fix get peer info of removed membe

in nuobject test, a removed member will try to get the info of itself to
identify whether it is in a pg. but ATM , it is not in the configuration
of this raft group. this PR aims to handle this case.

what`s more, this PR add the commited_log_index to peer info, so that a
peer can get its last commited log index.

conanfile.py

@@ -10,7 +10,7 @@
 
 class NuRaftMesgConan(ConanFile):
     name = "nuraft_mesg"
-    version = "3.6.3"
+    version = "3.6.4"
 
     homepage = "https://github.com/eBay/nuraft_mesg"
     description = "A gRPC service for NuRAFT"

include/nuraft_mesg/mesg_state_mgr.hpp

@@ -37,6 +37,9 @@ struct peer_info {
     uint64_t last_log_idx_;
     // The elapsed time since the last successful response from this peer, set to 0 on leader
     uint64_t last_succ_resp_us_;
+    // The last committed log index that the peer has. this is only got by the node itself,
+    // a node can not get the last_commit_log_idx_ of other nodes.
+    uint64_t last_commit_log_idx_;
 };
 
 class repl_service_ctx {

src/lib/repl_service_ctx.cpp

@@ -107,16 +107,23 @@ std::vector< peer_info > repl_service_ctx::get_raft_status() const {
                 LOGW("do not find peer id  {} in the conifg of leader", pinfo.id_);
                 continue;
             }
-            peers.emplace_back(peer_info{std::string(peer_id), pinfo.last_log_idx_, pinfo.last_succ_resp_us_});
+            // from the view of leader, it can not get the last_commit_log_idx_ of other nodes, so set it to 0
+            peers.emplace_back(std::string(peer_id), pinfo.last_log_idx_, pinfo.last_succ_resp_us_, 0);
         }
     }
 
-    auto my_id = _server->get_id();
-    auto my_peer_id = _server->get_srv_config(my_id)->get_endpoint();
+    auto my_config = _server->get_srv_config(_server->get_id());
 
-    // add the peer info of itself(leader or follower) , which is useful for upper layer
-    // from the view a node itself, last_succ_resp_us_ make no sense, so set it to 0
-    peers.emplace_back(my_peer_id, _server->get_last_log_idx(), 0);
+    // if I am the removed memeber, I can not find myself in the configuration. this will happen when a removed member
+    // tries to get the raft status
+    if (my_config) {
+        auto my_peer_id = my_config->get_endpoint();
+
+        // add the peer info of itself(leader or follower) , which is useful for upper layer
+        // 1 from the view of a node itself, last_succ_resp_us_ make no sense, so set it to 0
+        // 2 from the view of a node itself, it can get the last_commit_log_idx_ of itself
+        peers.emplace_back(my_peer_id, _server->get_last_log_idx(), 0, _server->get_committed_log_idx());
+    }
 
     return peers;
 }