both sides may open sync after reset

Ready nodes will leave the first message to the pear that isn't ready.
Hello and hello reply now carry ready, so readiness is known from the
very first contact, before any sync.  Together with the sync messages
and keepalives, reports_ready is always current.

After epoch switch, pings go to everyone except ready members already
on the new epoch, these learn from the lagging peer's opening.

2 files changed, 10 insertions, 0 deletions

diff --git a/src/transport/mod.rs b/src/transport/mod.rs
index d96b059..83c4e8d 100644
--- a/src/transport/mod.rs
+++ b/src/transport/mod.rs
@@ -118,6 +118,8 @@ pub struct HelloRequest {
     pub epoch: Epoch,
     /// Proof of the swarm key (`swarm::auth`); empty without one.
     pub auth: Vec<u8>,
+    /// The sender is ready (same meaning as `SyncEnvelope::ready`).
+    pub ready: bool,
 }
 
 #[derive(Debug, Clone)]
@@ -127,6 +129,8 @@ pub struct HelloReply {
     pub epoch: Epoch,
     /// Proof of the swarm key (`swarm::auth`); empty without one.
     pub auth: Vec<u8>,
+    /// The sender is ready.
+    pub ready: bool,
 }
 
 #[derive(Debug, Clone)]
diff --git a/src/transport/mycelium.rs b/src/transport/mycelium.rs
index 2406312..4a8a5a5 100644
--- a/src/transport/mycelium.rs
+++ b/src/transport/mycelium.rs
@@ -830,6 +830,7 @@ pub struct HelloRequestShadow {
     swarm_id: Option<String>,
     epoch: EpochShadow,
     auth: ByteBuf,
+    ready: bool,
 }
 
 #[derive(Serialize, Deserialize)]
@@ -842,6 +843,7 @@ pub struct HelloReplyShadow<'a> {
     epoch: EpochShadow,
     #[serde(default)]
     auth: ByteBuf,
+    ready: bool,
 }
 
 #[derive(Serialize, Deserialize)]
@@ -891,6 +893,7 @@ pub fn hello_request_to_bytes(msg: &HelloRequest) -> Result<Vec<u8>, rmp_serde::
         swarm_id: msg.swarm_id.clone(),
         epoch: epoch_to_shadow(&msg.epoch),
         auth: ByteBuf::from(msg.auth.clone()),
+        ready: msg.ready,
     })
 }
 pub fn bytes_to_hello_request(bytes: &[u8]) -> Result<HelloRequest, TransportError> {
@@ -899,6 +902,7 @@ pub fn bytes_to_hello_request(bytes: &[u8]) -> Result<HelloRequest, TransportErr
         swarm_id: shadow.swarm_id,
         epoch: epoch_from_shadow(shadow.epoch)?,
         auth: shadow.auth.into_vec(),
+        ready: shadow.ready,
     })
 }
 
@@ -909,6 +913,7 @@ pub fn hello_reply_to_bytes(msg: &HelloReply) -> Result<Vec<u8>, rmp_serde::enco
         peers: msg.peers.clone(), // Vec must be cloned for serialization wrapper matching
         epoch: epoch_to_shadow(&msg.epoch),
         auth: ByteBuf::from(msg.auth.clone()),
+        ready: msg.ready,
     };
     rmp_serde::to_vec(&shadow)
 }
@@ -919,6 +924,7 @@ pub fn bytes_to_hello_reply(bytes: &[u8]) -> Result<HelloReply, TransportError>
         peers: shadow.peers,
         epoch: epoch_from_shadow(shadow.epoch)?,
         auth: shadow.auth.into_vec(),
+        ready: shadow.ready,
     })
 }