add epoch catch-up / snapshots

1 files changed, 18 insertions, 0 deletions

diff --git a/src/compaction/mod.rs b/src/compaction/mod.rs
index 69c633e..e97d9c8 100644
--- a/src/compaction/mod.rs
+++ b/src/compaction/mod.rs
@@ -4,6 +4,7 @@
 //! * `records`: the replicated compaction records under `_continuum/compactions/<id>`.
 //! * `coordinator`: proposal, settle period and decision on the node that was asked.
 //! * `switch`: switching this node to a committed epoch (worker).
+//! * `catchup`: fetching a newer epoch from a peer (late, new or failed nodes).
 //! * `delta`: replaying this node's changes since the base into the new epoch.
 //! * `local`: per-node in-memory state (prebuilt snapshots, switch status, archive).
 //! * `api`: `/admin/compaction(s)` handlers.
@@ -12,6 +13,7 @@
 //! depends on `AppState`, peers or sync internals.
 
 mod api;
+mod catchup;
 mod coordinator;
 mod delta;
 mod local;
@@ -19,6 +21,7 @@ mod records;
 pub(crate) mod snapshot;
 mod switch;
 
+pub(crate) use catchup::{receive_snapshot_reply, serve_snapshot};
 pub(crate) use local::Compaction;
 pub(crate) use switch::run_worker;
 
@@ -35,6 +38,7 @@ use tokio::sync::broadcast;
 
 use crate::replica::Epoch;
 use crate::sync::ChangeSet;
+use crate::transport::ParsedMessage;
 
 /// What compaction needs from the node. Implemented by `AppState`.
 ///
@@ -57,6 +61,16 @@ pub(crate) trait Host: Clone + Send + Sync + 'static {
     /// Known (not forgotten) peers.
     fn peer_summaries(&self) -> impl Future<Output = Vec<PeerSummary>> + Send;
 
+    /// True if `peer` completed the handshake as a member of our cluster.
+    fn is_cluster_member(&self, peer: &str) -> impl Future<Output = bool> + Send;
+
+    /// Sends a message to a peer over the transport.
+    fn send_message(
+        &self,
+        peer: &str,
+        message: ParsedMessage,
+    ) -> impl Future<Output = anyhow::Result<()>> + Send;
+
     /// Store paths touched by each published document change.
     fn subscribe_changes(&self) -> broadcast::Receiver<Arc<ChangeSet>>;
 
@@ -97,6 +111,10 @@ pub(crate) struct PeerSummary {
     pub(crate) id: String,
     /// Not dormant.
     pub(crate) active: bool,
+    /// Handshake completed.
+    pub(crate) established: bool,
+    /// The epoch the peer last advertised.
+    pub(crate) epoch: Option<Epoch>,
 }
 
 /// Admin routes. Merged into the authenticated part of the node's router.