kuilt-crdt/us.tractat.kuilt.crdt/EphemeralMapTracker

EphemeralMapTracker

class EphemeralMapTracker<V>(val ttlMs: Long, clock: () -> Long = defaultClock())

A stateful wrapper around EphemeralMap that stamps local receive times and drives TTL eviction.

Responsibilities

Maintains a mutable EphemeralMap state by merging inbound EphemeralMap updates via received.
Stamps a local receive time (via clock) whenever a replica's entry advances to a higher clock — i.e. only real updates reset the TTL, not stale re-deliveries.
Surfaces live: the set of entries not yet expired and not departed.

Clock contract

clock is a () -> Long that returns the current local monotonic time in milliseconds. The production default is kotlin.time.TimeSource.Monotonic. Tests inject a controlled counter so eviction can be driven deterministically without wall-clock dependencies.

Parameters

ttlMs

expiry window in milliseconds. An entry is considered expired when now - receiveTime >= ttlMs. The boundary is exclusive: exactly at ttlMs ms the entry is expired.

clock

injectable monotonic time source (milliseconds).