ENG-2815: Fix TransactionManager destruction

Summary:
TransactionManager pointer to implementation becomes null before actual destruction of implementation.
And during this process, it is possible, that RPC callbacks would communicate with TransactionManager.
To address this issue added call to Rpcs::Shutdown, before destroying TransactionManager.

Test Plan: ybd --cxx-test client_ql-transaction-test --gtest_filter QLTransactionTest.ReadRestart -n 100

Reviewers: robert, timur, mikhail

Reviewed By: mikhail

Subscribers: ybase

Differential Revision: https://phabricator.dev.yugabyte.com/D4150

src/yb/client/ql-transaction-test.cc

@@ -312,39 +312,55 @@ TEST_F(QLTransactionTest, Simple) {
   ASSERT_OK(cluster_->RestartSync());
 }
 
+// Commit flags says whether we should commit write txn during this test.
 void QLTransactionTest::TestReadRestart(bool commit) {
   google::FlagSaver saver;
 
   FLAGS_max_clock_skew_usec = 250000;
 
-  auto write_txn = CreateTransaction();
-  WriteRows(CreateSession(write_txn));
-  if (commit) {
-    ASSERT_OK(write_txn->CommitFuture().get());
-  }
-
-  server::TestClockDeltaChanger delta_changer(-100ms, clock_);
-  auto txn1 = CreateTransaction();
-  auto session = CreateSession(txn1);
-  if (commit) {
-    for (size_t r = 0; r != kNumRows; ++r) {
-      auto row = SelectRow(session, KeyForTransactionAndIndex(0, r));
-      ASSERT_NOK(row);
-      ASSERT_EQ(ql::ErrorCode::RESTART_REQUIRED, ql::GetErrorCode(row.status()))
-                    << "Bad row: " << row;
-    }
-    auto txn2 = txn1->CreateRestartedTransaction();
-    session->SetTransaction(txn2);
-    for (size_t r = 0; r != kNumRows; ++r) {
-      auto row = SelectRow(session, KeyForTransactionAndIndex(0, r));
-      ASSERT_OK(row);
-      ASSERT_EQ(ValueForTransactionAndIndex(0, r, WriteOpType::INSERT), *row);
+  {
+    auto write_txn = CreateTransaction();
+    WriteRows(CreateSession(write_txn));
+    if (commit) {
+      ASSERT_OK(write_txn->CommitFuture().get());
     }
-    VerifyData();
-  } else {
-    for (size_t r = 0; r != kNumRows; ++r) {
-      auto row = SelectRow(session, KeyForTransactionAndIndex(0, r));
-      ASSERT_TRUE(!row.ok() && row.status().IsNotFound()) << "Bad row: " << row;
+    BOOST_SCOPE_EXIT(write_txn, commit) {
+      if (!commit) {
+        write_txn->Abort();
+      }
+    } BOOST_SCOPE_EXIT_END;
+
+    server::TestClockDeltaChanger delta_changer(-100ms, clock_);
+    auto txn1 = CreateTransaction();
+    BOOST_SCOPE_EXIT(txn1, commit) {
+      if (!commit) {
+        txn1->Abort();
+      }
+    } BOOST_SCOPE_EXIT_END;
+    auto session = CreateSession(txn1);
+    if (commit) {
+      for (size_t r = 0; r != kNumRows; ++r) {
+        auto row = SelectRow(session, KeyForTransactionAndIndex(0, r));
+        ASSERT_NOK(row);
+        ASSERT_EQ(ql::ErrorCode::RESTART_REQUIRED, ql::GetErrorCode(row.status()))
+                      << "Bad row: " << row;
+      }
+      auto txn2 = txn1->CreateRestartedTransaction();
+      BOOST_SCOPE_EXIT(txn2) {
+        txn2->Abort();
+      } BOOST_SCOPE_EXIT_END;
+      session->SetTransaction(txn2);
+      for (size_t r = 0; r != kNumRows; ++r) {
+        auto row = SelectRow(session, KeyForTransactionAndIndex(0, r));
+        ASSERT_OK(row);
+        ASSERT_EQ(ValueForTransactionAndIndex(0, r, WriteOpType::INSERT), *row);
+      }
+      VerifyData();
+    } else {
+      for (size_t r = 0; r != kNumRows; ++r) {
+        auto row = SelectRow(session, KeyForTransactionAndIndex(0, r));
+        ASSERT_TRUE(!row.ok() && row.status().IsNotFound()) << "Bad row: " << row;
+      }
     }
   }
 

src/yb/client/transaction_manager.cc

@@ -154,6 +154,10 @@ class TransactionManager::Impl {
     clock_->Update(time);
   }
 
+  void Shutdown() {
+    rpcs_.Shutdown();
+  }
+
  private:
   YBClientPtr client_;
   scoped_refptr<ClockBase> clock_;
@@ -169,6 +173,7 @@ TransactionManager::TransactionManager(
     : impl_(new Impl(client, clock)) {}
 
 TransactionManager::~TransactionManager() {
+  impl_->Shutdown();
 }
 
 void TransactionManager::PickStatusTablet(PickStatusTabletCallback callback) {