
Co-authored-by: unkin-agent <unkin-agent@unkin.net>
Co-committed-by: unkin-agent <unkin-agent@unkin.net>
unkin-agent