Land the remaining notify-crate audit fixes.
backlog#979(b): remove_target now enforces the same bucket-binding guard as
remove_target_config, refusing to delete a target still referenced by a bucket
rule so notification rules are not left orphaned.
backlog#984:
- event.rs: an unversioned object omits versionId entirely instead of
serializing versionId:"" (empty object/request versions treated as "no
version").
- notifier.rs: RUSTFS_NOTIFY_SEND_CONCURRENCY=0 coerces back to the default
instead of building a zero-permit semaphore that deadlocks every dispatch;
init_bucket_targets_shared closes the replaced targets instead of dropping
them without close() (connection leak).
- subscriber_index.rs: store_snapshot uses an atomic compute_if_absent upsert,
removing the get-then-insert TOCTOU that could clobber a concurrent
first-writer's snapshot cell.
- pipeline.rs: send_event assigns the history sequence and broadcasts to live
subscribers under one critical section so broadcast order matches recorded
sequence order.
- xml_config.rs: filter value length is bounded by character count, not byte
length, so valid multi-byte keys are no longer wrongly rejected.
- global.rs: a losing initialize() race shuts the just-initialized system down
instead of leaking its targets/replay workers.
backlog#970 (notify part): reload_config stops the running replay workers
before activating the new ones, so old and new workers do not concurrently
drain the same persisted stores. The full signal+join shutdown lives in the
targets crate under the same issue.
Tests: added regression coverage for each fix.
cargo build -p rustfs-notify, cargo test -p rustfs-notify --lib (98 passed),
cargo clippy -p rustfs-notify --all-targets (clean).
Relates to rustfs/backlog#979
Relates to rustfs/backlog#984
Relates to rustfs/backlog#970
Co-authored-by: heihutu <heihutu@gmail.com>
`LiveEventHistory::snapshot_since` resumed from the oldest retained event
whenever a consumer's cursor pointed before it, without signaling that the
in-between events had been evicted from the ring buffer. Cursor-based
consumers therefore assumed the returned batch was contiguous with their
cursor and silently lost events.
Add a `gap` flag to `LiveEventBatch`, set when the consumer's cursor is
older than the oldest retained sequence, so consumers can detect the loss
and trigger a full re-sync or alert. Add a regression test that fills and
evicts past the ring-buffer capacity and asserts a lagging cursor reports
`gap = true` (and that contiguous/caught-up cursors do not).
Refs rustfs/backlog#969