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/**
* Copyright (C) 2017 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/catalog/sharding_catalog_manager_impl.h"
#include <iomanip>
#include <set>
#include "mongo/base/status_with.h"
#include "mongo/bson/util/bson_extract.h"
#include "mongo/client/connection_string.h"
#include "mongo/client/read_preference.h"
#include "mongo/client/remote_command_targeter.h"
#include "mongo/client/replica_set_monitor.h"
#include "mongo/db/client.h"
#include "mongo/db/commands/feature_compatibility_version.h"
#include "mongo/db/commands/feature_compatibility_version_command_parser.h"
#include "mongo/db/db_raii.h"
#include "mongo/db/namespace_string.h"
#include "mongo/db/operation_context.h"
#include "mongo/db/repl/repl_client_info.h"
#include "mongo/db/repl/repl_set_config.h"
#include "mongo/db/repl/replication_coordinator.h"
#include "mongo/db/s/type_shard_identity.h"
#include "mongo/db/wire_version.h"
#include "mongo/executor/task_executor.h"
#include "mongo/rpc/get_status_from_command_result.h"
#include "mongo/s/catalog/config_server_version.h"
#include "mongo/s/catalog/sharding_catalog_client.h"
#include "mongo/s/catalog/type_database.h"
#include "mongo/s/catalog/type_shard.h"
#include "mongo/s/client/shard.h"
#include "mongo/s/client/shard_registry.h"
#include "mongo/s/cluster_identity_loader.h"
#include "mongo/s/grid.h"
#include "mongo/s/write_ops/batched_command_request.h"
#include "mongo/s/write_ops/batched_command_response.h"
#include "mongo/util/fail_point_service.h"
#include "mongo/util/log.h"
#include "mongo/util/mongoutils/str.h"
#include "mongo/util/scopeguard.h"
namespace mongo {
namespace {
using CallbackHandle = executor::TaskExecutor::CallbackHandle;
using CallbackArgs = executor::TaskExecutor::CallbackArgs;
using RemoteCommandCallbackArgs = executor::TaskExecutor::RemoteCommandCallbackArgs;
using RemoteCommandCallbackFn = executor::TaskExecutor::RemoteCommandCallbackFn;
const Seconds kDefaultFindHostMaxWaitTime(20);
const ReadPreferenceSetting kConfigReadSelector(ReadPreference::Nearest, TagSet{});
const WriteConcernOptions kNoWaitWriteConcern(1, WriteConcernOptions::SyncMode::UNSET, Seconds(0));
MONGO_FP_DECLARE(dontUpsertShardIdentityOnNewShards);
/**
* Generates a unique name to be given to a newly added shard.
*/
StatusWith<std::string> generateNewShardName(OperationContext* opCtx) {
BSONObjBuilder shardNameRegex;
shardNameRegex.appendRegex(ShardType::name(), "^shard");
auto findStatus = Grid::get(opCtx)->shardRegistry()->getConfigShard()->exhaustiveFindOnConfig(
opCtx,
kConfigReadSelector,
repl::ReadConcernLevel::kMajorityReadConcern,
NamespaceString(ShardType::ConfigNS),
shardNameRegex.obj(),
BSON(ShardType::name() << -1),
1);
if (!findStatus.isOK()) {
return findStatus.getStatus();
}
const auto& docs = findStatus.getValue().docs;
int count = 0;
if (!docs.empty()) {
const auto shardStatus = ShardType::fromBSON(docs.front());
if (!shardStatus.isOK()) {
return shardStatus.getStatus();
}
std::istringstream is(shardStatus.getValue().getName().substr(5));
is >> count;
count++;
}
// TODO: fix so that we can have more than 10000 automatically generated shard names
if (count < 9999) {
std::stringstream ss;
ss << "shard" << std::setfill('0') << std::setw(4) << count;
return ss.str();
}
return Status(ErrorCodes::OperationFailed, "unable to generate new shard name");
}
} // namespace
StatusWith<Shard::CommandResponse> ShardingCatalogManagerImpl::_runCommandForAddShard(
OperationContext* opCtx,
RemoteCommandTargeter* targeter,
const std::string& dbName,
const BSONObj& cmdObj) {
auto swHost = targeter->findHost(opCtx, ReadPreferenceSetting{ReadPreference::PrimaryOnly});
if (!swHost.isOK()) {
return swHost.getStatus();
}
auto host = std::move(swHost.getValue());
executor::RemoteCommandRequest request(
host, dbName, cmdObj, rpc::makeEmptyMetadata(), nullptr, Seconds(30));
executor::RemoteCommandResponse response =
Status(ErrorCodes::InternalError, "Internal error running command");
auto swCallbackHandle = _executorForAddShard->scheduleRemoteCommand(
request, [&response](const executor::TaskExecutor::RemoteCommandCallbackArgs& args) {
response = args.response;
});
if (!swCallbackHandle.isOK()) {
return swCallbackHandle.getStatus();
}
// Block until the command is carried out
_executorForAddShard->wait(swCallbackHandle.getValue());
if (response.status == ErrorCodes::ExceededTimeLimit) {
LOG(0) << "Operation timed out with status " << redact(response.status);
}
if (!response.isOK()) {
if (!Shard::shouldErrorBePropagated(response.status.code())) {
return {ErrorCodes::OperationFailed,
str::stream() << "failed to run command " << cmdObj
<< " when attempting to add shard "
<< targeter->connectionString().toString()
<< causedBy(response.status)};
}
return response.status;
}
BSONObj result = response.data.getOwned();
Status commandStatus = getStatusFromCommandResult(result);
if (!Shard::shouldErrorBePropagated(commandStatus.code())) {
commandStatus = {ErrorCodes::OperationFailed,
str::stream() << "failed to run command " << cmdObj
<< " when attempting to add shard "
<< targeter->connectionString().toString()
<< causedBy(commandStatus)};
}
Status writeConcernStatus = getWriteConcernStatusFromCommandResult(result);
if (!Shard::shouldErrorBePropagated(writeConcernStatus.code())) {
writeConcernStatus = {ErrorCodes::OperationFailed,
str::stream() << "failed to satisfy writeConcern for command "
<< cmdObj
<< " when attempting to add shard "
<< targeter->connectionString().toString()
<< causedBy(writeConcernStatus)};
}
return Shard::CommandResponse(std::move(host),
std::move(result),
response.metadata.getOwned(),
std::move(commandStatus),
std::move(writeConcernStatus));
}
StatusWith<boost::optional<ShardType>> ShardingCatalogManagerImpl::_checkIfShardExists(
OperationContext* opCtx,
const ConnectionString& proposedShardConnectionString,
const std::string* proposedShardName,
long long proposedShardMaxSize) {
// Check whether any host in the connection is already part of the cluster.
const auto existingShards = Grid::get(opCtx)->catalogClient(opCtx)->getAllShards(
opCtx, repl::ReadConcernLevel::kLocalReadConcern);
if (!existingShards.isOK()) {
return Status(existingShards.getStatus().code(),
str::stream() << "Failed to load existing shards during addShard"
<< causedBy(existingShards.getStatus().reason()));
}
// Now check if this shard already exists - if it already exists *with the same options* then
// the addShard request can return success early without doing anything more.
for (const auto& existingShard : existingShards.getValue().value) {
auto swExistingShardConnStr = ConnectionString::parse(existingShard.getHost());
if (!swExistingShardConnStr.isOK()) {
return swExistingShardConnStr.getStatus();
}
auto existingShardConnStr = std::move(swExistingShardConnStr.getValue());
// Function for determining if the options for the shard that is being added match the
// options of an existing shard that conflicts with it.
auto shardsAreEquivalent = [&]() {
if (proposedShardName && *proposedShardName != existingShard.getName()) {
return false;
}
if (proposedShardConnectionString.type() != existingShardConnStr.type()) {
return false;
}
if (proposedShardConnectionString.type() == ConnectionString::SET &&
proposedShardConnectionString.getSetName() != existingShardConnStr.getSetName()) {
return false;
}
if (proposedShardMaxSize != existingShard.getMaxSizeMB()) {
return false;
}
return true;
};
if (existingShardConnStr.type() == ConnectionString::SET &&
proposedShardConnectionString.type() == ConnectionString::SET &&
existingShardConnStr.getSetName() == proposedShardConnectionString.getSetName()) {
// An existing shard has the same replica set name as the shard being added.
// If the options aren't the same, then this is an error,
// but if the options match then the addShard operation should be immediately
// considered a success and terminated.
if (shardsAreEquivalent()) {
return {existingShard};
} else {
return {ErrorCodes::IllegalOperation,
str::stream() << "A shard already exists containing the replica set '"
<< existingShardConnStr.getSetName()
<< "'"};
}
}
for (const auto& existingHost : existingShardConnStr.getServers()) {
// Look if any of the hosts in the existing shard are present within the shard trying
// to be added.
for (const auto& addingHost : proposedShardConnectionString.getServers()) {
if (existingHost == addingHost) {
// At least one of the hosts in the shard being added already exists in an
// existing shard. If the options aren't the same, then this is an error,
// but if the options match then the addShard operation should be immediately
// considered a success and terminated.
if (shardsAreEquivalent()) {
return {existingShard};
} else {
return {ErrorCodes::IllegalOperation,
str::stream() << "'" << addingHost.toString() << "' "
<< "is already a member of the existing shard '"
<< existingShard.getHost()
<< "' ("
<< existingShard.getName()
<< ")."};
}
}
}
}
if (proposedShardName && *proposedShardName == existingShard.getName()) {
// If we get here then we're trying to add a shard with the same name as an existing
// shard, but there was no overlap in the hosts between the existing shard and the
// proposed connection string for the new shard.
return {ErrorCodes::IllegalOperation,
str::stream() << "A shard named " << *proposedShardName << " already exists"};
}
}
return {boost::none};
}
StatusWith<ShardType> ShardingCatalogManagerImpl::_validateHostAsShard(
OperationContext* opCtx,
std::shared_ptr<RemoteCommandTargeter> targeter,
const std::string* shardProposedName,
const ConnectionString& connectionString) {
// Check if the node being added is a mongos or a version of mongod too old to speak the current
// communication protocol.
auto swCommandResponse =
_runCommandForAddShard(opCtx, targeter.get(), "admin", BSON("isMaster" << 1));
if (!swCommandResponse.isOK()) {
if (swCommandResponse.getStatus() == ErrorCodes::RPCProtocolNegotiationFailed) {
// Mongos to mongos commands are no longer supported in the wire protocol
// (because mongos does not support OP_COMMAND), similarly for a new mongos
// and an old mongod. So the call will fail in such cases.
// TODO: If/When mongos ever supports opCommands, this logic will break because
// cmdStatus will be OK.
return {ErrorCodes::RPCProtocolNegotiationFailed,
str::stream() << targeter->connectionString().toString()
<< " does not recognize the RPC protocol being used. This is"
<< " likely because it contains a node that is a mongos or an old"
<< " version of mongod."};
} else {
return swCommandResponse.getStatus();
}
}
// Check for a command response error
auto resIsMasterStatus = std::move(swCommandResponse.getValue().commandStatus);
if (!resIsMasterStatus.isOK()) {
return {resIsMasterStatus.code(),
str::stream() << "Error running isMaster against "
<< targeter->connectionString().toString()
<< ": "
<< causedBy(resIsMasterStatus)};
}
auto resIsMaster = std::move(swCommandResponse.getValue().response);
// Check that the node being added is a new enough version.
// If we're running this code, that means the mongos that the addShard request originated from
// must be at least version 3.4 (since 3.2 mongoses don't know about the _configsvrAddShard
// command). Since it is illegal to have v3.4 mongoses with v3.2 shards, we should reject
// adding any shards that are not v3.4. We can determine this by checking that the
// maxWireVersion reported in isMaster is at least COMMANDS_ACCEPT_WRITE_CONCERN.
// TODO(SERVER-25623): This approach won't work to prevent v3.6 mongoses from adding v3.4
// shards, so we'll have to rethink this during the 3.5 development cycle.
long long maxWireVersion;
Status status = bsonExtractIntegerField(resIsMaster, "maxWireVersion", &maxWireVersion);
if (!status.isOK()) {
return Status(status.code(),
str::stream() << "isMaster returned invalid 'maxWireVersion' "
<< "field when attempting to add "
<< connectionString.toString()
<< " as a shard: "
<< status.reason());
}
if (maxWireVersion < WireVersion::COMMANDS_ACCEPT_WRITE_CONCERN) {
return Status(ErrorCodes::IncompatibleServerVersion,
str::stream() << "Cannot add " << connectionString.toString()
<< " as a shard because we detected a mongod with server "
"version older than 3.4.0. It is invalid to add v3.2 and "
"older shards through a v3.4 mongos.");
}
// Check whether there is a master. If there isn't, the replica set may not have been
// initiated. If the connection is a standalone, it will return true for isMaster.
bool isMaster;
status = bsonExtractBooleanField(resIsMaster, "ismaster", &isMaster);
if (!status.isOK()) {
return Status(status.code(),
str::stream() << "isMaster returned invalid 'ismaster' "
<< "field when attempting to add "
<< connectionString.toString()
<< " as a shard: "
<< status.reason());
}
if (!isMaster) {
return {ErrorCodes::NotMaster,
str::stream()
<< connectionString.toString()
<< " does not have a master. If this is a replica set, ensure that it has a"
<< " healthy primary and that the set has been properly initiated."};
}
const std::string providedSetName = connectionString.getSetName();
const std::string foundSetName = resIsMaster["setName"].str();
// Make sure the specified replica set name (if any) matches the actual shard's replica set
if (providedSetName.empty() && !foundSetName.empty()) {
return {ErrorCodes::OperationFailed,
str::stream() << "host is part of set " << foundSetName << "; "
<< "use replica set url format "
<< "<setname>/<server1>,<server2>, ..."};
}
if (!providedSetName.empty() && foundSetName.empty()) {
return {ErrorCodes::OperationFailed,
str::stream() << "host did not return a set name; "
<< "is the replica set still initializing? "
<< resIsMaster};
}
// Make sure the set name specified in the connection string matches the one where its hosts
// belong into
if (!providedSetName.empty() && (providedSetName != foundSetName)) {
return {ErrorCodes::OperationFailed,
str::stream() << "the provided connection string (" << connectionString.toString()
<< ") does not match the actual set name "
<< foundSetName};
}
// Is it a config server?
if (resIsMaster.hasField("configsvr")) {
return {ErrorCodes::OperationFailed,
str::stream() << "Cannot add " << connectionString.toString()
<< " as a shard since it is a config server"};
}
// If the shard is part of a replica set, make sure all the hosts mentioned in the connection
// string are part of the set. It is fine if not all members of the set are mentioned in the
// connection string, though.
if (!providedSetName.empty()) {
std::set<std::string> hostSet;
BSONObjIterator iter(resIsMaster["hosts"].Obj());
while (iter.more()) {
hostSet.insert(iter.next().String()); // host:port
}
if (resIsMaster["passives"].isABSONObj()) {
BSONObjIterator piter(resIsMaster["passives"].Obj());
while (piter.more()) {
hostSet.insert(piter.next().String()); // host:port
}
}
if (resIsMaster["arbiters"].isABSONObj()) {
BSONObjIterator piter(resIsMaster["arbiters"].Obj());
while (piter.more()) {
hostSet.insert(piter.next().String()); // host:port
}
}
for (const auto& hostEntry : connectionString.getServers()) {
const auto& host = hostEntry.toString(); // host:port
if (hostSet.find(host) == hostSet.end()) {
return {ErrorCodes::OperationFailed,
str::stream() << "in seed list " << connectionString.toString() << ", host "
<< host
<< " does not belong to replica set "
<< foundSetName
<< "; found "
<< resIsMaster.toString()};
}
}
}
std::string actualShardName;
if (shardProposedName) {
actualShardName = *shardProposedName;
} else if (!foundSetName.empty()) {
// Default it to the name of the replica set
actualShardName = foundSetName;
}
// Disallow adding shard replica set with name 'config'
if (actualShardName == NamespaceString::kConfigDb) {
return {ErrorCodes::BadValue, "use of shard replica set with name 'config' is not allowed"};
}
// Retrieve the most up to date connection string that we know from the replica set monitor (if
// this is a replica set shard, otherwise it will be the same value as connectionString).
ConnectionString actualShardConnStr = targeter->connectionString();
ShardType shard;
shard.setName(actualShardName);
shard.setHost(actualShardConnStr.toString());
shard.setState(ShardType::ShardState::kShardAware);
return shard;
}
StatusWith<std::vector<std::string>> ShardingCatalogManagerImpl::_getDBNamesListFromShard(
OperationContext* opCtx, std::shared_ptr<RemoteCommandTargeter> targeter) {
auto swCommandResponse = _runCommandForAddShard(
opCtx, targeter.get(), "admin", BSON("listDatabases" << 1 << "nameOnly" << true));
if (!swCommandResponse.isOK()) {
return swCommandResponse.getStatus();
}
auto cmdStatus = std::move(swCommandResponse.getValue().commandStatus);
if (!cmdStatus.isOK()) {
return cmdStatus;
}
auto cmdResult = std::move(swCommandResponse.getValue().response);
std::vector<std::string> dbNames;
for (const auto& dbEntry : cmdResult["databases"].Obj()) {
const auto& dbName = dbEntry["name"].String();
if (!(dbName == NamespaceString::kAdminDb || dbName == NamespaceString::kLocalDb ||
dbName == NamespaceString::kConfigDb)) {
dbNames.push_back(dbName);
}
}
return dbNames;
}
StatusWith<std::string> ShardingCatalogManagerImpl::addShard(
OperationContext* opCtx,
const std::string* shardProposedName,
const ConnectionString& shardConnectionString,
const long long maxSize) {
if (shardConnectionString.type() == ConnectionString::INVALID) {
return {ErrorCodes::BadValue, "Invalid connection string"};
}
if (shardProposedName && shardProposedName->empty()) {
return {ErrorCodes::BadValue, "shard name cannot be empty"};
}
// Only one addShard operation can be in progress at a time.
Lock::ExclusiveLock lk(opCtx->lockState(), _kShardMembershipLock);
// Check if this shard has already been added (can happen in the case of a retry after a network
// error, for example) and thus this addShard request should be considered a no-op.
auto existingShard =
_checkIfShardExists(opCtx, shardConnectionString, shardProposedName, maxSize);
if (!existingShard.isOK()) {
return existingShard.getStatus();
}
if (existingShard.getValue()) {
// These hosts already belong to an existing shard, so report success and terminate the
// addShard request. Make sure to set the last optime for the client to the system last
// optime so that we'll still wait for replication so that this state is visible in the
// committed snapshot.
repl::ReplClientInfo::forClient(opCtx->getClient()).setLastOpToSystemLastOpTime(opCtx);
return existingShard.getValue()->getName();
}
// Force a reload of the ShardRegistry to ensure that, in case this addShard is to re-add a
// replica set that has recently been removed, we have detached the ReplicaSetMonitor for the
// set with that setName from the ReplicaSetMonitorManager and will create a new
// ReplicaSetMonitor when targeting the set below.
// Note: This is necessary because as of 3.4, removeShard is performed by mongos (unlike
// addShard), so the ShardRegistry is not synchronously reloaded on the config server when a
// shard is removed.
if (!Grid::get(opCtx)->shardRegistry()->reload(opCtx)) {
// If the first reload joined an existing one, call reload again to ensure the reload is
// fresh.
Grid::get(opCtx)->shardRegistry()->reload(opCtx);
}
// TODO: Don't create a detached Shard object, create a detached RemoteCommandTargeter instead.
const std::shared_ptr<Shard> shard{
Grid::get(opCtx)->shardRegistry()->createConnection(shardConnectionString)};
invariant(shard);
auto targeter = shard->getTargeter();
auto stopMonitoringGuard = MakeGuard([&] {
if (shardConnectionString.type() == ConnectionString::SET) {
// This is a workaround for the case were we could have some bad shard being
// requested to be added and we put that bad connection string on the global replica set
// monitor registry. It needs to be cleaned up so that when a correct replica set is
// added, it will be recreated.
ReplicaSetMonitor::remove(shardConnectionString.getSetName());
}
});
// Validate the specified connection string may serve as shard at all
auto shardStatus =
_validateHostAsShard(opCtx, targeter, shardProposedName, shardConnectionString);
if (!shardStatus.isOK()) {
return shardStatus.getStatus();
}
ShardType& shardType = shardStatus.getValue();
// Check that none of the existing shard candidate's dbs exist already
auto dbNamesStatus = _getDBNamesListFromShard(opCtx, targeter);
if (!dbNamesStatus.isOK()) {
return dbNamesStatus.getStatus();
}
for (const auto& dbName : dbNamesStatus.getValue()) {
auto dbt = Grid::get(opCtx)->catalogClient(opCtx)->getDatabase(opCtx, dbName);
if (dbt.isOK()) {
const auto& dbDoc = dbt.getValue().value;
return Status(ErrorCodes::OperationFailed,
str::stream() << "can't add shard "
<< "'"
<< shardConnectionString.toString()
<< "'"
<< " because a local database '"
<< dbName
<< "' exists in another "
<< dbDoc.getPrimary());
} else if (dbt != ErrorCodes::NamespaceNotFound) {
return dbt.getStatus();
}
}
// If a name for a shard wasn't provided, generate one
if (shardType.getName().empty()) {
auto result = generateNewShardName(opCtx);
if (!result.isOK()) {
return result.getStatus();
}
shardType.setName(result.getValue());
}
if (maxSize > 0) {
shardType.setMaxSizeMB(maxSize);
}
// The featureCompatibilityVersion should be the same throughout the cluster.
auto versionResponse = _runCommandForAddShard(
opCtx,
targeter.get(),
"admin",
BSON(FeatureCompatibilityVersion::kCommandName << FeatureCompatibilityVersion::toString(
serverGlobalParams.featureCompatibility.version.load())));
if (!versionResponse.isOK()) {
return versionResponse.getStatus();
}
if (!versionResponse.getValue().commandStatus.isOK()) {
return versionResponse.getValue().commandStatus;
}
if (!MONGO_FAIL_POINT(dontUpsertShardIdentityOnNewShards)) {
auto commandRequest = createShardIdentityUpsertForAddShard(opCtx, shardType.getName());
LOG(2) << "going to insert shardIdentity document into shard: " << shardType;
auto swCommandResponse =
_runCommandForAddShard(opCtx, targeter.get(), "admin", commandRequest);
if (!swCommandResponse.isOK()) {
return swCommandResponse.getStatus();
}
auto commandResponse = std::move(swCommandResponse.getValue());
BatchedCommandResponse batchResponse;
auto batchResponseStatus =
Shard::CommandResponse::processBatchWriteResponse(commandResponse, &batchResponse);
if (!batchResponseStatus.isOK()) {
return batchResponseStatus;
}
}
log() << "going to insert new entry for shard into config.shards: " << shardType.toString();
Status result = Grid::get(opCtx)->catalogClient(opCtx)->insertConfigDocument(
opCtx,
ShardType::ConfigNS,
shardType.toBSON(),
ShardingCatalogClient::kMajorityWriteConcern);
if (!result.isOK()) {
log() << "error adding shard: " << shardType.toBSON() << " err: " << result.reason();
return result;
}
// Add all databases which were discovered on the new shard
for (const auto& dbName : dbNamesStatus.getValue()) {
DatabaseType dbt;
dbt.setName(dbName);
dbt.setPrimary(shardType.getName());
dbt.setSharded(false);
Status status = Grid::get(opCtx)->catalogClient(opCtx)->updateDatabase(opCtx, dbName, dbt);
if (!status.isOK()) {
log() << "adding shard " << shardConnectionString.toString()
<< " even though could not add database " << dbName;
}
}
// Record in changelog
BSONObjBuilder shardDetails;
shardDetails.append("name", shardType.getName());
shardDetails.append("host", shardConnectionString.toString());
Grid::get(opCtx)->catalogClient(opCtx)->logChange(
opCtx, "addShard", "", shardDetails.obj(), ShardingCatalogClient::kMajorityWriteConcern);
// Ensure the added shard is visible to this process.
auto shardRegistry = Grid::get(opCtx)->shardRegistry();
if (!shardRegistry->getShard(opCtx, shardType.getName()).isOK()) {
return {ErrorCodes::OperationFailed,
"Could not find shard metadata for shard after adding it. This most likely "
"indicates that the shard was removed immediately after it was added."};
}
stopMonitoringGuard.Dismiss();
return shardType.getName();
}
void ShardingCatalogManagerImpl::appendConnectionStats(executor::ConnectionPoolStats* stats) {
_executorForAddShard->appendConnectionStats(stats);
}
BSONObj ShardingCatalogManagerImpl::createShardIdentityUpsertForAddShard(
OperationContext* opCtx, const std::string& shardName) {
std::unique_ptr<BatchedUpdateDocument> updateDoc(new BatchedUpdateDocument());
BSONObjBuilder query;
query.append("_id", "shardIdentity");
query.append(ShardIdentityType::shardName(), shardName);
query.append(ShardIdentityType::clusterId(), ClusterIdentityLoader::get(opCtx)->getClusterId());
updateDoc->setQuery(query.obj());
BSONObjBuilder update;
{
BSONObjBuilder set(update.subobjStart("$set"));
set.append(
ShardIdentityType::configsvrConnString(),
repl::ReplicationCoordinator::get(opCtx)->getConfig().getConnectionString().toString());
}
updateDoc->setUpdateExpr(update.obj());
updateDoc->setUpsert(true);
std::unique_ptr<BatchedUpdateRequest> updateRequest(new BatchedUpdateRequest());
updateRequest->addToUpdates(updateDoc.release());
BatchedCommandRequest commandRequest(updateRequest.release());
commandRequest.setNS(NamespaceString::kServerConfigurationNamespace);
commandRequest.setWriteConcern(ShardingCatalogClient::kMajorityWriteConcern.toBSON());
return commandRequest.toBSON();
}
} // namespace mongo
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