ClickHouse/src/Server/ReplicasStatusHandler.cpp
2023-12-20 16:46:29 -05:00

136 lines
4.6 KiB
C++

#include <Server/ReplicasStatusHandler.h>
#include <Databases/IDatabase.h>
#include <IO/HTTPCommon.h>
#include <Interpreters/Context.h>
#include <Server/HTTP/HTMLForm.h>
#include <Server/HTTPHandlerFactory.h>
#include <Server/HTTPHandlerRequestFilter.h>
#include <Server/IServer.h>
#include <Storages/StorageReplicatedMergeTree.h>
#include <Common/typeid_cast.h>
#include <Poco/Net/HTTPRequestHandlerFactory.h>
#include <Poco/Net/HTTPServerRequest.h>
#include <Poco/Net/HTTPServerResponse.h>
namespace DB
{
ReplicasStatusHandler::ReplicasStatusHandler(IServer & server) : WithContext(server.context())
{
}
void ReplicasStatusHandler::handleRequest(HTTPServerRequest & request, HTTPServerResponse & response, const ProfileEvents::Event & /*write_event*/)
{
try
{
HTMLForm params(getContext()->getSettingsRef(), request);
const auto & config = getContext()->getConfigRef();
const MergeTreeSettings & settings = getContext()->getReplicatedMergeTreeSettings();
/// Even if lag is small, output detailed information about the lag.
bool verbose = false;
bool enable_verbose = config.getBool("enable_verbose_replicas_status", true);
if (params.get("verbose", "") == "1" && enable_verbose)
verbose = true;
bool ok = true;
WriteBufferFromOwnString message;
auto databases = DatabaseCatalog::instance().getDatabases();
/// Iterate through all the replicated tables.
for (const auto & db : databases)
{
/// Check if database can contain replicated tables
if (!db.second->canContainMergeTreeTables())
continue;
for (auto iterator = db.second->getTablesIterator(getContext()); iterator->isValid(); iterator->next())
{
const auto & table = iterator->table();
if (!table)
continue;
StorageReplicatedMergeTree * table_replicated = dynamic_cast<StorageReplicatedMergeTree *>(table.get());
if (!table_replicated)
continue;
time_t absolute_delay = 0;
time_t relative_delay = 0;
if (!table_replicated->isTableReadOnly())
{
table_replicated->getReplicaDelays(absolute_delay, relative_delay);
if ((settings.min_absolute_delay_to_close && absolute_delay >= static_cast<time_t>(settings.min_absolute_delay_to_close))
|| (settings.min_relative_delay_to_close && relative_delay >= static_cast<time_t>(settings.min_relative_delay_to_close)))
ok = false;
message << backQuoteIfNeed(db.first) << "." << backQuoteIfNeed(iterator->name())
<< ":\tAbsolute delay: " << absolute_delay << ". Relative delay: " << relative_delay << ".\n";
}
else
{
message << backQuoteIfNeed(db.first) << "." << backQuoteIfNeed(iterator->name())
<< ":\tis readonly. \n";
}
}
}
const auto & server_settings = getContext()->getServerSettings();
setResponseDefaultHeaders(response, server_settings.keep_alive_timeout.totalSeconds());
if (!ok)
{
response.setStatusAndReason(Poco::Net::HTTPResponse::HTTP_SERVICE_UNAVAILABLE);
if (enable_verbose)
verbose = true;
}
if (verbose)
*response.send() << message.str();
else
{
const char * data = "Ok.\n";
response.sendBuffer(data, strlen(data));
}
}
catch (...)
{
tryLogCurrentException("ReplicasStatusHandler");
try
{
response.setStatusAndReason(Poco::Net::HTTPResponse::HTTP_INTERNAL_SERVER_ERROR);
if (!response.sent())
{
/// We have not sent anything yet and we don't even know if we need to compress response.
response.send()->writeln(getCurrentExceptionMessage(false));
}
}
catch (...)
{
LOG_ERROR((&Poco::Logger::get("ReplicasStatusHandler")), "Cannot send exception to client");
}
}
}
HTTPRequestHandlerFactoryPtr createReplicasStatusHandlerFactory(IServer & server,
const Poco::Util::AbstractConfiguration & config,
const std::string & config_prefix)
{
auto factory = std::make_shared<HandlingRuleHTTPHandlerFactory<ReplicasStatusHandler>>(server);
factory->addFiltersFromConfig(config, config_prefix);
return factory;
}
}