* filer: add filer.options.disable_remote_storage_deletion for cache-only deletes
Deleting a filer entry under a remote.mount path also deletes the backing
object from the remote store (maybeDeleteFromRemote). Deployments that use a
remote mount as a read-through cache in front of an authoritative,
externally-managed object store cannot allow this: the filer typically holds
read-only credentials, so the remote delete fails and the entire delete
errors out; and even where it would succeed, it destroys data the filer does
not own.
Add filer.options.disable_remote_storage_deletion (default false, so existing
behaviour is unchanged). When enabled, maybeDeleteFromRemote is skipped for
both single-entry and recursive folder deletes: local metadata and cached
chunks are still removed, but the remote object is left intact.
* filer: assert local removal in cache-only recursive delete test
The recursive cache-only delete test only checked that no remote delete
happened; it did not verify the local child and directory entries were
removed. Add FindEntry assertions so a regression that skips local
recursive deletion is caught.
* filer: reload the remote mount mapping when /etc/remote changes
The mapping was only read at startup, so remote.unmount left the mount live
in the filer: the purge that follows the mapping delete then went to the
remote store and wiped every object under the mount.
Rebuild the rules trie and the conf map from scratch on each load, since
ptrie cannot drop a key, and swap them under a lock.
* filer: drop the filer-wide remote deletion switch
With the mapping reloaded on unmount, the purge no longer reaches the remote
store, so there is nothing left for the switch to protect against.
---------
Co-authored-by: Chris Lu <chris.lu@gmail.com>
* refactor: extract remote mount resolution into shared helpers
* refactor: share the adaptive remote cache wait policy
* filer: stream cold remote reads from the origin while caching
* s3: stream cold remote reads from the origin instead of 503 retries
* test: cover the S3 origin stream-through path
* remote mounts: match on path components and prefer the longest mount
* fail short origin streams instead of silently truncating
* s3: try the origin before failing a cold read on a local cache error
* s3: gate origin streaming on the entry's resolved version
* return the cache RPC's NotFound as a canonical status and classify it everywhere
* filer: keep multipart-range cold reads on the retry path
* Add remote storage index for lazy metadata pull
Introduces remoteStorageIndex, which maintains a map of filer directory
to remote storage client/location, refreshed periodically from the
filer's mount mappings. Provides lazyFetchFromRemote, ensureRemoteEntryInFiler,
and isRemoteBacked on S3ApiServer as integration points for handler-level
work in a follow-up PR. Nothing is wired into the server yet.
Made-with: Cursor
* Add unit tests for remote storage index and wire field into S3ApiServer
Adds tests covering isEmpty, findForPath (including longest-prefix
resolution), and isRemoteBacked. Also removes a stray PR review
annotation from the index file and adds the remoteStorageIdx field
to S3ApiServer so the package compiles ahead of the wiring PR.
Made-with: Cursor
* Address review comments on remote storage index
- Use filer_pb.CreateEntry helper so resp.Error is checked, not just the RPC error
- Extract keepPrev closure to remove duplicated error-handling in refresh loop
- Add comment explaining availability-over-consistency trade-off on filer save failure
Made-with: Cursor
* Move lazy metadata pull from S3 API to filer
- Add maybeLazyFetchFromRemote in filer: on FindEntry miss, stat remote
and CreateEntry when path is under a remote mount
- Use singleflight for dedup; context guard prevents CreateEntry recursion
- Availability-over-consistency: return in-memory entry if CreateEntry fails
- Add longest-prefix test for nested mounts in remote_storage_test.go
- Remove remoteStorageIndex, lazyFetchFromRemote, ensureRemoteEntryInFiler,
doLazyFetch from s3api; filer now owns metadata operations
- Add filer_lazy_remote_test.go with tests for hit, miss, not-found,
CreateEntry failure, longest-prefix, and FindEntry integration
Made-with: Cursor
* Address review: fix context guard test, add FindMountDirectory comment, remove dead code
Made-with: Cursor
* Nitpicks: restore prev maker in registerStubMaker, instance-scope lazyFetchGroup, nil-check remoteEntry
Made-with: Cursor
* Fix remotePath when mountDir is root: ensure relPath has leading slash
Made-with: Cursor
* filer: decouple lazy-fetch persistence from caller context
Use context.Background() inside the singleflight closure for CreateEntry
so persistence is not cancelled when the winning request's context is
cancelled. Fixes CreateEntry failing for all waiters when the first
caller times out.
Made-with: Cursor
* filer: remove redundant Mode bitwise OR with zero
Made-with: Cursor
* filer: use bounded context for lazy-fetch persistence
Replace context.Background() with context.WithTimeout(30s) and defer
cancel() to prevent indefinite blocking and release resources.
Made-with: Cursor
* filer: use checked type assertion for singleflight result
Made-with: Cursor
* filer: rename persist context vars to avoid shadowing function parameter
Made-with: Cursor
