SERVER-43904: Filter unelectable nodes during election handoff

1 files changed, 16 insertions, 0 deletions

diff --git a/src/mongo/db/repl/repl_set_heartbeat_response.cpp b/src/mongo/db/repl/repl_set_heartbeat_response.cpp
index 138f6c84e1e..c77d454f00c 100644
--- a/src/mongo/db/repl/repl_set_heartbeat_response.cpp
+++ b/src/mongo/db/repl/repl_set_heartbeat_response.cpp
@@ -63,6 +63,7 @@ const std::string kReplSetFieldName = "set";
 const std::string kSyncSourceFieldName = "syncingTo";
 const std::string kTermFieldName = "term";
 const std::string kTimestampFieldName = "ts";
+const std::string kIsElectableFieldName = "electable";
 
 }  // namespace
 
@@ -102,6 +103,9 @@ void ReplSetHeartbeatResponse::addToBSON(BSONObjBuilder* builder) const {
         _appliedOpTime.append(builder, kAppliedOpTimeFieldName);
         builder->appendDate(kAppliedWallTimeFieldName, _appliedWallTime);
     }
+    if (_electableSet) {
+        *builder << kIsElectableFieldName << _electable;
+    }
 }
 
 BSONObj ReplSetHeartbeatResponse::toBSON() const {
@@ -180,6 +184,13 @@ Status ReplSetHeartbeatResponse::initialize(const BSONObj& doc, long long term)
     _appliedWallTime = appliedWallTimeElement.Date();
     _appliedOpTimeSet = true;
 
+    status = bsonExtractBooleanField(doc, kIsElectableFieldName, &_electable);
+    if (!status.isOK()) {
+        _electableSet = false;
+    } else {
+        _electableSet = true;
+    }
+
     const BSONElement memberStateElement = doc[kMemberStateFieldName];
     if (memberStateElement.eoo()) {
         _stateSet = false;
@@ -300,5 +311,10 @@ OpTimeAndWallTime ReplSetHeartbeatResponse::getDurableOpTimeAndWallTime() const
     return {_durableOpTime, _durableWallTime};
 }
 
+bool ReplSetHeartbeatResponse::isElectable() const {
+    invariant(_electableSet);
+    return _electable;
+}
+
 }  // namespace repl
 }  // namespace mongo