From 98107fdf5c251949da8f21df81ced6377ca630d4 Mon Sep 17 00:00:00 2001
From: Little-Wallace <bupt2013211450@gmail.com>
Date: Sun, 30 Aug 2020 22:24:20 +0800
Subject: [PATCH] do not send messages

Signed-off-by: Little-Wallace <bupt2013211450@gmail.com>
---
 src/raft.rs | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/src/raft.rs b/src/raft.rs
index 501a185fa..7b73d8a56 100644
--- a/src/raft.rs
+++ b/src/raft.rs
@@ -128,6 +128,9 @@ pub struct Raft<T: Storage> {
     /// The list of messages.
     pub msgs: Vec<Message>,
 
+    /// The list of heartbeat messages.
+    pub heartbeats: Vec<Message>,
+
     /// The leader id
     pub leader_id: u64,
 
@@ -246,6 +249,7 @@ impl<T: Storage> Raft<T> {
             election_timeout: c.election_tick,
             votes: Default::default(),
             msgs: Default::default(),
+            heartbeats: Default::default(),
             leader_id: Default::default(),
             lead_transferee: None,
             term: Default::default(),
@@ -710,10 +714,12 @@ impl<T: Storage> Raft<T> {
         m.set_msg_type(MessageType::MsgHeartbeat);
         let commit = cmp::min(pr.matched, self.raft_log.committed);
         m.commit = commit;
+        m.from = self.id;
+        m.term = self.term;
         if let Some(context) = ctx {
             m.context = context;
         }
-        self.send(m);
+        self.heartbeats.push(m);
     }
 
     /// Sends RPC, with entries to all peers that are not up-to-date
@@ -2005,7 +2011,16 @@ impl<T: Storage> Raft<T> {
         to_send.to = m.from;
         to_send.context = m.take_context();
         to_send.commit = self.raft_log.committed;
-        self.send(to_send);
+        if self.raft_log.committed > self.raft_log.store.last_index().unwrap()
+        {
+            // If there is some entries that has committed in memory but not persisted, the message
+            // shall not be sent until all entries before committed_index have been persisted.
+            self.send(to_send);
+        } else {
+            to_send.term = self.term;
+            to_send.from = self.id;
+            self.heartbeats.push(to_send);
+        }
     }
 
     fn handle_snapshot(&mut self, mut m: Message) {