SERVER-7681 Report majority number in ReplSetGetStatus

(cherry picked from commit 4b985d5460a2ddb889942f3b4ede04d7051b3921)

SERVER-7681 Report write majority in ReplSetGetStatus

(cherry picked from commit f92cc6fbdd660015f746ea3f59abfd4fb5485071)

2 files changed, 48 insertions, 0 deletions

diff --git a/src/mongo/db/repl/topology_coordinator.cpp b/src/mongo/db/repl/topology_coordinator.cpp
index b57480c4836..9d4e1235ba6 100644
--- a/src/mongo/db/repl/topology_coordinator.cpp
+++ b/src/mongo/db/repl/topology_coordinator.cpp
@@ -1608,6 +1608,9 @@ void TopologyCoordinator::prepareStatusResponse(const ReplSetStatusArgs& rsStatu
     response->append("heartbeatIntervalMillis",
                      durationCount<Milliseconds>(_rsConfig.getHeartbeatInterval()));
 
+    response->append("majorityVoteCount", _rsConfig.getMajorityVoteCount());
+    response->append("writeMajorityCount", _rsConfig.getWriteMajority());
+
     // New optimes, to hold them all.
     BSONObjBuilder optimes;
     _lastCommittedOpTimeAndWallTime.opTime.append(&optimes, "lastCommittedOpTime");
diff --git a/src/mongo/db/repl/topology_coordinator_v1_test.cpp b/src/mongo/db/repl/topology_coordinator_v1_test.cpp
index 388b8e84dc1..9dd69ddd6cb 100644
--- a/src/mongo/db/repl/topology_coordinator_v1_test.cpp
+++ b/src/mongo/db/repl/topology_coordinator_v1_test.cpp
@@ -1704,6 +1704,8 @@ TEST_F(TopoCoordTest, ReplSetGetStatus) {
     ASSERT_FALSE(selfStatus.hasField("pingMs"));
 
     ASSERT_EQUALS(2000, rsStatus["heartbeatIntervalMillis"].numberInt());
+    ASSERT_EQUALS(3, rsStatus["majorityVoteCount"].numberInt());
+    ASSERT_EQUALS(3, rsStatus["writeMajorityCount"].numberInt());
     ASSERT_BSONOBJ_EQ(initialSyncStatus, rsStatus["initialSyncStatus"].Obj());
     ASSERT_BSONOBJ_EQ(electionCandidateMetrics, rsStatus["electionCandidateMetrics"].Obj());
 
@@ -1727,6 +1729,49 @@ TEST_F(TopoCoordTest, ReplSetGetStatus) {
     ASSERT_FALSE(rsStatus.hasField("electionCandidateMetrics"));
 }
 
+TEST_F(TopoCoordTest, ReplSetGetStatusWriteMajorityDifferentFromMajorityVoteCount) {
+    // This tests that writeMajorityCount differs from majorityVoteCount in replSetGetStatus when
+    // the number of non-arbiter voters is less than majorityVoteCount.
+    Date_t startupTime = Date_t::fromMillisSinceEpoch(100);
+    Date_t heartbeatTime = Date_t::fromMillisSinceEpoch(5000);
+    Seconds uptimeSecs(10);
+    Date_t curTime = heartbeatTime + uptimeSecs;
+    OpTime readConcernMajorityOpTime(Timestamp(4, 1), 20);
+    Date_t readConcernMajorityWallTime = Date_t() + Seconds(readConcernMajorityOpTime.getSecs());
+    BSONObj initialSyncStatus = BSON("failedInitialSyncAttempts" << 1);
+    std::string setName = "mySet";
+
+    updateConfig(BSON("_id" << setName << "version" << 1 << "members"
+                            << BSON_ARRAY(BSON("_id" << 0 << "host"
+                                                     << "test0:1234")
+                                          << BSON("_id" << 1 << "host"
+                                                        << "test1:1234")
+                                          << BSON("_id" << 2 << "host"
+                                                        << "test2:1234"
+                                                        << "arbiterOnly" << true)
+                                          << BSON("_id" << 3 << "host"
+                                                        << "test3:1234"
+                                                        << "arbiterOnly" << true))),
+                 3,
+                 startupTime + Milliseconds(1));
+
+    BSONObjBuilder statusBuilder;
+    Status resultStatus(ErrorCodes::InternalError, "prepareStatusResponse didn't set result");
+    getTopoCoord().prepareStatusResponse(
+        TopologyCoordinator::ReplSetStatusArgs{
+            curTime,
+            static_cast<unsigned>(durationCount<Seconds>(uptimeSecs)),
+            {readConcernMajorityOpTime, readConcernMajorityWallTime},
+            initialSyncStatus},
+        &statusBuilder,
+        &resultStatus);
+    ASSERT_OK(resultStatus);
+    BSONObj rsStatus = statusBuilder.obj();
+    ASSERT_EQUALS(3, rsStatus["majorityVoteCount"].numberInt());
+    ASSERT_EQUALS(2, rsStatus["writeMajorityCount"].numberInt());
+}
+
+
 TEST_F(TopoCoordTest, ReplSetGetStatusIPs) {
     BSONObj initialSyncStatus = BSON("failedInitialSyncAttempts" << 1);
     std::string setName = "mySet";