Method handle_append_entries

nodedb-raft/src/node/rpc/append_entries.rs:14–64

Handle incoming AppendEntries RPC.

(&mut self, req: &AppendEntriesRequest)

impl<S: LogStorage> RaftNode<S> {
    /// Handle incoming AppendEntries RPC.
    pub fn handle_append_entries(&mut self, req: &AppendEntriesRequest) -> AppendEntriesResponse {
        if req.term < self.hard_state.current_term {
            return AppendEntriesResponse {
                term: self.hard_state.current_term,
                success: false,
                last_log_index: self.log.last_index(),
            };
        }

        if req.term > self.hard_state.current_term || self.role == NodeRole::Candidate {
            // `become_follower` preserves Learner role — see internal.rs.
            self.become_follower(req.term);
        }

        self.leader_id = req.leader_id;
        self.reset_election_timeout();

        // Check prev_log consistency.
        if req.prev_log_index > 0 {
            match self.log.term_at(req.prev_log_index) {
                Some(term) if term == req.prev_log_term => {}
                _ => {
                    return AppendEntriesResponse {
                        term: self.hard_state.current_term,
                        success: false,
                        last_log_index: self.log.last_index(),
                    };
                }
            }
        }

        if let Err(e) = self.log.append_entries(req.prev_log_index, &req.entries) {
            warn!(group = self.config.group_id, error = %e, "append_entries failed");
            return AppendEntriesResponse {
                term: self.hard_state.current_term,
                success: false,
                last_log_index: self.log.last_index(),
            };
        }

        if req.leader_commit > self.volatile.commit_index {
            self.volatile.commit_index = req.leader_commit.min(self.log.last_index());
            self.collect_committed_entries();
        }

        AppendEntriesResponse {
            term: self.hard_state.current_term,
            success: true,
            last_log_index: self.log.last_index(),
        }
    }

    /// Handle AppendEntries response from a peer (leader only).
    ///