diff options
Diffstat (limited to 'src/swarm/sync.rs')
| -rw-r--r-- | src/swarm/sync.rs | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/src/swarm/sync.rs b/src/swarm/sync.rs index de2d86d..10ebf9f 100644 --- a/src/swarm/sync.rs +++ b/src/swarm/sync.rs @@ -162,22 +162,32 @@ async fn deliver_sync_to_peer(state: &AppState, peer: &str) -> Result<()> { peer_state .sync .generate(&replica.doc, Instant::now(), bytes_before); - let body = message.map(|payload| { + let body = message.and_then(|payload| { if payload.0.len() <= delta_threshold { - return transport::SyncBody::Message(payload); + return Some(transport::SyncBody::Message(payload)); } // Too large for one message: all or nothing, and on a slow link // within the transport's delivery limit. The peer fetches it in // chunks. - let from = peer_state.sync.withdraw_for_delta(); + let from = peer_state.sync.withdraw_for_delta(Instant::now()); let spec = transport::DeltaSpec::new(from, replica.heads().to_vec()); + if spec.to.iter().all(|head| spec.from.contains(head)) { + // It has our heads: nothing to offer (Automerge thought it + // lacked what it has, as from a view of it that was old). + debug!( + message_bytes = payload.0.len(), + "Sync message too large, but the peer has our heads; not sent" + ); + peer_state.sync.nothing_to_send(); + return None; + } info!( message_bytes = payload.0.len(), from = spec.from.len(), to = spec.to.len(), "Sync message too large; offering the changes as a blob" ); - transport::SyncBody::Delta(spec) + Some(transport::SyncBody::Delta(spec)) }); let delivered = level && matches!(body, Some(transport::SyncBody::Message(_))); if delivered { |