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/**
* Copyright (C) 2019-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.
*/
#define MONGO_LOG_DEFAULT_COMPONENT ::mongo::logger::LogComponent::kSharding
#include "mongo/platform/basic.h"
#include "mongo/db/s/migration_util.h"
#include "mongo/base/error_codes.h"
#include "mongo/bson/bsonobj.h"
#include "mongo/bson/bsonobjbuilder.h"
#include "mongo/client/query.h"
#include "mongo/db/catalog/collection_catalog_helper.h"
#include "mongo/db/catalog_raii.h"
#include "mongo/db/dbdirectclient.h"
#include "mongo/db/logical_session_cache.h"
#include "mongo/db/namespace_string.h"
#include "mongo/db/ops/write_ops.h"
#include "mongo/db/repl/repl_client_info.h"
#include "mongo/db/s/active_migrations_registry.h"
#include "mongo/db/s/collection_sharding_runtime.h"
#include "mongo/db/s/migration_coordinator.h"
#include "mongo/db/s/shard_filtering_metadata_refresh.h"
#include "mongo/db/write_concern.h"
#include "mongo/executor/task_executor_pool.h"
#include "mongo/executor/thread_pool_task_executor.h"
#include "mongo/rpc/get_status_from_command_result.h"
#include "mongo/s/catalog/type_chunk.h"
#include "mongo/s/client/shard.h"
#include "mongo/s/grid.h"
#include "mongo/s/request_types/ensure_chunk_version_is_greater_than_gen.h"
#include "mongo/util/exit.h"
#include "mongo/util/log.h"
namespace mongo {
namespace migrationutil {
namespace {
const char kSourceShard[] = "source";
const char kDestinationShard[] = "destination";
const char kIsDonorShard[] = "isDonorShard";
const char kChunk[] = "chunk";
const char kCollection[] = "collection";
const WriteConcernOptions kMajorityWriteConcern(WriteConcernOptions::kMajority,
WriteConcernOptions::SyncMode::UNSET,
WriteConcernOptions::kNoTimeout);
template <typename Cmd>
void sendToRecipient(OperationContext* opCtx, const ShardId& recipientId, const Cmd& cmd) {
auto recipientShard =
uassertStatusOK(Grid::get(opCtx)->shardRegistry()->getShard(opCtx, recipientId));
LOG(1) << "Sending request " << cmd.toBSON({}) << " to recipient.";
auto response = recipientShard->runCommandWithFixedRetryAttempts(
opCtx,
ReadPreferenceSetting{ReadPreference::PrimaryOnly},
"config",
cmd.toBSON(BSON(WriteConcernOptions::kWriteConcernField << WriteConcernOptions::Majority)),
Shard::RetryPolicy::kIdempotent);
uassertStatusOK(Shard::CommandResponse::getEffectiveStatus(response));
}
} // namespace
BSONObj makeMigrationStatusDocument(const NamespaceString& nss,
const ShardId& fromShard,
const ShardId& toShard,
const bool& isDonorShard,
const BSONObj& min,
const BSONObj& max) {
BSONObjBuilder builder;
builder.append(kSourceShard, fromShard.toString());
builder.append(kDestinationShard, toShard.toString());
builder.append(kIsDonorShard, isDonorShard);
builder.append(kChunk, BSON(ChunkType::min(min) << ChunkType::max(max)));
builder.append(kCollection, nss.ns());
return builder.obj();
}
Query overlappingRangeQuery(const ChunkRange& range, const UUID& uuid) {
return QUERY(RangeDeletionTask::kCollectionUuidFieldName
<< uuid << RangeDeletionTask::kRangeFieldName + "." + ChunkRange::kMinKey << LT
<< range.getMax() << RangeDeletionTask::kRangeFieldName + "." + ChunkRange::kMaxKey
<< GT << range.getMin());
}
bool checkForConflictingDeletions(OperationContext* opCtx,
const ChunkRange& range,
const UUID& uuid) {
PersistentTaskStore<RangeDeletionTask> store(opCtx, NamespaceString::kRangeDeletionNamespace);
return store.count(opCtx, overlappingRangeQuery(range, uuid)) > 0;
}
ExecutorFuture<bool> submitRangeDeletionTask(OperationContext* opCtx,
const RangeDeletionTask& deletionTask) {
const auto serviceContext = opCtx->getServiceContext();
// TODO (SERVER-45577): Use the Grid's fixed executor once the refresh is done asynchronously.
// An arbitrary executor is being used temporarily because unit tests have only one thread in
// the fixed executor, and that thread is needed to respond to the refresh.
return ExecutorFuture<void>(
Grid::get(serviceContext)->getExecutorPool()->getArbitraryExecutor())
.then([=] {
ThreadClient tc(kRangeDeletionThreadName, serviceContext);
{
stdx::lock_guard<Client> lk(*tc.get());
tc->setSystemOperationKillable(lk);
}
auto uniqueOpCtx = tc->makeOperationContext();
auto opCtx = uniqueOpCtx.get();
boost::optional<AutoGetCollection> autoColl;
autoColl.emplace(opCtx, deletionTask.getNss(), MODE_IS);
auto css = CollectionShardingRuntime::get(opCtx, deletionTask.getNss());
if (!css->getCurrentMetadataIfKnown() ||
!css->getCurrentMetadata()->uuidMatches(deletionTask.getCollectionUuid())) {
// If the collection's filtering metadata is not known or its UUID does not match
// the UUID of the deletion task, force a filtering metadata refresh once, because
// this node may have just stepped up and therefore may have a stale cache.
LOG(0) << "Filtering metadata for namespace in deletion task "
<< deletionTask.toBSON()
<< (css->getCurrentMetadataIfKnown()
? " has UUID that does not match UUID of the deletion task"
: " is not known")
<< ", forcing a refresh of " << deletionTask.getNss();
// TODO (SERVER-45577): Add an asynchronous version of
// forceShardFilteringMetadataRefresh to avoid blocking on the network in the
// thread pool.
autoColl.reset();
forceShardFilteringMetadataRefresh(opCtx, deletionTask.getNss(), true);
}
autoColl.emplace(opCtx, deletionTask.getNss(), MODE_IS);
if (!css->getCurrentMetadataIfKnown() ||
!css->getCurrentMetadata()->uuidMatches(deletionTask.getCollectionUuid())) {
LOG(0) << "Even after forced refresh, filtering metadata for namespace in deletion "
"task "
<< deletionTask.toBSON()
<< (css->getCurrentMetadataIfKnown()
? "has UUID that does not match UUID of the deletion task"
: "is not known")
<< ", deleting the task.";
autoColl.reset();
deleteRangeDeletionTaskLocally(
opCtx, deletionTask.getId(), ShardingCatalogClient::kLocalWriteConcern);
return false;
}
LOG(0) << "Submitting range deletion task " << deletionTask.toBSON();
const auto whenToClean = deletionTask.getWhenToClean() == CleanWhenEnum::kNow
? CollectionShardingRuntime::kNow
: CollectionShardingRuntime::kDelayed;
auto cleanupCompleteFuture = css->cleanUpRange(deletionTask.getRange(), whenToClean);
if (cleanupCompleteFuture.isReady() &&
!cleanupCompleteFuture.getNoThrow(opCtx).isOK()) {
LOG(0) << "Failed to submit range deletion task " << deletionTask.toBSON()
<< causedBy(cleanupCompleteFuture.getNoThrow(opCtx));
return false;
}
return true;
});
}
void submitPendingDeletions(OperationContext* opCtx) {
PersistentTaskStore<RangeDeletionTask> store(opCtx, NamespaceString::kRangeDeletionNamespace);
auto query = QUERY("pending" << BSON("$exists" << false));
std::vector<RangeDeletionTask> invalidRanges;
store.forEach(opCtx, query, [&opCtx, &invalidRanges](const RangeDeletionTask& deletionTask) {
migrationutil::submitRangeDeletionTask(opCtx, deletionTask);
return true;
});
}
void resubmitRangeDeletionsOnStepUp(ServiceContext* serviceContext) {
LOG(0) << "Starting pending deletion submission thread.";
auto executor = Grid::get(serviceContext)->getExecutorPool()->getFixedExecutor();
ExecutorFuture<void>(executor).getAsync([serviceContext](const Status& status) {
ThreadClient tc("ResubmitRangeDeletions", serviceContext);
{
stdx::lock_guard<Client> lk(*tc.get());
tc->setSystemOperationKillable(lk);
}
auto opCtx = tc->makeOperationContext();
submitPendingDeletions(opCtx.get());
});
}
void dropRangeDeletionsCollection(OperationContext* opCtx) {
DBDirectClient client(opCtx);
client.dropCollection(NamespaceString::kRangeDeletionNamespace.toString(),
WriteConcerns::kMajorityWriteConcern);
}
template <typename Callable>
void forEachOrphanRange(OperationContext* opCtx, const NamespaceString& nss, Callable&& handler) {
AutoGetCollection autoColl(opCtx, nss, MODE_IX);
const auto css = CollectionShardingRuntime::get(opCtx, nss);
const auto metadata = css->getCurrentMetadata();
const auto emptyChunkMap =
RangeMap{SimpleBSONObjComparator::kInstance.makeBSONObjIndexedMap<BSONObj>()};
if (!metadata->isSharded()) {
LOG(0) << "Upgrade: skipping orphaned range enumeration for " << nss
<< ", collection is not sharded";
return;
}
auto startingKey = metadata->getMinKey();
while (true) {
auto range = metadata->getNextOrphanRange(emptyChunkMap, startingKey);
if (!range) {
LOG(2) << "Upgrade: Completed orphaned range enumeration for " << nss.toString()
<< " starting from " << redact(startingKey) << ", no orphan ranges remain";
return;
}
handler(*range);
startingKey = range->getMax();
}
}
void submitOrphanRanges(OperationContext* opCtx, const NamespaceString& nss, const UUID& uuid) {
try {
auto version = forceShardFilteringMetadataRefresh(opCtx, nss, true);
if (version == ChunkVersion::UNSHARDED())
return;
LOG(2) << "Upgrade: Cleaning up existing orphans for " << nss << " : " << uuid;
std::vector<RangeDeletionTask> deletions;
forEachOrphanRange(opCtx, nss, [&deletions, &opCtx, &nss, &uuid](const auto& range) {
// Since this is not part of an active migration, the migration UUID and the donor shard
// are set to unused values so that they don't conflict.
RangeDeletionTask task(
UUID::gen(), nss, uuid, ShardId("fromFCVUpgrade"), range, CleanWhenEnum::kDelayed);
deletions.emplace_back(task);
});
if (deletions.empty())
return;
PersistentTaskStore<RangeDeletionTask> store(opCtx,
NamespaceString::kRangeDeletionNamespace);
for (const auto& task : deletions) {
LOG(2) << "Upgrade: Submitting range for cleanup: " << task.getRange() << " from "
<< nss;
store.add(opCtx, task);
}
} catch (ExceptionFor<ErrorCodes::NamespaceNotFound>& e) {
LOG(0) << "Upgrade: Failed to cleanup orphans for " << nss
<< " because the namespace was not found: " << e.what()
<< ", the collection must have been dropped";
}
}
void submitOrphanRangesForCleanup(OperationContext* opCtx) {
auto& catalog = CollectionCatalog::get(opCtx);
const auto& dbs = catalog.getAllDbNames();
for (const auto& dbName : dbs) {
if (dbName == NamespaceString::kLocalDb)
continue;
for (auto collIt = catalog.begin(dbName); collIt != catalog.end(); ++collIt) {
auto uuid = collIt.uuid().get();
auto nss = catalog.lookupNSSByUUID(opCtx, uuid).get();
LOG(2) << "Upgrade: processing collection: " << nss;
submitOrphanRanges(opCtx, nss, uuid);
}
}
}
void persistMigrationCoordinatorLocally(OperationContext* opCtx,
const MigrationCoordinatorDocument& migrationDoc) {
PersistentTaskStore<MigrationCoordinatorDocument> store(
opCtx, NamespaceString::kMigrationCoordinatorsNamespace);
try {
store.add(opCtx, migrationDoc);
} catch (const ExceptionFor<ErrorCodes::DuplicateKey>&) {
// Convert a DuplicateKey error to an anonymous error.
uasserted(
31374,
str::stream() << "While attempting to write migration information for migration "
<< ", found document with the same migration id. Attempted migration: "
<< migrationDoc.toBSON());
}
}
void persistRangeDeletionTaskLocally(OperationContext* opCtx,
const RangeDeletionTask& deletionTask) {
PersistentTaskStore<RangeDeletionTask> store(opCtx, NamespaceString::kRangeDeletionNamespace);
try {
store.add(opCtx, deletionTask);
} catch (const ExceptionFor<ErrorCodes::DuplicateKey>&) {
// Convert a DuplicateKey error to an anonymous error.
uasserted(31375,
str::stream() << "While attempting to write range deletion task for migration "
<< ", found document with the same migration id. Attempted range "
"deletion task: "
<< deletionTask.toBSON());
}
}
void persistCommitDecision(OperationContext* opCtx, const UUID& migrationId) {
PersistentTaskStore<MigrationCoordinatorDocument> store(
opCtx, NamespaceString::kMigrationCoordinatorsNamespace);
store.update(
opCtx,
QUERY(MigrationCoordinatorDocument::kIdFieldName << migrationId),
BSON("$set" << BSON(MigrationCoordinatorDocument::kDecisionFieldName << "committed")));
}
void persistAbortDecision(OperationContext* opCtx, const UUID& migrationId) {
PersistentTaskStore<MigrationCoordinatorDocument> store(
opCtx, NamespaceString::kMigrationCoordinatorsNamespace);
store.update(
opCtx,
QUERY(MigrationCoordinatorDocument::kIdFieldName << migrationId),
BSON("$set" << BSON(MigrationCoordinatorDocument::kDecisionFieldName << "aborted")));
}
void deleteRangeDeletionTaskOnRecipient(OperationContext* opCtx,
const ShardId& recipientId,
const UUID& migrationId) {
write_ops::Delete deleteOp(NamespaceString::kRangeDeletionNamespace);
write_ops::DeleteOpEntry query(BSON(RangeDeletionTask::kIdFieldName << migrationId),
false /*multi*/);
deleteOp.setDeletes({query});
sendToRecipient(opCtx, recipientId, deleteOp);
}
void deleteRangeDeletionTaskLocally(OperationContext* opCtx,
const UUID& deletionTaskId,
const WriteConcernOptions& writeConcern) {
PersistentTaskStore<RangeDeletionTask> store(opCtx, NamespaceString::kRangeDeletionNamespace);
store.remove(opCtx, QUERY(RangeDeletionTask::kIdFieldName << deletionTaskId), writeConcern);
}
void deleteRangeDeletionTasksForCollectionLocally(OperationContext* opCtx,
const UUID& collectionUuid) {
PersistentTaskStore<RangeDeletionTask> store(opCtx, NamespaceString::kRangeDeletionNamespace);
store.remove(opCtx, QUERY(RangeDeletionTask::kCollectionUuidFieldName << collectionUuid));
}
void markAsReadyRangeDeletionTaskOnRecipient(OperationContext* opCtx,
const ShardId& recipientId,
const UUID& migrationId) {
write_ops::Update updateOp(NamespaceString::kRangeDeletionNamespace);
auto queryFilter = BSON(RangeDeletionTask::kIdFieldName << migrationId);
auto updateModification = write_ops::UpdateModification(
BSON("$unset" << BSON(RangeDeletionTask::kPendingFieldName << "")));
write_ops::UpdateOpEntry updateEntry(queryFilter, updateModification);
updateEntry.setMulti(false);
updateEntry.setUpsert(false);
updateOp.setUpdates({updateEntry});
sendToRecipient(opCtx, recipientId, updateOp);
}
void markAsReadyRangeDeletionTaskLocally(OperationContext* opCtx, const UUID& migrationId) {
PersistentTaskStore<RangeDeletionTask> store(opCtx, NamespaceString::kRangeDeletionNamespace);
auto query = QUERY(RangeDeletionTask::kIdFieldName << migrationId);
auto update = BSON("$unset" << BSON(RangeDeletionTask::kPendingFieldName << ""));
store.update(opCtx, query, update);
}
void deleteMigrationCoordinatorDocumentLocally(OperationContext* opCtx, const UUID& migrationId) {
PersistentTaskStore<MigrationCoordinatorDocument> store(
opCtx, NamespaceString::kMigrationCoordinatorsNamespace);
store.remove(opCtx,
QUERY(MigrationCoordinatorDocument::kIdFieldName << migrationId),
{1, WriteConcernOptions::SyncMode::UNSET, Seconds(0)});
}
void ensureChunkVersionIsGreaterThan(OperationContext* opCtx,
const ChunkRange& range,
const ChunkVersion& preMigrationChunkVersion) {
ConfigsvrEnsureChunkVersionIsGreaterThan ensureChunkVersionIsGreaterThanRequest;
ensureChunkVersionIsGreaterThanRequest.setDbName(NamespaceString::kAdminDb);
ensureChunkVersionIsGreaterThanRequest.setMinKey(range.getMin());
ensureChunkVersionIsGreaterThanRequest.setMaxKey(range.getMax());
ensureChunkVersionIsGreaterThanRequest.setVersion(preMigrationChunkVersion);
const auto ensureChunkVersionIsGreaterThanRequestBSON =
ensureChunkVersionIsGreaterThanRequest.toBSON({});
for (int attempts = 1;; attempts++) {
const auto ensureChunkVersionIsGreaterThanResponse =
Grid::get(opCtx)->shardRegistry()->getConfigShard()->runCommandWithFixedRetryAttempts(
opCtx,
ReadPreferenceSetting{ReadPreference::PrimaryOnly},
"admin",
ensureChunkVersionIsGreaterThanRequestBSON,
Shard::RetryPolicy::kIdempotent);
const auto ensureChunkVersionIsGreaterThanStatus =
Shard::CommandResponse::getEffectiveStatus(ensureChunkVersionIsGreaterThanResponse);
if (ensureChunkVersionIsGreaterThanStatus.isOK()) {
break;
}
// If the server is already doing a clean shutdown, join the shutdown.
if (globalInShutdownDeprecated()) {
shutdown(waitForShutdown());
}
opCtx->checkForInterrupt();
LOG(0) << "_configsvrEnsureChunkVersionIsGreaterThan failed after " << attempts
<< " attempts " << causedBy(ensureChunkVersionIsGreaterThanStatus)
<< " . Will try again.";
}
}
void refreshFilteringMetadataUntilSuccess(OperationContext* opCtx, const NamespaceString& nss) {
for (int attempts = 1;; attempts++) {
try {
forceShardFilteringMetadataRefresh(opCtx, nss, true);
break;
} catch (const DBException& ex) {
// If the server is already doing a clean shutdown, join the shutdown.
if (globalInShutdownDeprecated()) {
shutdown(waitForShutdown());
}
opCtx->checkForInterrupt();
LOG(0) << "Failed to refresh metadata for " << nss.ns() << " after " << attempts
<< " attempts " << causedBy(redact(ex.toStatus()))
<< ". Will try to refresh again.";
}
}
}
void resumeMigrationCoordinationsOnStepUp(ServiceContext* serviceContext) {
LOG(0) << "Starting migration coordinator stepup recovery thread.";
auto executor = Grid::get(serviceContext)->getExecutorPool()->getFixedExecutor();
ExecutorFuture<void>(executor).getAsync([serviceContext](const Status& status) {
try {
ThreadClient tc("MigrationCoordinatorStepupRecovery", serviceContext);
{
stdx::lock_guard<Client> lk(*tc.get());
tc->setSystemOperationKillable(lk);
}
auto uniqueOpCtx = tc->makeOperationContext();
auto opCtx = uniqueOpCtx.get();
// Wait for the latest OpTime to be majority committed to ensure any decision that is
// read is on the true branch of history.
// Note (Esha): I don't think this is strictly required for correctness, but it is
// is difficult to reason about, and being pessimistic by waiting for the decision to be
// majority committed does not cost much, since stepup should be rare. It *is* required
// that this node ensure a decision that it itself recovers is majority committed. For
// example, it is possible that this node is a stale primary, and the true primary has
// already sent a *commit* decision and re-received a chunk containing the minKey of
// this migration. In this case, this node would see that the minKey is still owned and
// assume the migration *aborted*. If this node communicated the abort decision to the
// recipient, the recipient (if it had not heard the decision yet) would delete data
// that the recipient actually owns. (The recipient does not currently wait to hear the
// range deletion decision for the first migration before being able to donate (any
// part of) the chunk again.)
auto& replClientInfo = repl::ReplClientInfo::forClient(opCtx->getClient());
replClientInfo.setLastOpToSystemLastOpTime(opCtx);
const auto lastOpTime = replClientInfo.getLastOp();
LOG(0) << "Waiting for OpTime " << lastOpTime << " to become majority committed";
WriteConcernResult unusedWCResult;
uassertStatusOK(
waitForWriteConcern(opCtx,
lastOpTime,
WriteConcernOptions{WriteConcernOptions::kMajority,
WriteConcernOptions::SyncMode::UNSET,
WriteConcernOptions::kNoTimeout},
&unusedWCResult));
PersistentTaskStore<MigrationCoordinatorDocument> store(
opCtx, NamespaceString::kMigrationCoordinatorsNamespace);
Query query;
store.forEach(opCtx, query, [&opCtx](const MigrationCoordinatorDocument& doc) {
LOG(0) << "Recovering migration " << doc.toBSON();
// Create a MigrationCoordinator to complete the coordination.
MigrationCoordinator coordinator(doc.getId(),
doc.getDonorShardId(),
doc.getRecipientShardId(),
doc.getNss(),
doc.getCollectionUuid(),
doc.getRange(),
doc.getPreMigrationChunkVersion());
if (doc.getDecision()) {
// The decision is already known.
coordinator.setMigrationDecision(
(*doc.getDecision()) == DecisionEnum::kCommitted
? MigrationCoordinator::Decision::kCommitted
: MigrationCoordinator::Decision::kAborted);
coordinator.completeMigration(opCtx);
return true;
}
// The decision is not known. Recover the decision from the config server.
ensureChunkVersionIsGreaterThan(
opCtx, doc.getRange(), doc.getPreMigrationChunkVersion());
refreshFilteringMetadataUntilSuccess(opCtx, doc.getNss());
auto refreshedMetadata = [&] {
AutoGetCollection autoColl(opCtx, doc.getNss(), MODE_IS);
auto* const css = CollectionShardingRuntime::get(opCtx, doc.getNss());
return css->getCurrentMetadataIfKnown();
}();
if (!refreshedMetadata || !(*refreshedMetadata)->isSharded() ||
!(*refreshedMetadata)->uuidMatches(doc.getCollectionUuid())) {
LOG(0) << "Even after forced refresh, filtering metadata for namespace in "
"migration coordinator doc "
<< doc.toBSON()
<< (!refreshedMetadata || !(*refreshedMetadata)->isSharded()
? "is not known"
: "has UUID that does not match the collection UUID in the "
"coordinator doc")
<< ". Deleting the range deletion tasks on the donor and recipient as "
"well as the migration coordinator document on this node.";
// TODO (SERVER-45707): Test that range deletion tasks are eventually
// deleted even if the collection is dropped before migration coordination
// is resumed.
deleteRangeDeletionTaskOnRecipient(
opCtx, doc.getRecipientShardId(), doc.getId());
deleteRangeDeletionTaskLocally(opCtx, doc.getId());
coordinator.forgetMigration(opCtx);
return true;
}
if ((*refreshedMetadata)->keyBelongsToMe(doc.getRange().getMin())) {
coordinator.setMigrationDecision(MigrationCoordinator::Decision::kAborted);
} else {
coordinator.setMigrationDecision(MigrationCoordinator::Decision::kCommitted);
}
coordinator.completeMigration(opCtx);
return true;
});
} catch (const DBException& ex) {
LOG(0) << "Failed to resume coordinating migrations on stepup "
<< causedBy(ex.toStatus());
}
});
}
} // namespace migrationutil
} // namespace mongo
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