Module applied_watcher 

Per-Raft-group applied-index watchers.

A single primitive — AppliedIndexWatcher — tracks the highest log index applied on this node for one Raft group. The GroupAppliedWatchers registry indexes one watcher per group so callers (proposers, consistent reads, lease renewals, recovery checks) can wait on the apply watermark of their group rather than only the metadata group.

Bump points (single source of truth for “applied on this node”):

1. crate::raft_loop::tick after the per-group apply phase — covers regular committed-entry application for every locally mounted group, including the metadata group.
2. crate::raft_loop::handle_rpc after handle_install_snapshot — covers the snapshot-install path where last_applied jumps to last_included_index without going through the apply loop.

Both bump points read the canonical applied index from the Raft node itself rather than mirroring it from a side channel, so the watcher cannot drift from Raft’s own state.

Re-exports

pub use registry::GroupAppliedWatchers;

pub use watcher::AppliedIndexWatcher;

pub use watcher::WaitOutcome;

Modules

registry

Per-group registry of AppliedIndexWatchers.

watcher

Sync wait primitive used to block on a Raft group’s local apply watermark.