preWrite method

@override void preWrite(PHiveCtx ctx)

Attaches TTL metadata to the outgoing payload.

Skips null values — there is no meaningful expiry window to record for a field that holds no data, and writing TTL metadata for null would cause serializePayload to encode a non-null payload string for a null value.

Implementation

@override
/// Attaches TTL metadata to the outgoing payload.
///
/// Skips null values — there is no meaningful expiry window to record for a
/// field that holds no data, and writing TTL metadata for null would cause
/// [serializePayload] to encode a non-null payload string for a null value.
void preWrite(PHiveCtx ctx) {
  if (ctx.value == null) return;
  ctx.pendingMetadata['ttl_ms'] = durationSeconds * 1000;
  ctx.pendingMetadata['written_at'] = DateTime.now().millisecondsSinceEpoch;
}