SERVER-23973 Ensure config servers send the correct config server optime when talking to shards

16 files changed, 202 insertions, 50 deletions

diff --git a/src/mongo/db/s/sharding_connection_hook_for_mongod.cpp b/src/mongo/db/s/sharding_connection_hook_for_mongod.cpp
index d072045a79b..55abe671115 100644
--- a/src/mongo/db/s/sharding_connection_hook_for_mongod.cpp
+++ b/src/mongo/db/s/sharding_connection_hook_for_mongod.cpp
@@ -31,13 +31,13 @@
 
 #include "mongo/db/s/sharding_connection_hook_for_mongod.h"
 
-#include "mongo/s/sharding_egress_metadata_hook.h"
+#include "mongo/s/sharding_egress_metadata_hook_for_mongod.h"
 #include "mongo/stdx/memory.h"
 
 namespace mongo {
 
 ShardingConnectionHookForMongod::ShardingConnectionHookForMongod(bool shardedConnections)
     : ShardingConnectionHook(shardedConnections,
-                             stdx::make_unique<rpc::ShardingEgressMetadataHook>()){};
+                             stdx::make_unique<rpc::ShardingEgressMetadataHookForMongod>()){};
 
 }  // namespace mongo
diff --git a/src/mongo/db/s/sharding_initialization_mongod.cpp b/src/mongo/db/s/sharding_initialization_mongod.cpp
index 561a0ddc29c..fc75b886961 100644
--- a/src/mongo/db/s/sharding_initialization_mongod.cpp
+++ b/src/mongo/db/s/sharding_initialization_mongod.cpp
@@ -39,6 +39,7 @@
 #include "mongo/s/client/shard_remote.h"
 #include "mongo/s/client/shard_local.h"
 #include "mongo/s/client/shard_factory.h"
+#include "mongo/s/sharding_egress_metadata_hook_for_mongod.h"
 #include "mongo/s/sharding_initialization.h"
 #include "mongo/stdx/memory.h"
 
@@ -75,6 +76,9 @@ Status initializeGlobalShardingStateForMongod(const ConnectionString& configCS)
         stdx::make_unique<ShardFactory>(std::move(buildersMap), std::move(targeterFactory));
 
     return initializeGlobalShardingState(
-        configCS, ChunkSizeSettingsType::kDefaultMaxChunkSizeBytes, std::move(shardFactory), false);
+        configCS,
+        ChunkSizeSettingsType::kDefaultMaxChunkSizeBytes,
+        std::move(shardFactory),
+        []() { return stdx::make_unique<rpc::ShardingEgressMetadataHookForMongod>(); });
 }
 }
diff --git a/src/mongo/s/SConscript b/src/mongo/s/SConscript
index 62105849406..f3d165806a0 100644
--- a/src/mongo/s/SConscript
+++ b/src/mongo/s/SConscript
@@ -17,7 +17,6 @@ env.Library(
     target='sharding_initialization',
     source=[
         'sharding_initialization.cpp',
-        'sharding_egress_metadata_hook_for_mongos.cpp',
     ],
     LIBDEPS=[
         '$BUILD_DIR/mongo/executor/network_interface_factory',
@@ -226,6 +225,7 @@ env.Library(
         'mongos_options.cpp',
         's_only.cpp',
         's_sharding_server_status.cpp',
+        'sharding_egress_metadata_hook_for_mongos.cpp',
         'version_mongos.cpp',
     ],
     LIBDEPS=[
@@ -260,7 +260,8 @@ env.Library(
     target='serveronly',
     source=[
         'd_sharding_server_status.cpp',
-        "d_state.cpp",
+        'd_state.cpp',
+        'sharding_egress_metadata_hook_for_mongod.cpp',
     ],
     LIBDEPS=[
         "coreshard",
diff --git a/src/mongo/s/client/shard_registry.cpp b/src/mongo/s/client/shard_registry.cpp
index db556719c31..232b4f1a446 100644
--- a/src/mongo/s/client/shard_registry.cpp
+++ b/src/mongo/s/client/shard_registry.cpp
@@ -244,7 +244,6 @@ void ShardRegistryData::addConfigShard(std::shared_ptr<Shard> shard) {
     _addShard_inlock(shard);
 }
 
-
 shared_ptr<Shard> ShardRegistryData::findByRSName(const string& name) const {
     stdx::lock_guard<stdx::mutex> lk(_mutex);
     auto i = _rsLookup.find(name);
diff --git a/src/mongo/s/grid.cpp b/src/mongo/s/grid.cpp
index 57538b1f6bb..e69e296e6cc 100644
--- a/src/mongo/s/grid.cpp
+++ b/src/mongo/s/grid.cpp
@@ -32,6 +32,7 @@
 
 #include "mongo/s/grid.h"
 
+#include "mongo/db/server_options.h"
 #include "mongo/executor/task_executor.h"
 #include "mongo/executor/task_executor_pool.h"
 #include "mongo/s/balancer/balancer_configuration.h"
@@ -89,11 +90,15 @@ void Grid::setAllowLocalHost(bool allow) {
 }
 
 repl::OpTime Grid::configOpTime() const {
+    invariant(serverGlobalParams.clusterRole != ClusterRole::ConfigServer);
+
     stdx::lock_guard<stdx::mutex> lk(_mutex);
     return _configOpTime;
 }
 
 void Grid::advanceConfigOpTime(repl::OpTime opTime) {
+    invariant(serverGlobalParams.clusterRole != ClusterRole::ConfigServer);
+
     stdx::lock_guard<stdx::mutex> lk(_mutex);
     if (_configOpTime < opTime) {
         _configOpTime = opTime;
diff --git a/src/mongo/s/grid.h b/src/mongo/s/grid.h
index 4316bca0f0d..02d5798d80d 100644
--- a/src/mongo/s/grid.h
+++ b/src/mongo/s/grid.h
@@ -122,8 +122,18 @@ public:
         return _balancerConfig.get();
     }
 
+    /**
+     * Returns the the last optime that a shard or config server has reported as the current
+     * committed optime on the config server.
+     * NOTE: This is not valid to call on a config server instance.
+     */
     repl::OpTime configOpTime() const;
 
+    /**
+     * Called whenever a mongos or shard gets a response from a config server or shard and updates
+     * what we've seen as the last config server optime.
+     * NOTE: This is not valid to call on a config server instance.
+     */
     void advanceConfigOpTime(repl::OpTime opTime);
 
     /**
@@ -156,6 +166,7 @@ private:
     mutable stdx::mutex _mutex;
 
     // Last known highest opTime from the config server that should be used when doing reads.
+    // This value is updated any time a shard or mongos talks to a config server or a shard.
     repl::OpTime _configOpTime;
 
     // Deprecated. This is only used on mongos, and once addShard is solely handled by the configs,
diff --git a/src/mongo/s/server.cpp b/src/mongo/s/server.cpp
index 809e9354116..a6755a82082 100644
--- a/src/mongo/s/server.cpp
+++ b/src/mongo/s/server.cpp
@@ -78,6 +78,7 @@
 #include "mongo/s/grid.h"
 #include "mongo/s/mongos_options.h"
 #include "mongo/s/query/cluster_cursor_cleanup_job.h"
+#include "mongo/s/sharding_egress_metadata_hook_for_mongos.h"
 #include "mongo/s/sharding_initialization.h"
 #include "mongo/s/version_mongos.h"
 #include "mongo/s/query/cluster_cursor_manager.h"
@@ -298,10 +299,11 @@ static Status initializeSharding(OperationContext* txn) {
     auto shardFactory =
         stdx::make_unique<ShardFactory>(std::move(buildersMap), std::move(targeterFactory));
 
-    Status status = initializeGlobalShardingState(mongosGlobalParams.configdbs,
-                                                  mongosGlobalParams.maxChunkSizeBytes,
-                                                  std::move(shardFactory),
-                                                  true);
+    Status status = initializeGlobalShardingState(
+        mongosGlobalParams.configdbs,
+        mongosGlobalParams.maxChunkSizeBytes,
+        std::move(shardFactory),
+        []() { return stdx::make_unique<rpc::ShardingEgressMetadataHookForMongos>(); });
 
     if (!status.isOK()) {
         return status;
diff --git a/src/mongo/s/sharding_egress_metadata_hook.cpp b/src/mongo/s/sharding_egress_metadata_hook.cpp
index 2e1b6793346..2040955f605 100644
--- a/src/mongo/s/sharding_egress_metadata_hook.cpp
+++ b/src/mongo/s/sharding_egress_metadata_hook.cpp
@@ -57,7 +57,7 @@ Status ShardingEgressMetadataHook::writeRequestMetadata(bool shardedConnection,
         if (!shardedConnection) {
             return Status::OK();
         }
-        rpc::ConfigServerMetadata(grid.configOpTime()).writeToMetadata(metadataBob);
+        rpc::ConfigServerMetadata(_getConfigServerOpTime()).writeToMetadata(metadataBob);
         return Status::OK();
     } catch (...) {
         return exceptionToStatus();
@@ -68,7 +68,7 @@ Status ShardingEgressMetadataHook::writeRequestMetadata(const HostAndPort& targe
                                                         BSONObjBuilder* metadataBob) {
     try {
         audit::writeImpersonatedUsersToMetadata(metadataBob);
-        rpc::ConfigServerMetadata(grid.configOpTime()).writeToMetadata(metadataBob);
+        rpc::ConfigServerMetadata(_getConfigServerOpTime()).writeToMetadata(metadataBob);
         return Status::OK();
     } catch (...) {
         return exceptionToStatus();
@@ -135,7 +135,5 @@ Status ShardingEgressMetadataHook::_advanceConfigOptimeFromShard(ShardId shardId
     }
 }
 
-void ShardingEgressMetadataHook::_saveGLEStats(const BSONObj& metadata, StringData hostString) {}
-
 }  // namespace rpc
 }  // namespace mongo
diff --git a/src/mongo/s/sharding_egress_metadata_hook.h b/src/mongo/s/sharding_egress_metadata_hook.h
index 06fe41b1ebe..c510aefaab4 100644
--- a/src/mongo/s/sharding_egress_metadata_hook.h
+++ b/src/mongo/s/sharding_egress_metadata_hook.h
@@ -31,6 +31,7 @@
 #include <memory>
 
 #include "mongo/base/string_data.h"
+#include "mongo/db/repl/optime.h"
 #include "mongo/rpc/metadata/metadata_hook.h"
 #include "mongo/s/client/shard.h"
 
@@ -42,6 +43,8 @@ namespace rpc {
 
 class ShardingEgressMetadataHook : public rpc::EgressMetadataHook {
 public:
+    virtual ~ShardingEgressMetadataHook() = default;
+
     Status readReplyMetadata(const HostAndPort& replySource, const BSONObj& metadataObj) override;
     Status writeRequestMetadata(const HostAndPort& target, BSONObjBuilder* metadataBob) override;
 
@@ -55,10 +58,28 @@ public:
                                 const StringData target,
                                 BSONObjBuilder* metadataBob);
 
-private:
-    virtual void _saveGLEStats(const BSONObj& metadata, StringData hostString);
+protected:
+    /**
+     * On mongod this is a no-op.
+     * On mongos it looks for $gleStats in a command's reply metadata, and fills in the
+     * ClusterLastErrorInfo for this thread's associated Client with the data, if found.
+     * This data will be used by subsequent GLE calls, to ensure we look for the correct write on
+     * the correct PRIMARY.
+     */
+    virtual void _saveGLEStats(const BSONObj& metadata, StringData hostString) = 0;
+
+    /**
+     * Called by writeRequestMetadata() to find the config server optime that should be sent as part
+     * of the ConfigServerMetadata.
+     */
+    virtual repl::OpTime _getConfigServerOpTime() = 0;
 
-    Status _advanceConfigOptimeFromShard(ShardId shardId, const BSONObj& metadataObj);
+    /**
+     * On config servers this is a no-op.
+     * On shards and mongoses this advances the Grid's stored config server optime based on the
+     * metadata in the response object from running a command.
+     */
+    virtual Status _advanceConfigOptimeFromShard(ShardId shardId, const BSONObj& metadataObj);
 };
 
 }  // namespace rpc
diff --git a/src/mongo/s/sharding_egress_metadata_hook_for_mongod.cpp b/src/mongo/s/sharding_egress_metadata_hook_for_mongod.cpp
new file mode 100644
index 00000000000..2c8dc215847
--- /dev/null
+++ b/src/mongo/s/sharding_egress_metadata_hook_for_mongod.cpp
@@ -0,0 +1,67 @@
+/**
+ *    Copyright (C) 2016 MongoDB Inc.
+ *
+ *    This program is free software: you can redistribute it and/or  modify
+ *    it under the terms of the GNU Affero General Public License, version 3,
+ *    as published by the Free Software Foundation.
+ *
+ *    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
+ *    GNU Affero General Public License for more details.
+ *
+ *    You should have received a copy of the GNU Affero General Public License
+ *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ *    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 GNU Affero General 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.
+ */
+
+#define MONGO_LOG_DEFAULT_COMPONENT ::mongo::logger::LogComponent::kSharding
+
+#include "mongo/platform/basic.h"
+
+#include "mongo/s/sharding_egress_metadata_hook_for_mongod.h"
+
+#include "mongo/base/status.h"
+#include "mongo/db/repl/replication_coordinator_global.h"
+#include "mongo/db/server_options.h"
+#include "mongo/s/grid.h"
+#include "mongo/s/sharding_egress_metadata_hook_for_mongos.h"
+
+namespace mongo {
+
+namespace rpc {
+
+void ShardingEgressMetadataHookForMongod::_saveGLEStats(const BSONObj& metadata,
+                                                        StringData hostString) {}
+
+repl::OpTime ShardingEgressMetadataHookForMongod::_getConfigServerOpTime() {
+    if (serverGlobalParams.clusterRole == ClusterRole::ConfigServer) {
+        return repl::getGlobalReplicationCoordinator()->getCurrentCommittedSnapshotOpTime();
+    } else {
+        // TODO uncomment as part of SERVER-22663
+        // invariant(serverGlobalParams.clusterRole == ClusterRole::ShardServer);
+        return grid.configOpTime();
+    }
+}
+
+Status ShardingEgressMetadataHookForMongod::_advanceConfigOptimeFromShard(
+    ShardId shardId, const BSONObj& metadataObj) {
+    if (serverGlobalParams.clusterRole == ClusterRole::ConfigServer) {
+        return Status::OK();
+    }
+    return ShardingEgressMetadataHook::_advanceConfigOptimeFromShard(shardId, metadataObj);
+}
+
+}  // namespace rpc
+}  // namespace mongo
diff --git a/src/mongo/s/sharding_egress_metadata_hook_for_mongod.h b/src/mongo/s/sharding_egress_metadata_hook_for_mongod.h
new file mode 100644
index 00000000000..56272d97cd2
--- /dev/null
+++ b/src/mongo/s/sharding_egress_metadata_hook_for_mongod.h
@@ -0,0 +1,48 @@
+/**
+ *    Copyright (C) 2016 MongoDB Inc.
+ *
+ *    This program is free software: you can redistribute it and/or  modify
+ *    it under the terms of the GNU Affero General Public License, version 3,
+ *    as published by the Free Software Foundation.
+ *
+ *    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
+ *    GNU Affero General Public License for more details.
+ *
+ *    You should have received a copy of the GNU Affero General Public License
+ *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ *    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 GNU Affero General 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/s/sharding_egress_metadata_hook.h"
+
+namespace mongo {
+
+namespace rpc {
+
+class ShardingEgressMetadataHookForMongod final : public ShardingEgressMetadataHook {
+public:
+    ShardingEgressMetadataHookForMongod() = default;
+
+private:
+    void _saveGLEStats(const BSONObj& metadata, StringData hostString) override;
+    repl::OpTime _getConfigServerOpTime() override;
+    Status _advanceConfigOptimeFromShard(ShardId shardId, const BSONObj& metadataObj) override;
+};
+
+}  // namespace rpc
+}  // namespace mongo
diff --git a/src/mongo/s/sharding_egress_metadata_hook_for_mongos.cpp b/src/mongo/s/sharding_egress_metadata_hook_for_mongos.cpp
index ab74ecf35d7..466d9306de9 100644
--- a/src/mongo/s/sharding_egress_metadata_hook_for_mongos.cpp
+++ b/src/mongo/s/sharding_egress_metadata_hook_for_mongos.cpp
@@ -30,10 +30,12 @@
 
 #include "mongo/platform/basic.h"
 
+#include "mongo/s/sharding_egress_metadata_hook_for_mongos.h"
+
 #include "mongo/db/client.h"
 #include "mongo/rpc/metadata/sharding_metadata.h"
 #include "mongo/s/cluster_last_error_info.h"
-#include "mongo/s/sharding_egress_metadata_hook_for_mongos.h"
+#include "mongo/s/grid.h"
 #include "mongo/util/log.h"
 
 namespace mongo {
@@ -76,5 +78,9 @@ void ShardingEgressMetadataHookForMongos::_saveGLEStats(const BSONObj& metadata,
             HostOpTime(shardingMetadata.getLastOpTime(), shardingMetadata.getLastElectionId()));
 }
 
+repl::OpTime ShardingEgressMetadataHookForMongos::_getConfigServerOpTime() {
+    return grid.configOpTime();
+}
+
 }  // namespace rpc
 }  // namespace mongo
diff --git a/src/mongo/s/sharding_egress_metadata_hook_for_mongos.h b/src/mongo/s/sharding_egress_metadata_hook_for_mongos.h
index 11a753e7506..92fd9cf9eef 100644
--- a/src/mongo/s/sharding_egress_metadata_hook_for_mongos.h
+++ b/src/mongo/s/sharding_egress_metadata_hook_for_mongos.h
@@ -36,14 +36,8 @@ namespace rpc {
 
 class ShardingEgressMetadataHookForMongos final : public ShardingEgressMetadataHook {
 private:
-    /**
-     * Looks for $gleStats in a command's reply metadata, and fills in the ClusterLastErrorInfo for
-     * this thread's associated Client with the data, if found. This data will be used by subsequent
-     * GLE calls, to ensure we look for the correct write on the correct PRIMARY.
-     *
-     * Returns the result from calling runCommand
-     */
     void _saveGLEStats(const BSONObj& metadata, StringData hostString) override;
+    repl::OpTime _getConfigServerOpTime() override;
 };
 
 }  // namespace rpc
diff --git a/src/mongo/s/sharding_initialization.cpp b/src/mongo/s/sharding_initialization.cpp
index d3019a5ae61..b66a7571a9e 100644
--- a/src/mongo/s/sharding_initialization.cpp
+++ b/src/mongo/s/sharding_initialization.cpp
@@ -51,13 +51,12 @@
 #include "mongo/s/client/shard_registry.h"
 #include "mongo/s/client/sharding_network_connection_hook.h"
 #include "mongo/s/grid.h"
-#include "mongo/s/sharding_egress_metadata_hook.h"
-#include "mongo/s/sharding_egress_metadata_hook_for_mongos.h"
 #include "mongo/s/catalog/catalog_cache.h"
 #include "mongo/s/catalog/replset/catalog_manager_replica_set.h"
 #include "mongo/s/catalog/replset/dist_lock_catalog_impl.h"
 #include "mongo/s/catalog/replset/replset_dist_lock_manager.h"
 #include "mongo/s/query/cluster_cursor_manager.h"
+#include "mongo/s/sharding_egress_metadata_hook.h"
 #include "mongo/stdx/memory.h"
 #include "mongo/util/exit.h"
 #include "mongo/util/log.h"
@@ -101,16 +100,11 @@ std::unique_ptr<CatalogManager> makeCatalogManager(ServiceContext* service,
             executor::makeNetworkInterface("NetworkInterfaceASIO-AddShard-TaskExecutor")));
 }
 
-std::unique_ptr<TaskExecutorPool> makeTaskExecutorPool(std::unique_ptr<NetworkInterface> fixedNet,
-                                                       bool isMongos) {
+std::unique_ptr<TaskExecutorPool> makeTaskExecutorPool(
+    std::unique_ptr<NetworkInterface> fixedNet,
+    std::unique_ptr<rpc::EgressMetadataHook> metadataHook) {
     std::vector<std::unique_ptr<executor::TaskExecutor>> executors;
     for (size_t i = 0; i < TaskExecutorPool::getSuggestedPoolSize(); ++i) {
-        std::unique_ptr<rpc::EgressMetadataHook> metadataHook;
-        if (isMongos) {
-            metadataHook = stdx::make_unique<rpc::ShardingEgressMetadataHookForMongos>();
-        } else {
-            metadataHook = stdx::make_unique<rpc::ShardingEgressMetadataHook>();
-        };
         auto net = executor::makeNetworkInterface(
             "NetworkInterfaceASIO-TaskExecutorPool-" + std::to_string(i),
             stdx::make_unique<ShardingNetworkConnectionHook>(),
@@ -137,24 +131,17 @@ std::unique_ptr<TaskExecutorPool> makeTaskExecutorPool(std::unique_ptr<NetworkIn
 Status initializeGlobalShardingState(const ConnectionString& configCS,
                                      uint64_t maxChunkSizeBytes,
                                      std::unique_ptr<ShardFactory> shardFactory,
-                                     bool isMongos) {
+                                     rpc::ShardingEgressMetadataHookBuilder hookBuilder) {
     if (configCS.type() == ConnectionString::INVALID) {
         return {ErrorCodes::BadValue, "Unrecognized connection string."};
     }
 
-    std::unique_ptr<rpc::EgressMetadataHook> metadataHook;
-    if (isMongos) {
-        metadataHook = stdx::make_unique<rpc::ShardingEgressMetadataHookForMongos>();
-    } else {
-        metadataHook = stdx::make_unique<rpc::ShardingEgressMetadataHook>();
-    }
-
     auto network =
         executor::makeNetworkInterface("NetworkInterfaceASIO-ShardRegistry",
                                        stdx::make_unique<ShardingNetworkConnectionHook>(),
-                                       std::move(metadataHook));
+                                       hookBuilder());
     auto networkPtr = network.get();
-    auto executorPool = makeTaskExecutorPool(std::move(network), isMongos);
+    auto executorPool = makeTaskExecutorPool(std::move(network), hookBuilder());
     executorPool->startup();
 
     auto shardRegistry(stdx::make_unique<ShardRegistry>(std::move(shardFactory), configCS));
diff --git a/src/mongo/s/sharding_initialization.h b/src/mongo/s/sharding_initialization.h
index a4508870088..d31aabf261d 100644
--- a/src/mongo/s/sharding_initialization.h
+++ b/src/mongo/s/sharding_initialization.h
@@ -31,6 +31,8 @@
 #include <cstdint>
 #include <memory>
 
+#include "mongo/stdx/functional.h"
+
 namespace mongo {
 
 class ConnectionString;
@@ -38,6 +40,12 @@ class OperationContext;
 class ShardFactory;
 class Status;
 
+namespace rpc {
+class ShardingEgressMetadataHook;
+using ShardingEgressMetadataHookBuilder =
+    stdx::function<std::unique_ptr<ShardingEgressMetadataHook>()>;
+}  // namespace rpc
+
 /**
  * Takes in the connection string for reaching the config servers and initializes the global
  * CatalogManager, ShardingRegistry, and grid objects.
@@ -45,7 +53,8 @@ class Status;
 Status initializeGlobalShardingState(const ConnectionString& configCS,
                                      uint64_t maxChunkSizeBytes,
                                      std::unique_ptr<ShardFactory> shardFactory,
-                                     bool isMongos);
+                                     rpc::ShardingEgressMetadataHookBuilder hookBuilder);
+
 /**
  * Tries to contact the config server and reload the shard registry until it succeeds or
  * is interrupted.
diff --git a/src/mongo/s/sharding_test_fixture.cpp b/src/mongo/s/sharding_test_fixture.cpp
index d2287936993..86921c8c75b 100644
--- a/src/mongo/s/sharding_test_fixture.cpp
+++ b/src/mongo/s/sharding_test_fixture.cpp
@@ -60,7 +60,7 @@
 #include "mongo/s/grid.h"
 #include "mongo/s/query/cluster_cursor_manager.h"
 #include "mongo/s/set_shard_version_request.h"
-#include "mongo/s/sharding_egress_metadata_hook.h"
+#include "mongo/s/sharding_egress_metadata_hook_for_mongos.h"
 #include "mongo/s/write_ops/batched_command_request.h"
 #include "mongo/s/write_ops/batched_command_response.h"
 #include "mongo/stdx/memory.h"
@@ -72,7 +72,7 @@ using executor::NetworkInterfaceMock;
 using executor::NetworkTestEnv;
 using executor::RemoteCommandRequest;
 using executor::RemoteCommandResponse;
-using rpc::ShardingEgressMetadataHook;
+using rpc::ShardingEgressMetadataHookForMongos;
 using unittest::assertGet;
 
 using std::string;
@@ -95,14 +95,14 @@ void ShardingTestFixture::setUp() {
 
     // Set up executor pool used for most operations.
     auto fixedNet = stdx::make_unique<executor::NetworkInterfaceMock>();
-    fixedNet->setEgressMetadataHook(stdx::make_unique<ShardingEgressMetadataHook>());
+    fixedNet->setEgressMetadataHook(stdx::make_unique<ShardingEgressMetadataHookForMongos>());
     _mockNetwork = fixedNet.get();
     auto fixedExec = makeThreadPoolTestExecutor(std::move(fixedNet));
     _networkTestEnv = stdx::make_unique<NetworkTestEnv>(fixedExec.get(), _mockNetwork);
     _executor = fixedExec.get();
 
     auto netForPool = stdx::make_unique<executor::NetworkInterfaceMock>();
-    netForPool->setEgressMetadataHook(stdx::make_unique<ShardingEgressMetadataHook>());
+    netForPool->setEgressMetadataHook(stdx::make_unique<ShardingEgressMetadataHookForMongos>());
     auto execForPool = makeThreadPoolTestExecutor(std::move(netForPool));
     std::vector<std::unique_ptr<executor::TaskExecutor>> executorsForPool;
     executorsForPool.emplace_back(std::move(execForPool));