SERVER-127233 Introduce stub recipient fetch final collection stats command (#54169)

GitOrigin-RevId: 561091dad4bcd568209fd3a52b68ab0a005971b2

jstests/auth/internal_command_auth_validation.js

@@ -707,6 +707,13 @@ const internalCommandsMap = {
             reshardingUUID: UUID(),
         },
     },
+    _shardsvrReshardingRecipientFetchFinalCollectionStats: {
+        testname: "_shardsvrReshardingRecipientFetchFinalCollectionStats",
+        command: {
+            _shardsvrReshardingRecipientFetchFinalCollectionStats: "test.x",
+            reshardingUUID: UUID(),
+        },
+    },
     _shardsvrReshardingDonorStartChangeStreamsMonitor: {
         testname: "_shardsvrReshardingDonorStartChangeStreamsMonitor",
         command: {

jstests/core/catalog/views/views_all_commands.js

@@ -209,6 +209,7 @@ let viewsCommandTests = {
     _shardsvrRenameIndexMetadata: {skip: isAnInternalCommand},
     _shardsvrReshardCollection: {skip: isAnInternalCommand},
     _shardsvrReshardingDonorFetchFinalCollectionStats: {skip: isAnInternalCommand},
+    _shardsvrReshardingRecipientFetchFinalCollectionStats: {skip: isAnInternalCommand},
     _shardsvrReshardingDonorStartChangeStreamsMonitor: {skip: isAnInternalCommand},
     _shardsvrReshardingOperationTime: {skip: isAnInternalCommand},
     _shardsvrReshardDonorInitialize: {skip: isAnInternalCommand},

jstests/libs/write_concern_all_commands.js

@@ -197,6 +197,7 @@ const wcCommandsTests = {
     _shardsvrRenameIndexMetadata: {skip: "internal command"},
     _shardsvrReshardCollection: {skip: "internal command"},
     _shardsvrReshardingDonorFetchFinalCollectionStats: {skip: "internal command"},
+    _shardsvrReshardingRecipientFetchFinalCollectionStats: {skip: "internal command"},
     _shardsvrReshardingDonorStartChangeStreamsMonitor: {skip: "internal command"},
     _shardsvrReshardingOperationTime: {skip: "internal command"},
     _shardsvrReshardDonorInitialize: {skip: "internal command"},
@@ -3425,6 +3426,7 @@ const wcTimeseriesCommandsTests = {
     _shardsvrRenameIndexMetadata: {skip: "internal command"},
     _shardsvrReshardCollection: {skip: "internal command"},
     _shardsvrReshardingDonorFetchFinalCollectionStats: {skip: "internal command"},
+    _shardsvrReshardingRecipientFetchFinalCollectionStats: {skip: "internal command"},
     _shardsvrReshardingDonorStartChangeStreamsMonitor: {skip: "internal command"},
     _shardsvrReshardingOperationTime: {skip: "internal command"},
     _shardsvrReshardDonorInitialize: {skip: "internal command"},

jstests/replsets/all_commands_downgrading_to_upgraded.js

@@ -143,6 +143,7 @@ const allCommands = {
     _shardsvrDropDatabaseParticipant: {skip: isAnInternalCommand},
     _shardsvrReshardCollection: {skip: isAnInternalCommand},
     _shardsvrReshardingDonorFetchFinalCollectionStats: {skip: isAnInternalCommand},
+    _shardsvrReshardingRecipientFetchFinalCollectionStats: {skip: isAnInternalCommand},
     _shardsvrReshardingDonorStartChangeStreamsMonitor: {skip: isAnInternalCommand},
     _shardsvrReshardingOperationTime: {skip: isAnInternalCommand},
     _shardsvrReshardDonorInitialize: {skip: isAnInternalCommand},

jstests/replsets/db_reads_while_recovering_all_commands.js

@@ -158,6 +158,7 @@ const allCommands = {
     _shardsvrBeginMigrationBlockingOperation: {skip: isAnInternalCommand},
     _shardsvrEndMigrationBlockingOperation: {skip: isAnInternalCommand},
     _shardsvrReshardingDonorFetchFinalCollectionStats: {skip: isAnInternalCommand},
+    _shardsvrReshardingRecipientFetchFinalCollectionStats: {skip: isAnInternalCommand},
     _shardsvrReshardingDonorStartChangeStreamsMonitor: {skip: isAnInternalCommand},
     _shardsvrUpgradeDowngradeViewlessTimeseries: {skip: isAnInternalCommand},
     _shardsvrTimeseriesUpgradeDowngradePrepare: {skip: isAnInternalCommand},

jstests/sharding/all_commands_direct_shard_connection_auth.js

@@ -131,6 +131,7 @@ const allCommands = {
     _shardsvrRenameCollectionParticipantUnblock: {skip: isAnInternalCommand},
     _shardsvrRenameIndexMetadata: {skip: isAnInternalCommand},
     _shardsvrReshardingDonorFetchFinalCollectionStats: {skip: isAnInternalCommand},
+    _shardsvrReshardingRecipientFetchFinalCollectionStats: {skip: isAnInternalCommand},
     _shardsvrReshardingDonorStartChangeStreamsMonitor: {skip: isAnInternalCommand},
     _shardsvrResolveView: {skip: isAnInternalCommand},
     _shardsvrRunSearchIndexCommand: {skip: isAnInternalCommand},

jstests/sharding/database_versioning_all_commands.js

@@ -1188,6 +1188,7 @@ const allTestCases = {
             },
         },
         _shardsvrReshardingDonorFetchFinalCollectionStats: {skip: "TODO"},
+        _shardsvrReshardingRecipientFetchFinalCollectionStats: {skip: "TODO"},
         _shardsvrReshardingDonorStartChangeStreamsMonitor: {skip: "TODO"},
         _shardsvrReshardingOperationTime: {skip: "TODO"},
         _shardsvrResolveView: {

jstests/sharding/libs/last_lts_mongod_commands.js

@@ -49,6 +49,7 @@ export const commandsAddedToMongodSinceLastLTS = [
     "_flushShardRegistry",
     "releaseMemory",
     "_shardsvrReshardingDonorFetchFinalCollectionStats",
+    "_shardsvrReshardingRecipientFetchFinalCollectionStats",
     "_shardsvrReshardingDonorStartChangeStreamsMonitor",
     "startTrafficRecording",
     "stopTrafficRecording",

jstests/sharding/read_write_concern_defaults_application.js

@@ -199,6 +199,7 @@ let testCases = {
     _shardsvrRenameIndexMetadata: {skip: "internal command"},
     _shardsvrReshardCollection: {skip: "internal command"},
     _shardsvrReshardingDonorFetchFinalCollectionStats: {skip: "internal command"},
+    _shardsvrReshardingRecipientFetchFinalCollectionStats: {skip: "internal command"},
     _shardsvrReshardingDonorStartChangeStreamsMonitor: {skip: "internal command"},
     _shardsvrReshardingOperationTime: {skip: "internal command"},
     _shardsvrReshardDonorInitialize: {skip: "internal command"},

src/mongo/db/s/BUILD.bazel

@@ -564,6 +564,7 @@ mongo_cc_library(
         "shardsvr_resharding_donor_fetch_final_collection_stats_command.cpp",
         "shardsvr_resharding_donor_start_change_streams_monitor_command.cpp",
         "shardsvr_resharding_operation_time_command.cpp",
+        "shardsvr_resharding_recipient_fetch_final_collection_stats_command.cpp",
         "split_vector_command.cpp",
         "txn_two_phase_commit_cmds.cpp",
         ":resharding_test_commands_gen",

src/mongo/db/s/resharding/shardsvr_resharding_commands.idl

@@ -46,6 +46,15 @@ structs:
                 type: safeInt64
                 description: "The change in the number of documents since the provided cloneTimestamp."
 
+    ShardsvrReshardingRecipientFetchFinalCollectionStatsResponse:
+        description: "Response for the _shardsvrReshardingRecipientFetchFinalCollectionStats command."
+        is_command_reply: true
+        strict: false
+        fields:
+            documentsDelta:
+                type: safeInt64
+                description: "The change in the number of documents during the applying phase."
+
 commands:
     _shardsvrReshardDonorInitialize:
         description:
@@ -101,6 +110,22 @@ commands:
                 type: uuid
                 description: "The UUID for the resharding operation."
 
+    _shardsvrReshardingRecipientFetchFinalCollectionStats:
+        command_name: _shardsvrReshardingRecipientFetchFinalCollectionStats
+        cpp_name: ShardsvrReshardingRecipientFetchFinalCollectionStats
+        description:
+            "The internal command for querying a resharding recipient shard for the changes in
+            the number of documents in the collection being resharded during the applying phase."
+        namespace: type
+        type: namespacestring
+        reply_type: ShardsvrReshardingRecipientFetchFinalCollectionStatsResponse
+        api_version: ""
+        strict: false
+        fields:
+            reshardingUUID:
+                type: uuid
+                description: "The UUID for the resharding operation."
+
     _shardsvrReshardRecipientInitialize:
         description:
             "The internal command sent by the coordinator to recipient shards to

src/mongo/db/s/shardsvr_resharding_recipient_fetch_final_collection_stats_command.cpp

@@ -0,0 +1,127 @@
+/**
+ *    Copyright (C) 2026-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.
+ */
+
+#include "mongo/base/error_codes.h"
+#include "mongo/db/auth/action_type.h"
+#include "mongo/db/auth/authorization_session.h"
+#include "mongo/db/auth/resource_pattern.h"
+#include "mongo/db/commands.h"
+#include "mongo/db/namespace_string.h"
+#include "mongo/db/operation_context.h"
+#include "mongo/db/s/resharding/resharding_donor_recipient_common.h"
+#include "mongo/db/s/resharding/resharding_recipient_service.h"
+#include "mongo/db/s/resharding/shardsvr_resharding_commands_gen.h"
+#include "mongo/db/service_context.h"
+#include "mongo/logv2/log.h"
+#include "mongo/s/resharding/resharding_feature_flag_gen.h"
+#include "mongo/util/assert_util.h"
+
+#include <string>
+
+#include <boost/move/utility_core.hpp>
+
+
+#define MONGO_LOGV2_DEFAULT_COMPONENT ::mongo::logv2::LogComponent::kCommand
+
+namespace mongo {
+
+namespace {
+
+class ShardsvrReshardingRecipientFetchFinalCollectionStatsCommand
+    : public TypedCommand<ShardsvrReshardingRecipientFetchFinalCollectionStatsCommand> {
+public:
+    using Request = ShardsvrReshardingRecipientFetchFinalCollectionStats;
+    using Response = ShardsvrReshardingRecipientFetchFinalCollectionStatsResponse;
+
+    AllowedOnSecondary secondaryAllowed(ServiceContext*) const override {
+        return AllowedOnSecondary::kNever;
+    }
+
+    bool adminOnly() const override {
+        return true;
+    }
+
+    std::string help() const override {
+        return "Internal command for querying a resharding recipient shard for the change in the "
+               "number of documents in the collection being resharded during the applying phase.";
+    }
+
+    class Invocation final : public InvocationBase {
+    public:
+        using InvocationBase::InvocationBase;
+
+        Response typedRun(OperationContext* opCtx) {
+            opCtx->setAlwaysInterruptAtStepDownOrUp_UNSAFE();
+
+            uassert(ErrorCodes::IllegalOperation,
+                    "_shardsvrReshardingRecipientFetchFinalCollectionStats is only supported on "
+                    "shardsvr mongod",
+                    serverGlobalParams.clusterRole.has(ClusterRole::ShardServer));
+
+            auto recipientMachine = resharding::tryGetReshardingStateMachineAndThrowIfShuttingDown<
+                ReshardingRecipientService,
+                ReshardingRecipientService::RecipientStateMachine,
+                ReshardingRecipientDocument>(opCtx, request().getReshardingUUID());
+
+            uassert(12723301,
+                    str::stream() << "No resharding operation in progress with uuid "
+                                  << request().getReshardingUUID(),
+                    recipientMachine);
+
+            uasserted(ErrorCodes::NotImplemented,
+                      "_shardsvrReshardingRecipientFetchFinalCollectionStats is not yet "
+                      "implemented");
+        }
+
+    private:
+        NamespaceString ns() const override {
+            return request().getCommandParameter();
+        }
+
+        bool supportsWriteConcern() const override {
+            return false;
+        }
+
+        void doCheckAuthorization(OperationContext* opCtx) const override {
+            uassert(ErrorCodes::Unauthorized,
+                    "Unauthorized",
+                    AuthorizationSession::get(opCtx->getClient())
+                        ->isAuthorizedForActionsOnResource(
+                            ResourcePattern::forClusterResource(request().getDbName().tenantId()),
+                            ActionType::internal));
+        }
+    };
+};
+
+MONGO_REGISTER_COMMAND(ShardsvrReshardingRecipientFetchFinalCollectionStatsCommand)
+    .requiresFeatureFlag(resharding::gFeatureFlagReshardingVerification)
+    .forShard();
+
+}  // namespace
+}  // namespace mongo