ClickHouse/src/Server/ReplicasStatusHandler.cpp
Azat Khuzhin b698a4ff65 Apply changes to http handlers on fly without server restart
This has been implemented by simply restarting http servers in case of
http_handlers directive in configuration xml had been changed.

But, for this I have to change the handlers interface to accept
configuration separatelly, since the configuration that contains in the
server is the configuration with which server had been started.

Signed-off-by: Azat Khuzhin <a.khuzhin@semrush.com>
Co-authored-by: Antonio Andelic
2022-09-12 17:34:51 +02:00

121 lines
4.0 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)
{
try
{
HTMLForm params(getContext()->getSettingsRef(), request);
/// Even if lag is small, output detailed information about the lag.
bool verbose = params.get("verbose", "") == "1";
const MergeTreeSettings & settings = getContext()->getReplicatedMergeTreeSettings();
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;
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";
}
}
const auto & config = getContext()->getConfigRef();
setResponseDefaultHeaders(response, config.getUInt("keep_alive_timeout", 10));
if (!ok)
{
response.setStatusAndReason(Poco::Net::HTTPResponse::HTTP_SERVICE_UNAVAILABLE);
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() << getCurrentExceptionMessage(false) << std::endl;
}
}
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;
}
}