SERVER-34141 Reset client metadata when missing in metadata

(cherry picked from commit 52c1fe02a0cd0f64a4d97f7c1e17792b38c67ca4)

2 files changed, 25 insertions, 7 deletions

diff --git a/src/mongo/rpc/metadata/client_metadata_ismaster.cpp b/src/mongo/rpc/metadata/client_metadata_ismaster.cpp
index 234f61c78e8..8a6e84f2eef 100644
--- a/src/mongo/rpc/metadata/client_metadata_ismaster.cpp
+++ b/src/mongo/rpc/metadata/client_metadata_ismaster.cpp
@@ -65,17 +65,30 @@ const boost::optional<ClientMetadata>& ClientMetadataIsMasterState::getClientMet
     return _clientMetadata;
 }
 
-void ClientMetadataIsMasterState::setClientMetadata(
-    Client* client, boost::optional<ClientMetadata> clientMetadata) {
+void ClientMetadataIsMasterState::setClientMetadata(Client* client,
+                                                    boost::optional<ClientMetadata> clientMetadata,
+                                                    bool setViaMetadata) {
     auto& state = get(client);
 
     stdx::lock_guard<Client> lk(*client);
     state._clientMetadata = std::move(clientMetadata);
+    state._setViaMetadata = setViaMetadata;
 }
 
 
 Status ClientMetadataIsMasterState::readFromMetadata(OperationContext* txn, BSONElement& element) {
+    auto& clientMetadataIsMasterState = ClientMetadataIsMasterState::get(txn->getClient());
+
+    // If client metadata is not present in network requests, reset the in-memory metadata to be
+    // blank so that the wrong
+    // app name is not propagated.
     if (element.eoo()) {
+        auto client = txn->getClient();
+
+        if (clientMetadataIsMasterState._setViaMetadata && !client->isInDirectClient()) {
+            clientMetadataIsMasterState.setClientMetadata(client, boost::none, true);
+        }
+
         return Status::OK();
     }
 
@@ -85,10 +98,8 @@ Status ClientMetadataIsMasterState::readFromMetadata(OperationContext* txn, BSON
         return swParseClientMetadata.getStatus();
     }
 
-    auto& clientMetadataIsMasterState = ClientMetadataIsMasterState::get(txn->getClient());
-
-    clientMetadataIsMasterState.setClientMetadata(txn->getClient(),
-                                                  std::move(swParseClientMetadata.getValue()));
+    clientMetadataIsMasterState.setClientMetadata(
+        txn->getClient(), std::move(swParseClientMetadata.getValue()), true);
 
     return Status::OK();
 }
diff --git a/src/mongo/rpc/metadata/client_metadata_ismaster.h b/src/mongo/rpc/metadata/client_metadata_ismaster.h
index 305018343d0..73760abfead 100644
--- a/src/mongo/rpc/metadata/client_metadata_ismaster.h
+++ b/src/mongo/rpc/metadata/client_metadata_ismaster.h
@@ -59,7 +59,9 @@ public:
     /**
      * Set the optional client metadata object.
      */
-    static void setClientMetadata(Client* client, boost::optional<ClientMetadata> clientMetadata);
+    static void setClientMetadata(Client* client,
+                                  boost::optional<ClientMetadata> clientMetadata,
+                                  bool setViaMetadata = false);
 
     /**
      * Check a flag to indicate that isMaster has been seen for this Client.
@@ -102,6 +104,11 @@ private:
     // Thread-Safety:
     //   None - must be only be read and written from the thread owning "Client".
     bool _hasSeenIsMaster{false};
+
+    // Indicates whether we have set isMaster based on metadata or via isMaster
+    // Thread-Safety:
+    //   None - must be only be read and written from the thread owning "Client".
+    bool _setViaMetadata{false};
 };
 
 }  // namespace mongo