SERVER-37245 Use the SessionCatalog to track sessions on MongoS

src/mongo/db/SConscript

@@ -2007,7 +2007,7 @@ env.CppUnitTest(
     LIBDEPS=[
         '$BUILD_DIR/mongo/unittest/concurrency',
         'auth/authmocks',
-        'service_context_d_test_fixture',
+        'service_context_test_fixture',
         'session_catalog',
     ],
 )

src/mongo/db/concurrency/locker_noop.h

@@ -116,7 +116,7 @@ class LockerNoop : public Locker {
     virtual void endWriteUnitOfWork() {}
 
     virtual bool inAWriteUnitOfWork() const {
-        MONGO_UNREACHABLE;
+        return false;
     }
 
     virtual LockResult lock(OperationContext* opCtx,

src/mongo/db/session_catalog_test.cpp

@@ -30,7 +30,7 @@
 
 #include "mongo/platform/basic.h"
 
-#include "mongo/db/service_context_d_test_fixture.h"
+#include "mongo/db/service_context_test_fixture.h"
 #include "mongo/db/session_catalog.h"
 #include "mongo/stdx/future.h"
 #include "mongo/stdx/memory.h"
@@ -42,7 +42,7 @@
 namespace mongo {
 namespace {
 
-class SessionCatalogTest : public ServiceContextMongoDTest {
+class SessionCatalogTest : public ServiceContextTest {
 protected:
     SessionCatalog* catalog() {
         return SessionCatalog::get(getServiceContext());

src/mongo/s/SConscript

@@ -57,17 +57,20 @@ env.Library(
         'cluster_commands_helpers.cpp',
         'multi_statement_transaction_requests_sender.cpp',
         'transaction_router.cpp',
+        'session_catalog_router.cpp',
     ],
     LIBDEPS=[
         '$BUILD_DIR/mongo/db/commands/txn_cmd_request',
         '$BUILD_DIR/mongo/db/curop',
-        '$BUILD_DIR/mongo/db/logical_session_id',
         '$BUILD_DIR/mongo/db/logical_session_id_helpers',
         '$BUILD_DIR/mongo/db/repl/read_concern_args',
         'async_requests_sender',
         'common_s',
         'grid',
     ],
+    LIBDEPS_PRIVATE=[
+        '$BUILD_DIR/mongo/db/session_catalog',
+    ],
 )
 
 env.Library(

src/mongo/s/commands/strategy.cpp

@@ -77,6 +77,7 @@
 #include "mongo/s/grid.h"
 #include "mongo/s/query/cluster_cursor_manager.h"
 #include "mongo/s/query/cluster_find.h"
+#include "mongo/s/session_catalog_router.h"
 #include "mongo/s/stale_exception.h"
 #include "mongo/s/transaction_router.h"
 #include "mongo/util/fail_point_service.h"
@@ -403,11 +404,11 @@ void runCommand(OperationContext* opCtx,
                 !readConcernArgs.getArgsAtClusterTime());
     }
 
-    boost::optional<ScopedRouterSession> scopedSession;
+    boost::optional<RouterOperationContextSession> routerSession;
     try {
         CommandHelpers::evaluateFailCommandFailPoint(opCtx, commandName);
         if (osi.getAutocommit()) {
-            scopedSession.emplace(opCtx);
+            routerSession.emplace(opCtx);
 
             auto txnRouter = TransactionRouter::get(opCtx);
             invariant(txnRouter);

src/mongo/s/compute_at_cluster_time_test.cpp

@@ -38,6 +38,7 @@
 #include "mongo/s/catalog_cache_test_fixture.h"
 #include "mongo/s/client/shard_remote.h"
 #include "mongo/s/cluster_commands_helpers.h"
+#include "mongo/s/session_catalog_router.h"
 #include "mongo/s/shard_id.h"
 #include "mongo/s/sharding_router_test_fixture.h"
 #include "mongo/s/transaction_router.h"
@@ -83,8 +84,6 @@ class AtClusterTimeTest : public ShardingTestFixture {
             repl::ReadConcernArgs(repl::ReadConcernLevel::kSnapshotReadConcern);
 
         _scopedSession.emplace(operationContext());
-
-        txnRouter()->checkOut();
         txnRouter()->beginOrContinueTxn(operationContext(), kTxnNumber, true);
     }
 
@@ -97,7 +96,7 @@ class AtClusterTimeTest : public ShardingTestFixture {
     }
 
 private:
-    boost::optional<ScopedRouterSession> _scopedSession;
+    boost::optional<RouterOperationContextSession> _scopedSession;
 };
 
 TEST_F(AtClusterTimeTest, ComputeValidValid) {
@@ -187,8 +186,6 @@ class AtClusterTimeTargetingTest : public CatalogCacheTestFixture {
             repl::ReadConcernArgs(repl::ReadConcernLevel::kSnapshotReadConcern);
 
         _scopedSession.emplace(operationContext());
-
-        txnRouter()->checkOut();
         txnRouter()->beginOrContinueTxn(operationContext(), kTxnNumber, true);
     }
 
@@ -201,7 +198,7 @@ class AtClusterTimeTargetingTest : public CatalogCacheTestFixture {
     }
 
 private:
-    boost::optional<ScopedRouterSession> _scopedSession;
+    boost::optional<RouterOperationContextSession> _scopedSession;
 };
 
 // Verifies that the latest in-memory logical time is returned when lastCommittedOpTime on one

src/mongo/unittest/unittest-inl.h → src/mongo/s/session_catalog_router.cpp

@@ -28,27 +28,17 @@
  *    it in the license file.
  */
 
-#pragma once
+#define MONGO_LOG_DEFAULT_COMPONENT ::mongo::logger::LogComponent::kSharding
 
-namespace mongo {
-namespace unittest {
+#include "mongo/platform/basic.h"
+
+#include "mongo/s/session_catalog_router.h"
 
-template <typename T>
-Test::RegistrationAgent<T>::RegistrationAgent(const std::string& suiteName,
-                                              const std::string& testName)
-    : _suiteName(suiteName), _testName(testName) {
-    Suite::getSuite(suiteName)->add<T>(testName);
-}
+namespace mongo {
 
-template <typename T>
-std::string Test::RegistrationAgent<T>::getSuiteName() const {
-    return _suiteName;
-}
+RouterOperationContextSession::RouterOperationContextSession(OperationContext* opCtx)
+    : _operationContextSession(opCtx) {}
 
-template <typename T>
-std::string Test::RegistrationAgent<T>::getTestName() const {
-    return _testName;
-}
+RouterOperationContextSession::~RouterOperationContextSession() = default;
 
 }  // namespace mongo
-}  // namespace unittest

src/mongo/s/session_catalog_router.h

@@ -0,0 +1,53 @@
+
+/**
+ *    Copyright (C) 2018-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the Server Side Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#pragma once
+
+#include "mongo/db/session_catalog.h"
+
+namespace mongo {
+
+/**
+ * Scoped object, which checks out the session specified in the passed operation context and stores
+ * it for later access by the command. The session is installed at construction time and is removed
+ * at destruction. This can only be used for multi-statement transactions.
+ */
+class RouterOperationContextSession {
+    MONGO_DISALLOW_COPYING(RouterOperationContextSession);
+
+public:
+    RouterOperationContextSession(OperationContext* opCtx);
+    ~RouterOperationContextSession();
+
+private:
+    OperationContextSession _operationContextSession;
+};
+
+}  // namespace mongo