SERVER-34661 Return early when the vote request response has an error.

Fixed by making VoteRequester::Algorithm::processResponseto to check  ok field in the vote response message.

(cherry picked from commit e4e2162c489c1faa569463f51058ebc09368a5f9)

2 files changed, 44 insertions, 2 deletions

diff --git a/src/mongo/db/repl/vote_requester.cpp b/src/mongo/db/repl/vote_requester.cpp
index bac35602398..861b7b4b9e5 100644
--- a/src/mongo/db/repl/vote_requester.cpp
+++ b/src/mongo/db/repl/vote_requester.cpp
@@ -99,9 +99,14 @@ void VoteRequester::Algorithm::processResponse(const RemoteCommandRequest& reque
     }
     _responders.insert(request.target);
     ReplSetRequestVotesResponse voteResponse;
-    const auto status = voteResponse.initialize(response.data);
+    auto status = getStatusFromCommandResult(response.data);
+    if (status.isOK()) {
+        status = voteResponse.initialize(response.data);
+    }
     if (!status.isOK()) {
         logLine << "received an invalid response from " << request.target << ": " << status;
+        logLine << "; response message: " << response.data;
+        return;
     }
 
     if (voteResponse.getVoteGranted()) {
diff --git a/src/mongo/db/repl/vote_requester_test.cpp b/src/mongo/db/repl/vote_requester_test.cpp
index 1dd97c456ea..02adb0a919a 100644
--- a/src/mongo/db/repl/vote_requester_test.cpp
+++ b/src/mongo/db/repl/vote_requester_test.cpp
@@ -31,6 +31,7 @@
 #include <memory>
 
 #include "mongo/base/status.h"
+#include "mongo/db/commands.h"
 #include "mongo/db/jsobj.h"
 #include "mongo/db/repl/repl_set_request_votes_args.h"
 #include "mongo/db/repl/replication_executor.h"
@@ -109,7 +110,17 @@ protected:
     }
 
     void processResponse(const RemoteCommandRequest& request, const ResponseStatus& response) {
-        _requester->processResponse(request, response);
+        if (!response.isOK()) {
+            _requester->processResponse(request, response);
+            return;
+        }
+        BSONObjBuilder builder;
+        builder.appendElements(response.data);
+        // Appends ok:1.0 (status ok) to response data if 'ok' field is missing.
+        Command::appendCommandStatus(builder, Status::OK());
+        ResponseStatus responseWithCmdStatus = response;
+        responseWithCmdStatus.data = builder.obj();
+        _requester->processResponse(request, responseWithCmdStatus);
     }
 
     int getNumResponders() {
@@ -140,6 +151,19 @@ protected:
             NetworkInterfaceMock::Response(response.toBSON(), BSONObj(), Milliseconds(10)));
     }
 
+    ResponseStatus votedYesStatusNotOkBecauseFailedToStoreLastVote() {
+        ReplSetRequestVotesResponse response;
+        BSONObjBuilder result;
+        response.setVoteGranted(true);
+        response.setTerm(1);
+        response.addToBSON(&result);
+        auto status =
+            Status(ErrorCodes::InterruptedDueToReplStateChange, "operation was interrupted");
+        Command::appendCommandStatus(result, status);
+        return ResponseStatus(
+            NetworkInterfaceMock::Response(result.obj(), BSONObj(), Milliseconds(10)));
+    }
+
     ResponseStatus votedNoBecauseConfigVersionDoesNotMatch() {
         ReplSetRequestVotesResponse response;
         response.setVoteGranted(false);
@@ -236,6 +260,19 @@ TEST_F(VoteRequesterTest, ImmediateGoodResponseWinElection) {
     ASSERT_EQUALS(1, getNumResponders());
 }
 
+TEST_F(VoteRequesterTest, VoterFailedToStoreLastVote) {
+    startCapturingLogMessages();
+    ASSERT_FALSE(hasReceivedSufficientResponses());
+    processResponse(requestFrom("host1"), votedYesStatusNotOkBecauseFailedToStoreLastVote());
+    ASSERT_FALSE(hasReceivedSufficientResponses());
+    ASSERT_EQUALS(1, countLogLinesContaining("received an invalid response from host1:27017"));
+    processResponse(requestFrom("host2"), votedYes());
+    ASSERT_TRUE(hasReceivedSufficientResponses());
+    ASSERT(VoteRequester::Result::kSuccessfullyElected == getResult());
+    ASSERT_EQUALS(2, getNumResponders());
+    stopCapturingLogMessages();
+}
+
 TEST_F(VoteRequesterTest, BadConfigVersionWinElection) {
     startCapturingLogMessages();
     ASSERT_FALSE(hasReceivedSufficientResponses());