blob: d42bcae905531f918db7b531cffb9c230479cf3f [file]
// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements. See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership. The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License. You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied. See the License for the
// specific language governing permissions and limitations
// under the License.
#include "util/s3_util.h"
#include <aws/core/auth/AWSAuthSigner.h>
#include <aws/core/auth/AWSCredentials.h>
#include <aws/core/auth/AWSCredentialsProviderChain.h>
#include <aws/core/client/DefaultRetryStrategy.h>
#include <aws/core/utils/logging/LogLevel.h>
#include <aws/core/utils/logging/LogSystemInterface.h>
#include <aws/core/utils/memory/stl/AWSStringStream.h>
#include <aws/s3/S3Client.h>
#include "util/string_util.h"
#ifdef USE_AZURE
#include <azure/core/diagnostics/logger.hpp>
#include <azure/core/http/curl_transport.hpp>
#include <azure/storage/blobs/blob_container_client.hpp>
#endif
#include <cstdlib>
#include <filesystem>
#include <fstream>
#include <functional>
#include <memory>
#include <ostream>
#include <utility>
#include "common/config.h"
#include "common/logging.h"
#include "common/status.h"
#include "cpp/obj-client/auth/aws_credential_factory.h"
#ifdef USE_AZURE
#include "cpp/obj-client/auth/azure_auth_factory.h"
#include "cpp/obj-client/azure_obj_storage_client.h"
#endif
#include "cloud/config.h"
#include "cpp/aws_logger.h"
#include "cpp/obj-client/rate_limited_obj_storage_client.h"
#include "cpp/obj-client/s3_obj_storage_client.h"
#include "cpp/obj_retry_strategy.h"
#include "cpp/sync_point.h"
#include "cpp/util.h"
#include "exec/scan/scanner_scheduler.h"
#include "runtime/exec_env.h"
#include "util/s3_rate_limiter_manager.h"
#include "util/s3_uri.h"
namespace doris {
namespace {
doris::Status is_s3_conf_valid(const S3ClientConf& conf) {
if (conf.endpoint.empty()) {
return Status::InvalidArgument<false>("Invalid s3 conf, empty endpoint");
}
if (conf.region.empty()) {
return Status::InvalidArgument<false>("Invalid s3 conf, empty region");
}
if (conf.role_arn.empty()) {
// Allow anonymous access when both ak and sk are empty
bool hasAk = !conf.ak.empty();
bool hasSk = !conf.sk.empty();
// Either both credentials are provided or both are empty (anonymous access)
if (hasAk && conf.sk.empty()) {
return Status::InvalidArgument<false>("Invalid s3 conf, empty sk");
}
if (hasSk && conf.ak.empty()) {
return Status::InvalidArgument<false>("Invalid s3 conf, empty ak");
}
}
return Status::OK();
}
ObjStorageResponse make_be_rate_limit_response(S3RateLimitType type,
S3RateLimitRejectReason reason) {
const auto* limit_type = reason == S3RateLimitRejectReason::QPS ? "QPS" : "bytes";
// A local admission rejection is not an S3 HTTP 429. Keep the merged #65420 behavior so S3
// readers do not retry it as provider throttling.
return ObjStorageResponse::rate_limit(
ErrorCode::EXCEEDED_LIMIT, 0,
fmt::format("s3 {} request exceeds {} limit, rejected by BE rate limiter",
to_string(type), limit_type));
}
class BeObjStorageRateLimitPolicy final : public ObjStorageRateLimitPolicy {
public:
ObjStorageAdmission acquire(S3RateLimitType type, size_t estimated_bytes) const override {
auto guard = std::make_shared<S3RateLimitGuard>(type, estimated_bytes);
if (!guard->ok()) {
return ObjStorageAdmission {
.resp = make_be_rate_limit_response(type, guard->reject_reason()),
};
}
return ObjStorageAdmission {
.settle = [guard = std::move(guard)](
size_t actual_bytes) { guard->settle(actual_bytes); },
};
}
};
// Return true is convert `str` to int successfully
bool to_int(std::string_view str, int& res) {
auto [_, ec] = std::from_chars(str.data(), str.data() + str.size(), res);
return ec == std::errc {};
}
#ifdef USE_AZURE
std::string env_or_empty(const char* env_name) {
if (const char* value = std::getenv(env_name); value != nullptr) {
return value;
}
return "";
}
std::string build_azure_tls_debug_context(const std::string& selected_ca_file) {
bool selected_ca_exists = false;
bool selected_ca_readable = false;
if (!selected_ca_file.empty()) {
std::error_code ec;
selected_ca_exists = std::filesystem::exists(selected_ca_file, ec) && !ec;
std::ifstream input(selected_ca_file);
selected_ca_readable = input.good();
}
return fmt::format(
"tls_debug(ca_cert_file_paths='{}', selected_ca_file='{}', selected_ca_exists={}, "
"selected_ca_readable={}, SSL_CERT_FILE='{}', CURL_CA_BUNDLE='{}', SSL_CERT_DIR='{}')",
config::ca_cert_file_paths, selected_ca_file, selected_ca_exists, selected_ca_readable,
env_or_empty("SSL_CERT_FILE"), env_or_empty("CURL_CA_BUNDLE"),
env_or_empty("SSL_CERT_DIR"));
}
#endif
constexpr char USE_PATH_STYLE[] = "use_path_style";
constexpr char AZURE_PROVIDER_STRING[] = "AZURE";
constexpr char S3_PROVIDER[] = "provider";
constexpr char S3_AK[] = "AWS_ACCESS_KEY";
constexpr char S3_SK[] = "AWS_SECRET_KEY";
constexpr char S3_ENDPOINT[] = "AWS_ENDPOINT";
constexpr char S3_REGION[] = "AWS_REGION";
constexpr char S3_TOKEN[] = "AWS_TOKEN";
constexpr char S3_MAX_CONN_SIZE[] = "AWS_MAX_CONNECTIONS";
constexpr char S3_REQUEST_TIMEOUT_MS[] = "AWS_REQUEST_TIMEOUT_MS";
constexpr char S3_CONN_TIMEOUT_MS[] = "AWS_CONNECTION_TIMEOUT_MS";
constexpr char S3_NEED_OVERRIDE_ENDPOINT[] = "AWS_NEED_OVERRIDE_ENDPOINT";
constexpr char S3_ROLE_ARN[] = "AWS_ROLE_ARN";
constexpr char S3_EXTERNAL_ID[] = "AWS_EXTERNAL_ID";
constexpr char S3_CREDENTIALS_PROVIDER_TYPE[] = "AWS_CREDENTIALS_PROVIDER_TYPE";
} // namespace
S3ClientFactory::S3ClientFactory() {
_aws_options = Aws::SDKOptions {};
auto logLevel = static_cast<Aws::Utils::Logging::LogLevel>(config::aws_log_level);
_aws_options.loggingOptions.logLevel = logLevel;
_aws_options.loggingOptions.logger_create_fn = [logLevel] {
return std::make_shared<DorisAWSLogger>(logLevel);
};
Aws::InitAPI(_aws_options);
_get_ca_cert_file_path();
#ifdef USE_AZURE
auto azureLogLevel =
static_cast<Azure::Core::Diagnostics::Logger::Level>(config::azure_log_level);
Azure::Core::Diagnostics::Logger::SetLevel(azureLogLevel);
Azure::Core::Diagnostics::Logger::SetListener(
[&](Azure::Core::Diagnostics::Logger::Level level, const std::string& message) {
switch (level) {
case Azure::Core::Diagnostics::Logger::Level::Verbose:
LOG(INFO) << message;
break;
case Azure::Core::Diagnostics::Logger::Level::Informational:
LOG(INFO) << message;
break;
case Azure::Core::Diagnostics::Logger::Level::Warning:
LOG(WARNING) << message;
break;
case Azure::Core::Diagnostics::Logger::Level::Error:
LOG(ERROR) << message;
break;
default:
LOG(WARNING) << "Unknown level: " << static_cast<int>(level)
<< ", message: " << message;
break;
}
});
#endif
}
S3ClientFactory::~S3ClientFactory() {
Aws::ShutdownAPI(_aws_options);
}
S3ClientFactory& S3ClientFactory::instance() {
static S3ClientFactory ret;
return ret;
}
Result<std::shared_ptr<io::ObjStorageClient>> S3ClientFactory::create(const S3ClientConf& s3_conf) {
RETURN_IF_ERROR_RESULT(is_s3_conf_valid(s3_conf));
#ifdef BE_TEST
{
std::lock_guard l(_lock);
if (_test_client_creator) {
return _test_client_creator(s3_conf);
}
}
#endif
{
std::lock_guard l(_lock);
auto it = _cache.find(s3_conf);
if (it != _cache.end()) {
return it->second;
}
}
auto client_result = (s3_conf.provider == io::ObjStorageProvider::AZURE)
? _create_azure_client(s3_conf)
: _create_s3_client(s3_conf);
if (!client_result.has_value()) {
return ResultError(std::move(client_result).error());
}
auto obj_client = std::move(client_result).value();
if (!config::is_cloud_mode() || s3_conf.is_internal_bucket) {
obj_client = std::make_shared<io::RateLimitedObjStorageClient>(
std::move(obj_client), std::make_shared<BeObjStorageRateLimitPolicy>());
}
{
std::lock_guard l(_lock);
auto [it, _] = _cache.emplace(s3_conf, std::move(obj_client));
return it->second;
}
}
#ifdef BE_TEST
void S3ClientFactory::set_client_creator_for_test(
std::function<std::shared_ptr<io::ObjStorageClient>(const S3ClientConf&)> creator) {
std::lock_guard l(_lock);
_test_client_creator = std::move(creator);
}
void S3ClientFactory::clear_client_creator_for_test() {
std::lock_guard l(_lock);
_test_client_creator = nullptr;
}
#endif
Result<std::shared_ptr<io::ObjStorageClient>> S3ClientFactory::_create_azure_client(
const S3ClientConf& s3_conf) {
#ifdef USE_AZURE
const std::string container_name = s3_conf.bucket;
std::string uri = fmt::format("{}/{}", s3_conf.endpoint, container_name);
if (s3_conf.endpoint.find("://") == std::string::npos) {
uri = "https://" + uri;
}
Azure::Storage::Blobs::BlobClientOptions options;
options.Retry.StatusCodes.insert(Azure::Core::Http::HttpStatusCode::TooManyRequests);
options.Retry.MaxRetries = config::max_s3_client_retry;
options.PerRetryPolicies.emplace_back(std::make_unique<AzureRetryRecordPolicy>());
auto ca_cert_file_path = _get_ca_cert_file_path();
if (!ca_cert_file_path.empty()) {
Azure::Core::Http::CurlTransportOptions curl_options;
curl_options.CAInfo = ca_cert_file_path;
options.Transport.Transport =
std::make_shared<Azure::Core::Http::CurlTransport>(std::move(curl_options));
}
std::string normalized_uri = normalize_http_uri(uri);
VLOG_DEBUG << "uri:" << uri << ", normalized_uri:" << normalized_uri;
std::string tls_debug_context = build_azure_tls_debug_context(ca_cert_file_path);
auto built = AzureAuthFactory::create(uri,
{
.type = AzureCredentialType::SHARED_KEY,
.account_name = s3_conf.ak,
.account_key = s3_conf.sk,
},
std::move(options));
if (!built) {
return ResultError(
Status::InvalidArgument("failed to create Azure client: {}", built.error));
}
LOG_INFO("create one azure client with {}", s3_conf.to_string());
return std::make_shared<io::AzureObjStorageClient>(
std::move(built.container_client),
ObjStorageEndpointInfo {
.endpoint = s3_conf.endpoint,
.ak = s3_conf.ak,
.sk = s3_conf.sk,
.tls_debug_context = std::move(tls_debug_context),
},
std::move(built.shared_key_credential));
#else
return ResultError(Status::NotSupported(
"BE is not compiled with azure support, export BUILD_AZURE=ON before building"));
#endif
}
std::string S3ClientFactory::_get_ca_cert_file_path() {
std::lock_guard lock(_ca_cert_lock);
if (_ca_cert_file_path.empty()) {
_ca_cert_file_path = get_valid_ca_cert_path(doris::split(config::ca_cert_file_paths, ";"));
}
return _ca_cert_file_path;
}
AwsCredentialResult S3ClientFactory::create_aws_credentials_provider(const S3ClientConf& s3_conf) {
auto sts_config = S3ClientFactory::getClientConfiguration();
auto ca_cert_file_path = _get_ca_cert_file_path();
if (!ca_cert_file_path.empty()) {
sts_config.caFile = ca_cert_file_path;
}
return AwsCredentialFactory::create({
.version = config::aws_credentials_provider_version == "v2"
? AwsCredentialProviderVersion::V2
: AwsCredentialProviderVersion::V1,
.access_key = s3_conf.ak,
.secret_key = s3_conf.sk,
.session_token = s3_conf.token,
.provider_type = s3_conf.cred_provider_type,
.role_arn = s3_conf.role_arn,
.external_id = s3_conf.external_id,
.empty_credentials = EmptyCredentialsBehavior::ANONYMOUS,
.sts_client_config = std::move(sts_config),
});
}
Result<std::shared_ptr<io::ObjStorageClient>> S3ClientFactory::_create_s3_client(
const S3ClientConf& s3_conf) {
TEST_SYNC_POINT_RETURN_WITH_VALUE(
"s3_client_factory::create",
std::make_shared<io::S3ObjStorageClient>(std::make_shared<Aws::S3::S3Client>(),
ObjStorageEndpointInfo {}));
Aws::Client::ClientConfiguration aws_config = S3ClientFactory::getClientConfiguration();
if (s3_conf.need_override_endpoint) {
aws_config.endpointOverride = s3_conf.endpoint;
}
aws_config.region = s3_conf.region;
auto ca_cert_file_path = _get_ca_cert_file_path();
if (!ca_cert_file_path.empty()) {
aws_config.caFile = ca_cert_file_path;
}
if (s3_conf.max_connections > 0) {
aws_config.maxConnections = s3_conf.max_connections;
} else {
aws_config.maxConnections = 102400;
}
aws_config.requestTimeoutMs = 30000;
if (s3_conf.request_timeout_ms > 0) {
aws_config.requestTimeoutMs = s3_conf.request_timeout_ms;
}
if (s3_conf.connect_timeout_ms > 0) {
aws_config.connectTimeoutMs = s3_conf.connect_timeout_ms;
}
set_s3_client_default_http_scheme(aws_config, config::s3_client_http_scheme);
aws_config.retryStrategy = std::make_shared<S3CustomRetryStrategy>(
config::max_s3_client_retry /*scaleFactor = 25*/, /*retry_slow_down=*/true);
auto credentials = create_aws_credentials_provider(s3_conf);
if (!credentials) {
return ResultError(Status::InvalidArgument("failed to create AWS credential provider: {}",
credentials.error));
}
std::shared_ptr<Aws::S3::S3Client> new_client = std::make_shared<Aws::S3::S3Client>(
std::move(credentials.provider), std::move(aws_config),
Aws::Client::AWSAuthV4Signer::PayloadSigningPolicy::Never,
s3_conf.use_virtual_addressing);
auto provider_client = std::make_shared<io::S3ObjStorageClient>(
std::move(new_client), ObjStorageEndpointInfo {
.endpoint = s3_conf.endpoint,
.ak = s3_conf.ak,
.sk = s3_conf.sk,
});
LOG_INFO("create one s3 client with {}", s3_conf.to_string());
return provider_client;
}
Status S3ClientFactory::convert_properties_to_s3_conf(
const std::map<std::string, std::string>& prop, const S3URI& s3_uri, S3Conf* s3_conf) {
StringCaseMap<std::string> properties(prop.begin(), prop.end());
if (auto it = properties.find(S3_AK); it != properties.end()) {
s3_conf->client_conf.ak = it->second;
}
if (auto it = properties.find(S3_SK); it != properties.end()) {
s3_conf->client_conf.sk = it->second;
}
if (auto it = properties.find(S3_TOKEN); it != properties.end()) {
s3_conf->client_conf.token = it->second;
}
if (auto it = properties.find(S3_ENDPOINT); it != properties.end()) {
s3_conf->client_conf.endpoint = it->second;
}
if (auto it = properties.find(S3_NEED_OVERRIDE_ENDPOINT); it != properties.end()) {
s3_conf->client_conf.need_override_endpoint = (it->second == "true");
}
if (auto it = properties.find(S3_REGION); it != properties.end()) {
s3_conf->client_conf.region = it->second;
}
if (auto it = properties.find(S3_MAX_CONN_SIZE); it != properties.end()) {
if (!to_int(it->second, s3_conf->client_conf.max_connections)) {
return Status::InvalidArgument("invalid {} value \"{}\"", S3_MAX_CONN_SIZE, it->second);
}
}
if (auto it = properties.find(S3_REQUEST_TIMEOUT_MS); it != properties.end()) {
if (!to_int(it->second, s3_conf->client_conf.request_timeout_ms)) {
return Status::InvalidArgument("invalid {} value \"{}\"", S3_REQUEST_TIMEOUT_MS,
it->second);
}
}
if (auto it = properties.find(S3_CONN_TIMEOUT_MS); it != properties.end()) {
if (!to_int(it->second, s3_conf->client_conf.connect_timeout_ms)) {
return Status::InvalidArgument("invalid {} value \"{}\"", S3_CONN_TIMEOUT_MS,
it->second);
}
}
if (auto it = properties.find(S3_PROVIDER); it != properties.end()) {
// S3 Provider properties should be case insensitive.
if (0 == strcasecmp(it->second.c_str(), AZURE_PROVIDER_STRING)) {
s3_conf->client_conf.provider = io::ObjStorageProvider::AZURE;
}
}
if (s3_uri.get_bucket().empty()) {
return Status::InvalidArgument("Invalid S3 URI {}, bucket is not specified",
s3_uri.to_string());
}
s3_conf->bucket = s3_uri.get_bucket();
// For azure's compatibility
s3_conf->client_conf.bucket = s3_uri.get_bucket();
s3_conf->prefix = "";
// See https://sdk.amazonaws.com/cpp/api/LATEST/class_aws_1_1_s3_1_1_s3_client.html
s3_conf->client_conf.use_virtual_addressing = true;
if (auto it = properties.find(USE_PATH_STYLE); it != properties.end()) {
s3_conf->client_conf.use_virtual_addressing = it->second != "true";
}
if (auto it = properties.find(S3_ROLE_ARN); it != properties.end()) {
// Keep provider type as Default unless explicitly configured by
// AWS_CREDENTIALS_PROVIDER_TYPE, consistent with FE behavior.
s3_conf->client_conf.role_arn = it->second;
}
if (auto it = properties.find(S3_EXTERNAL_ID); it != properties.end()) {
s3_conf->client_conf.external_id = it->second;
}
if (auto it = properties.find(S3_CREDENTIALS_PROVIDER_TYPE); it != properties.end()) {
s3_conf->client_conf.cred_provider_type = cred_provider_type_from_string(it->second);
}
if (auto st = is_s3_conf_valid(s3_conf->client_conf); !st.ok()) {
return st;
}
return Status::OK();
}
static CredProviderType cred_provider_type_from_thrift(TCredProviderType::type cred_provider_type) {
switch (cred_provider_type) {
case TCredProviderType::DEFAULT:
return CredProviderType::Default;
case TCredProviderType::SIMPLE:
return CredProviderType::Simple;
case TCredProviderType::INSTANCE_PROFILE:
return CredProviderType::InstanceProfile;
case TCredProviderType::ENV:
return CredProviderType::Env;
case TCredProviderType::SYSTEM_PROPERTIES:
return CredProviderType::SystemProperties;
case TCredProviderType::WEB_IDENTITY:
return CredProviderType::WebIdentity;
case TCredProviderType::CONTAINER:
return CredProviderType::Container;
case TCredProviderType::ANONYMOUS:
return CredProviderType::Anonymous;
default:
__builtin_unreachable();
LOG(WARNING) << "Invalid TCredProviderType value: " << cred_provider_type
<< ", use default instead.";
return CredProviderType::Default;
}
}
S3Conf S3Conf::get_s3_conf(const cloud::ObjectStoreInfoPB& info) {
S3Conf ret {
.bucket = info.bucket(),
.prefix = info.prefix(),
.client_conf {
.endpoint = info.endpoint(),
.region = info.region(),
.ak = info.ak(),
.sk = info.sk(),
.token = {},
.bucket = info.bucket(),
.provider = io::ObjStorageProvider::AWS,
.use_virtual_addressing =
info.has_use_path_style() ? !info.use_path_style() : true,
.role_arn = info.role_arn(),
.external_id = info.external_id(),
// ObjectStoreInfoPB always describes a storage vault, i.e. a Doris
// internal bucket in cloud mode.
.is_internal_bucket = true,
},
.sse_enabled = info.sse_enabled(),
};
if (info.has_cred_provider_type()) {
ret.client_conf.cred_provider_type = cred_provider_type_from_pb(info.cred_provider_type());
}
io::ObjStorageProvider type = io::ObjStorageProvider::AWS;
switch (info.provider()) {
case cloud::ObjectStoreInfoPB_Provider_OSS:
type = io::ObjStorageProvider::OSS;
break;
case cloud::ObjectStoreInfoPB_Provider_S3:
type = io::ObjStorageProvider::AWS;
break;
case cloud::ObjectStoreInfoPB_Provider_COS:
type = io::ObjStorageProvider::COS;
break;
case cloud::ObjectStoreInfoPB_Provider_OBS:
type = io::ObjStorageProvider::OBS;
break;
case cloud::ObjectStoreInfoPB_Provider_BOS:
type = io::ObjStorageProvider::BOS;
break;
case cloud::ObjectStoreInfoPB_Provider_GCP:
type = io::ObjStorageProvider::GCP;
break;
case cloud::ObjectStoreInfoPB_Provider_AZURE:
type = io::ObjStorageProvider::AZURE;
break;
case cloud::ObjectStoreInfoPB_Provider_TOS:
type = io::ObjStorageProvider::TOS;
break;
default:
__builtin_unreachable();
LOG_FATAL("unknown provider type {}, info {}", info.provider(), ret.to_string());
}
ret.client_conf.provider = type;
return ret;
}
S3Conf S3Conf::get_s3_conf(const TS3StorageParam& param) {
S3Conf ret {
.bucket = param.bucket,
.prefix = param.root_path,
.client_conf = {
.endpoint = param.endpoint,
.region = param.region,
.ak = param.ak,
.sk = param.sk,
.token = param.token,
.bucket = param.bucket,
.provider = io::ObjStorageProvider::AWS,
.max_connections = param.max_conn,
.request_timeout_ms = param.request_timeout_ms,
.connect_timeout_ms = param.conn_timeout_ms,
// When using cold heat separation in minio, user might use ip address directly,
// which needs enable use_virtual_addressing to true
.use_virtual_addressing = !param.use_path_style,
.role_arn = param.role_arn,
.external_id = param.external_id,
}};
if (param.__isset.cred_provider_type) {
ret.client_conf.cred_provider_type =
cred_provider_type_from_thrift(param.cred_provider_type);
}
io::ObjStorageProvider type = io::ObjStorageProvider::AWS;
switch (param.provider) {
case TObjStorageType::UNKNOWN:
LOG_INFO("Receive one legal storage resource, set provider type to aws, param detail {}",
ret.to_string());
type = io::ObjStorageProvider::AWS;
break;
case TObjStorageType::AWS:
type = io::ObjStorageProvider::AWS;
break;
case TObjStorageType::AZURE:
type = io::ObjStorageProvider::AZURE;
break;
case TObjStorageType::BOS:
type = io::ObjStorageProvider::BOS;
break;
case TObjStorageType::COS:
type = io::ObjStorageProvider::COS;
break;
case TObjStorageType::OBS:
type = io::ObjStorageProvider::OBS;
break;
case TObjStorageType::OSS:
type = io::ObjStorageProvider::OSS;
break;
case TObjStorageType::GCP:
type = io::ObjStorageProvider::GCP;
break;
case TObjStorageType::TOS:
type = io::ObjStorageProvider::TOS;
break;
default:
LOG_FATAL("unknown provider type {}, info {}", param.provider, ret.to_string());
__builtin_unreachable();
}
ret.client_conf.provider = type;
return ret;
}
std::string hide_access_key(const std::string& ak) {
std::string key = ak;
size_t key_len = key.length();
size_t reserved_count;
if (key_len > 7) {
reserved_count = 6;
} else if (key_len > 2) {
reserved_count = key_len - 2;
} else {
reserved_count = 0;
}
size_t x_count = key_len - reserved_count;
size_t left_x_count = (x_count + 1) / 2;
if (left_x_count > 0) {
key.replace(0, left_x_count, left_x_count, 'x');
}
if (x_count - left_x_count > 0) {
key.replace(key_len - (x_count - left_x_count), x_count - left_x_count,
x_count - left_x_count, 'x');
}
return key;
}
} // end namespace doris