Module hints 

Node-local hinted-handoff store.

When a write request fans out to a peer in crate::cluster::peer::PeerState::Down or to a peer whose outbound channel is closed, the dispatcher records a hint: the on-the-wire request bytes, the index of the intended peer, and an absolute expiry deadline. A background task periodically:

• drains hints destined for any peer that has returned to crate::cluster::peer::PeerState::Normal and ships them over the same per-peer outbound channel the dispatcher would have used;
• drops hints that have aged past their hint_ttl_seconds so the in-memory store stays bounded.

The v1 store is RAM-only. The natural follow-up is an on-disk variant (one segment file per peer, replayed at startup); see docs/journal/2026-05-23-hinted-handoff.md for the deferral note.

Examples

use std::time::{Duration, Instant};
use dynomite::cluster::hints::HintStore;

let store = HintStore::new(1024);
store.enqueue(7, b"*3\r\n$3\r\nSET\r\n$1\r\nk\r\n$1\r\nv\r\n".to_vec(), Duration::from_secs(60))
    .expect("under capacity");
let drained = store.take_for(7);
assert_eq!(drained.len(), 1);
assert_eq!(store.expire_now(Instant::now()), 0);

Structs

Hint

One pending hint.

HintStore

Node-local hint store.

HintStoreStats

Snapshot of the store’s current size.

Enums

HintStoreError

Errors produced by HintStore::enqueue.