Extract S3 logic

This commit is contained in:
Antonio Andelic 2022-09-21 11:53:54 +00:00
parent fc6c1faa57
commit eefbbf53e8
5 changed files with 365 additions and 290 deletions

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@ -45,6 +45,7 @@ if (BUILD_STANDALONE_KEEPER)
${CMAKE_CURRENT_SOURCE_DIR}/../../src/Coordination/KeeperLogStore.cpp
${CMAKE_CURRENT_SOURCE_DIR}/../../src/Coordination/KeeperServer.cpp
${CMAKE_CURRENT_SOURCE_DIR}/../../src/Coordination/KeeperSnapshotManager.cpp
${CMAKE_CURRENT_SOURCE_DIR}/../../src/Coordination/KeeperSnapshotManagerS3.cpp
${CMAKE_CURRENT_SOURCE_DIR}/../../src/Coordination/KeeperStateMachine.cpp
${CMAKE_CURRENT_SOURCE_DIR}/../../src/Coordination/KeeperStateManager.cpp
${CMAKE_CURRENT_SOURCE_DIR}/../../src/Coordination/KeeperStorage.cpp

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@ -9,23 +9,6 @@
#include <Common/checkStackSize.h>
#include <Common/CurrentMetrics.h>
#if USE_AWS_S3
#include <Core/UUID.h>
#include <IO/S3Common.h>
#include <IO/WriteBufferFromS3.h>
#include <IO/ReadBufferFromS3.h>
#include <IO/ReadHelpers.h>
#include <IO/S3/PocoHTTPClient.h>
#include <IO/WriteHelpers.h>
#include <IO/copyData.h>
#include <aws/core/auth/AWSCredentials.h>
#include <aws/s3/S3Client.h>
#include <aws/s3/S3Errors.h>
#include <aws/s3/model/HeadObjectRequest.h>
#include <aws/s3/model/DeleteObjectRequest.h>
#endif
#include <future>
#include <chrono>
@ -54,14 +37,9 @@ namespace ErrorCodes
KeeperDispatcher::KeeperDispatcher()
: responses_queue(std::numeric_limits<size_t>::max())
#if USE_AWS_S3
, snapshots_s3_queue(std::numeric_limits<size_t>::max())
#endif
, configuration_and_settings(std::make_shared<KeeperConfigurationAndSettings>())
, log(&Poco::Logger::get("KeeperDispatcher"))
{
}
{}
void KeeperDispatcher::requestThread()
{
@ -220,16 +198,11 @@ void KeeperDispatcher::snapshotThread()
{
[[maybe_unused]] auto snapshot_path = task.create_snapshot(std::move(task.snapshot));
#if USE_AWS_S3
if (snapshot_path.empty())
continue;
if (isLeader() && getSnapshotS3Client() != nullptr)
{
if (!snapshots_s3_queue.push(snapshot_path))
LOG_WARNING(log, "Failed to add snapshot {} to S3 queue", snapshot_path);
}
#endif
if (isLeader())
snapshot_s3.uploadSnapshot(snapshot_path);
}
catch (...)
{
@ -238,222 +211,6 @@ void KeeperDispatcher::snapshotThread()
}
}
#if USE_AWS_S3
struct KeeperDispatcher::S3Configuration
{
S3Configuration(S3::URI uri_, S3::AuthSettings auth_settings_, std::shared_ptr<const Aws::S3::S3Client> client_)
: uri(std::move(uri_))
, auth_settings(std::move(auth_settings_))
, client(std::move(client_))
{}
S3::URI uri;
S3::AuthSettings auth_settings;
std::shared_ptr<const Aws::S3::S3Client> client;
};
void KeeperDispatcher::updateS3Configuration(const Poco::Util::AbstractConfiguration & config)
{
try
{
const std::string config_prefix = "keeper_server.s3_snapshot";
if (!config.has(config_prefix))
{
std::lock_guard client_lock{snapshot_s3_client_mutex};
if (snapshot_s3_client)
LOG_INFO(log, "S3 configuration was removed");
snapshot_s3_client = nullptr;
return;
}
auto auth_settings = S3::AuthSettings::loadFromConfig(config_prefix, config);
auto endpoint = config.getString(config_prefix + ".endpoint");
auto new_uri = S3::URI{Poco::URI(endpoint)};
std::unique_lock client_lock{snapshot_s3_client_mutex};
if (snapshot_s3_client && snapshot_s3_client->client && auth_settings == snapshot_s3_client->auth_settings
&& snapshot_s3_client->uri.uri == new_uri.uri)
return;
LOG_INFO(log, "S3 configuration was updated");
client_lock.unlock();
auto credentials = Aws::Auth::AWSCredentials(auth_settings.access_key_id, auth_settings.secret_access_key);
HeaderCollection headers = auth_settings.headers;
static constexpr size_t s3_max_redirects = 10;
static constexpr bool enable_s3_requests_logging = false;
if (!new_uri.key.empty())
{
LOG_ERROR(log, "Invalid endpoint defined for S3, it shouldn't contain key, endpoint: {}", endpoint);
return;
}
S3::PocoHTTPClientConfiguration client_configuration = S3::ClientFactory::instance().createClientConfiguration(
auth_settings.region,
RemoteHostFilter(), s3_max_redirects,
enable_s3_requests_logging,
/* for_disk_s3 = */ false);
client_configuration.endpointOverride = new_uri.endpoint;
auto client = S3::ClientFactory::instance().create(
client_configuration,
new_uri.is_virtual_hosted_style,
credentials.GetAWSAccessKeyId(),
credentials.GetAWSSecretKey(),
auth_settings.server_side_encryption_customer_key_base64,
std::move(headers),
auth_settings.use_environment_credentials.value_or(false),
auth_settings.use_insecure_imds_request.value_or(false));
auto new_client = std::make_shared<KeeperDispatcher::S3Configuration>(std::move(new_uri), std::move(auth_settings), std::move(client));
client_lock.lock();
snapshot_s3_client = std::move(new_client);
client_lock.unlock();
LOG_INFO(log, "S3 client was updated");
}
catch (...)
{
LOG_ERROR(log, "Failed to create an S3 client for snapshots");
tryLogCurrentException(__PRETTY_FUNCTION__);
}
}
void KeeperDispatcher::snapshotS3Thread()
{
setThreadName("KeeperS3SnpT");
auto uuid = UUIDHelpers::generateV4();
while (!shutdown_called)
{
std::string snapshot_path;
if (!snapshots_s3_queue.pop(snapshot_path))
break;
if (shutdown_called)
break;
try
{
auto s3_client = getSnapshotS3Client();
if (s3_client == nullptr)
continue;
LOG_INFO(log, "Will try to upload snapshot on {} to S3", snapshot_path);
ReadBufferFromFile snapshot_file(snapshot_path);
S3Settings::ReadWriteSettings read_write_settings;
read_write_settings.upload_part_size_multiply_parts_count_threshold = 10000;
const auto create_writer = [&](const auto & key)
{
return WriteBufferFromS3
{
s3_client->client,
s3_client->uri.bucket,
key,
read_write_settings
};
};
auto snapshot_name = fs::path(snapshot_path).filename().string();
auto lock_file = fmt::format(".{}_LOCK", snapshot_name);
const auto file_exists = [&](const auto & key)
{
Aws::S3::Model::HeadObjectRequest request;
request.SetBucket(s3_client->uri.bucket);
request.SetKey(key);
auto outcome = s3_client->client->HeadObject(request);
if (outcome.IsSuccess())
return true;
const auto & error = outcome.GetError();
if (error.GetErrorType() != Aws::S3::S3Errors::NO_SUCH_KEY && error.GetErrorType() != Aws::S3::S3Errors::RESOURCE_NOT_FOUND)
throw S3Exception(error.GetErrorType(), "Failed to verify existence of lock file: {}", error.GetMessage());
return false;
};
if (file_exists(snapshot_name))
{
LOG_ERROR(log, "Snapshot {} already exists", snapshot_name);
continue;
}
// First we need to verify that there isn't already a lock file for the snapshot we want to upload
if (file_exists(lock_file))
{
LOG_ERROR(log, "Lock file for {} already, exists. Probably a different node is already uploading the snapshot", snapshot_name);
continue;
}
// We write our UUID to lock file
LOG_DEBUG(log, "Trying to create a lock file");
WriteBufferFromS3 lock_writer = create_writer(lock_file);
writeUUIDText(uuid, lock_writer);
lock_writer.finalize();
const auto read_lock_file = [&]() -> std::string
{
ReadBufferFromS3 lock_reader
{
s3_client->client,
s3_client->uri.bucket,
lock_file,
"",
1,
{}
};
std::string read_uuid;
readStringUntilEOF(read_uuid, lock_reader);
return read_uuid;
};
// We read back the written UUID, if it's the same we can upload the file
auto read_uuid = read_lock_file();
if (read_uuid != toString(uuid))
{
LOG_ERROR(log, "Failed to create a lock file");
continue;
}
WriteBufferFromS3 snapshot_writer = create_writer(snapshot_name);
copyData(snapshot_file, snapshot_writer);
snapshot_writer.finalize();
LOG_INFO(log, "Successfully uploaded {} to S3", snapshot_path);
LOG_INFO(log, "Removing lock file");
Aws::S3::Model::DeleteObjectRequest delete_request;
delete_request.SetBucket(s3_client->uri.bucket);
delete_request.SetKey(lock_file);
auto delete_outcome = s3_client->client->DeleteObject(delete_request);
if (!delete_outcome.IsSuccess())
throw S3Exception(delete_outcome.GetError().GetMessage(), delete_outcome.GetError().GetErrorType());
}
catch (...)
{
LOG_INFO(log, "Failure during upload of {} to S3", snapshot_path);
tryLogCurrentException(__PRETTY_FUNCTION__);
}
}
}
#endif
void KeeperDispatcher::setResponse(int64_t session_id, const Coordination::ZooKeeperResponsePtr & response)
{
std::lock_guard lock(session_to_response_callback_mutex);
@ -539,9 +296,7 @@ void KeeperDispatcher::initialize(const Poco::Util::AbstractConfiguration & conf
responses_thread = ThreadFromGlobalPool([this] { responseThread(); });
snapshot_thread = ThreadFromGlobalPool([this] { snapshotThread(); });
#if USE_AWS_S3
snapshot_s3_thread = ThreadFromGlobalPool([this] { snapshotS3Thread(); });
#endif
snapshot_s3.startup();
server = std::make_unique<KeeperServer>(configuration_and_settings, config, responses_queue, snapshots_queue);
@ -607,11 +362,7 @@ void KeeperDispatcher::shutdown()
if (snapshot_thread.joinable())
snapshot_thread.join();
#if USE_AWS_S3
snapshots_s3_queue.finish();
if (snapshot_s3_thread.joinable())
snapshot_s3_thread.join();
#endif
snapshot_s3.shutdown();
update_configuration_queue.finish();
if (update_configuration_thread.joinable())
@ -803,14 +554,6 @@ void KeeperDispatcher::forceWaitAndProcessResult(RaftAppendResult & result, Keep
requests_for_sessions.clear();
}
#if USE_AWS_S3
std::shared_ptr<KeeperDispatcher::S3Configuration> KeeperDispatcher::getSnapshotS3Client() const
{
std::lock_guard lock{snapshot_s3_client_mutex};
return snapshot_s3_client;
}
#endif
int64_t KeeperDispatcher::getSessionID(int64_t session_timeout_ms)
{
/// New session id allocation is a special request, because we cannot process it in normal
@ -951,9 +694,7 @@ void KeeperDispatcher::updateConfiguration(const Poco::Util::AbstractConfigurati
throw Exception(ErrorCodes::SYSTEM_ERROR, "Cannot push configuration update to queue");
}
#if USE_AWS_S3
updateS3Configuration(config);
#endif
snapshot_s3.updateS3Configuration(config);
}
void KeeperDispatcher::updateKeeperStatLatency(uint64_t process_time_ms)

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@ -15,6 +15,7 @@
#include <Coordination/CoordinationSettings.h>
#include <Coordination/Keeper4LWInfo.h>
#include <Coordination/KeeperConnectionStats.h>
#include <Coordination/KeeperSnapshotManagerS3.h>
namespace DB
{
@ -36,11 +37,6 @@ private:
ResponsesQueue responses_queue;
SnapshotsQueue snapshots_queue{1};
#if USE_AWS_S3
using SnapshotBackupQueue = ConcurrentBoundedQueue<std::string>;
SnapshotBackupQueue snapshots_s3_queue;
#endif
/// More than 1k updates is definitely misconfiguration.
UpdateConfigurationQueue update_configuration_queue{1000};
@ -67,10 +63,6 @@ private:
ThreadFromGlobalPool session_cleaner_thread;
/// Dumping new snapshots to disk
ThreadFromGlobalPool snapshot_thread;
#if USE_AWS_S3
/// Upload new snapshots to S3
ThreadFromGlobalPool snapshot_s3_thread;
#endif
/// Apply or wait for configuration changes
ThreadFromGlobalPool update_configuration_thread;
@ -86,11 +78,7 @@ private:
/// Counter for new session_id requests.
std::atomic<int64_t> internal_session_id_counter{0};
#if USE_AWS_S3
struct S3Configuration;
mutable std::mutex snapshot_s3_client_mutex;
std::shared_ptr<S3Configuration> snapshot_s3_client;
#endif
KeeperSnapshotManagerS3 snapshot_s3;
/// Thread put requests to raft
void requestThread();
@ -100,10 +88,6 @@ private:
void sessionCleanerTask();
/// Thread create snapshots in the background
void snapshotThread();
#if USE_AWS_S3
/// Thread upload snapshots to S3 in the background
void snapshotS3Thread();
#endif
/// Thread apply or wait configuration changes from leader
void updateConfigurationThread();
@ -117,10 +101,6 @@ private:
/// Clears both arguments
void forceWaitAndProcessResult(RaftAppendResult & result, KeeperStorage::RequestsForSessions & requests_for_sessions);
#if USE_AWS_S3
std::shared_ptr<S3Configuration> getSnapshotS3Client() const;
#endif
public:
/// Just allocate some objects, real initialization is done by `intialize method`
KeeperDispatcher();
@ -146,9 +126,6 @@ public:
/// Registered in ConfigReloader callback. Add new configuration changes to
/// update_configuration_queue. Keeper Dispatcher apply them asynchronously.
void updateConfiguration(const Poco::Util::AbstractConfiguration & config);
#if USE_AWS_S3
void updateS3Configuration(const Poco::Util::AbstractConfiguration & config);
#endif
/// Shutdown internal keeper parts (server, state machine, log storage, etc)
void shutdown();

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@ -0,0 +1,293 @@
#include <Coordination/KeeperSnapshotManagerS3.h>
#if USE_AWS_S3
#include <Core/UUID.h>
#include <Common/Exception.h>
#include <Common/setThreadName.h>
#include <IO/S3Common.h>
#include <IO/WriteBufferFromS3.h>
#include <IO/ReadBufferFromS3.h>
#include <IO/ReadBufferFromFile.h>
#include <IO/ReadHelpers.h>
#include <IO/S3/PocoHTTPClient.h>
#include <IO/WriteHelpers.h>
#include <IO/copyData.h>
#include <aws/core/auth/AWSCredentials.h>
#include <aws/s3/S3Client.h>
#include <aws/s3/S3Errors.h>
#include <aws/s3/model/HeadObjectRequest.h>
#include <aws/s3/model/DeleteObjectRequest.h>
#include <filesystem>
namespace fs = std::filesystem;
namespace DB
{
struct KeeperSnapshotManagerS3::S3Configuration
{
S3Configuration(S3::URI uri_, S3::AuthSettings auth_settings_, std::shared_ptr<const Aws::S3::S3Client> client_)
: uri(std::move(uri_))
, auth_settings(std::move(auth_settings_))
, client(std::move(client_))
{}
S3::URI uri;
S3::AuthSettings auth_settings;
std::shared_ptr<const Aws::S3::S3Client> client;
};
KeeperSnapshotManagerS3::KeeperSnapshotManagerS3()
: snapshots_s3_queue(std::numeric_limits<size_t>::max())
, log(&Poco::Logger::get("KeeperSnapshotManagerS3"))
{}
void KeeperSnapshotManagerS3::updateS3Configuration(const Poco::Util::AbstractConfiguration & config)
{
try
{
const std::string config_prefix = "keeper_server.s3_snapshot";
if (!config.has(config_prefix))
{
std::lock_guard client_lock{snapshot_s3_client_mutex};
if (snapshot_s3_client)
LOG_INFO(log, "S3 configuration was removed");
snapshot_s3_client = nullptr;
return;
}
auto auth_settings = S3::AuthSettings::loadFromConfig(config_prefix, config);
auto endpoint = config.getString(config_prefix + ".endpoint");
auto new_uri = S3::URI{Poco::URI(endpoint)};
std::unique_lock client_lock{snapshot_s3_client_mutex};
if (snapshot_s3_client && snapshot_s3_client->client && auth_settings == snapshot_s3_client->auth_settings
&& snapshot_s3_client->uri.uri == new_uri.uri)
return;
LOG_INFO(log, "S3 configuration was updated");
client_lock.unlock();
auto credentials = Aws::Auth::AWSCredentials(auth_settings.access_key_id, auth_settings.secret_access_key);
HeaderCollection headers = auth_settings.headers;
static constexpr size_t s3_max_redirects = 10;
static constexpr bool enable_s3_requests_logging = false;
if (!new_uri.key.empty())
{
LOG_ERROR(log, "Invalid endpoint defined for S3, it shouldn't contain key, endpoint: {}", endpoint);
return;
}
S3::PocoHTTPClientConfiguration client_configuration = S3::ClientFactory::instance().createClientConfiguration(
auth_settings.region,
RemoteHostFilter(), s3_max_redirects,
enable_s3_requests_logging,
/* for_disk_s3 = */ false);
client_configuration.endpointOverride = new_uri.endpoint;
auto client = S3::ClientFactory::instance().create(
client_configuration,
new_uri.is_virtual_hosted_style,
credentials.GetAWSAccessKeyId(),
credentials.GetAWSSecretKey(),
auth_settings.server_side_encryption_customer_key_base64,
std::move(headers),
auth_settings.use_environment_credentials.value_or(false),
auth_settings.use_insecure_imds_request.value_or(false));
auto new_client = std::make_shared<KeeperSnapshotManagerS3::S3Configuration>(std::move(new_uri), std::move(auth_settings), std::move(client));
client_lock.lock();
snapshot_s3_client = std::move(new_client);
client_lock.unlock();
LOG_INFO(log, "S3 client was updated");
}
catch (...)
{
LOG_ERROR(log, "Failed to create an S3 client for snapshots");
tryLogCurrentException(__PRETTY_FUNCTION__);
}
}
std::shared_ptr<KeeperSnapshotManagerS3::S3Configuration> KeeperSnapshotManagerS3::getSnapshotS3Client() const
{
std::lock_guard lock{snapshot_s3_client_mutex};
return snapshot_s3_client;
}
void KeeperSnapshotManagerS3::snapshotS3Thread()
{
setThreadName("KeeperS3SnpT");
auto uuid = UUIDHelpers::generateV4();
while (!shutdown_called)
{
std::string snapshot_path;
if (!snapshots_s3_queue.pop(snapshot_path))
break;
if (shutdown_called)
break;
try
{
auto s3_client = getSnapshotS3Client();
if (s3_client == nullptr)
continue;
LOG_INFO(log, "Will try to upload snapshot on {} to S3", snapshot_path);
ReadBufferFromFile snapshot_file(snapshot_path);
S3Settings::ReadWriteSettings read_write_settings;
read_write_settings.upload_part_size_multiply_parts_count_threshold = 10000;
const auto create_writer = [&](const auto & key)
{
return WriteBufferFromS3
{
s3_client->client,
s3_client->uri.bucket,
key,
read_write_settings
};
};
auto snapshot_name = fs::path(snapshot_path).filename().string();
auto lock_file = fmt::format(".{}_LOCK", snapshot_name);
const auto file_exists = [&](const auto & key)
{
Aws::S3::Model::HeadObjectRequest request;
request.SetBucket(s3_client->uri.bucket);
request.SetKey(key);
auto outcome = s3_client->client->HeadObject(request);
if (outcome.IsSuccess())
return true;
const auto & error = outcome.GetError();
if (error.GetErrorType() != Aws::S3::S3Errors::NO_SUCH_KEY && error.GetErrorType() != Aws::S3::S3Errors::RESOURCE_NOT_FOUND)
throw S3Exception(error.GetErrorType(), "Failed to verify existence of lock file: {}", error.GetMessage());
return false;
};
if (file_exists(snapshot_name))
{
LOG_ERROR(log, "Snapshot {} already exists", snapshot_name);
continue;
}
// First we need to verify that there isn't already a lock file for the snapshot we want to upload
if (file_exists(lock_file))
{
LOG_ERROR(log, "Lock file for {} already, exists. Probably a different node is already uploading the snapshot", snapshot_name);
continue;
}
// We write our UUID to lock file
LOG_DEBUG(log, "Trying to create a lock file");
WriteBufferFromS3 lock_writer = create_writer(lock_file);
writeUUIDText(uuid, lock_writer);
lock_writer.finalize();
const auto read_lock_file = [&]() -> std::string
{
ReadBufferFromS3 lock_reader
{
s3_client->client,
s3_client->uri.bucket,
lock_file,
"",
1,
{}
};
std::string read_uuid;
readStringUntilEOF(read_uuid, lock_reader);
return read_uuid;
};
// We read back the written UUID, if it's the same we can upload the file
auto read_uuid = read_lock_file();
if (read_uuid != toString(uuid))
{
LOG_ERROR(log, "Failed to create a lock file");
continue;
}
WriteBufferFromS3 snapshot_writer = create_writer(snapshot_name);
copyData(snapshot_file, snapshot_writer);
snapshot_writer.finalize();
LOG_INFO(log, "Successfully uploaded {} to S3", snapshot_path);
LOG_INFO(log, "Removing lock file");
Aws::S3::Model::DeleteObjectRequest delete_request;
delete_request.SetBucket(s3_client->uri.bucket);
delete_request.SetKey(lock_file);
auto delete_outcome = s3_client->client->DeleteObject(delete_request);
if (!delete_outcome.IsSuccess())
throw S3Exception(delete_outcome.GetError().GetMessage(), delete_outcome.GetError().GetErrorType());
}
catch (...)
{
LOG_INFO(log, "Failure during upload of {} to S3", snapshot_path);
tryLogCurrentException(__PRETTY_FUNCTION__);
}
}
}
void KeeperSnapshotManagerS3::uploadSnapshot(const std::string & path)
{
if (getSnapshotS3Client() == nullptr)
return;
if (!snapshots_s3_queue.push(path))
LOG_WARNING(log, "Failed to add snapshot {} to S3 queue", path);
}
void KeeperSnapshotManagerS3::startup()
{
snapshot_s3_thread = ThreadFromGlobalPool([this] { snapshotS3Thread(); });
}
void KeeperSnapshotManagerS3::shutdown()
{
if (shutdown_called)
return;
LOG_DEBUG(log, "Shutting down KeeperSnapshotManagerS3");
shutdown_called = true;
try
{
snapshots_s3_queue.finish();
if (snapshot_s3_thread.joinable())
snapshot_s3_thread.join();
}
catch (...)
{
tryLogCurrentException(__PRETTY_FUNCTION__);
}
LOG_INFO(log, "KeeperSnapshotManagerS3 shut down");
}
}
#endif

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@ -0,0 +1,63 @@
#pragma once
#include <Common/config.h>
#include <config_core.h>
#include <Poco/Util/AbstractConfiguration.h>
#if USE_AWS_S3
#include <Common/ConcurrentBoundedQueue.h>
#include <Common/ThreadPool.h>
#include <Common/logger_useful.h>
#include <string>
#endif
namespace DB
{
#if USE_AWS_S3
class KeeperSnapshotManagerS3
{
public:
KeeperSnapshotManagerS3();
void updateS3Configuration(const Poco::Util::AbstractConfiguration & config);
void uploadSnapshot(const std::string & path);
void startup();
void shutdown();
private:
using SnapshotS3Queue = ConcurrentBoundedQueue<std::string>;
SnapshotS3Queue snapshots_s3_queue;
/// Upload new snapshots to S3
ThreadFromGlobalPool snapshot_s3_thread;
struct S3Configuration;
mutable std::mutex snapshot_s3_client_mutex;
std::shared_ptr<S3Configuration> snapshot_s3_client;
std::atomic<bool> shutdown_called{false};
Poco::Logger * log;
/// Thread upload snapshots to S3 in the background
void snapshotS3Thread();
std::shared_ptr<S3Configuration> getSnapshotS3Client() const;
};
#else
class KeeperSnapshotManagerS3
{
public:
KeeperSnapshotManagerS3() = default;
void updateS3Configuration(const Poco::Util::AbstractConfiguration &) {}
void uploadSnapshot(const std::string &) {}
void startup() {}
void shutdown() {}
};
#endif
}