ClickHouse/programs/server/ReplicasStatusHandler.cpp
2020-05-24 01:24:01 +03:00

106 lines
3.3 KiB
C++

#include "ReplicasStatusHandler.h"
#include <Interpreters/Context.h>
#include <Storages/StorageReplicatedMergeTree.h>
#include <Common/HTMLForm.h>
#include <Common/typeid_cast.h>
#include <Databases/IDatabase.h>
#include <IO/HTTPCommon.h>
#include <Poco/Net/HTTPServerRequest.h>
#include <Poco/Net/HTTPServerResponse.h>
namespace DB
{
ReplicasStatusHandler::ReplicasStatusHandler(IServer & server)
: context(server.context())
{
}
void ReplicasStatusHandler::handleRequest(Poco::Net::HTTPServerRequest & request, Poco::Net::HTTPServerResponse & response)
{
try
{
HTMLForm params(request);
/// Even if lag is small, output detailed information about the lag.
bool verbose = params.get("verbose", "") == "1";
const MergeTreeSettings & settings = context.getMergeTreeSettings();
bool ok = true;
std::stringstream message;
auto databases = DatabaseCatalog::instance().getDatabases();
/// Iterate through all the replicated tables.
for (const auto & db : databases)
{
/// Lazy database can not contain replicated tables
if (db.second->getEngineName() == "Lazy")
continue;
for (auto iterator = db.second->getTablesIterator(); iterator->isValid(); iterator->next())
{
const auto & table = iterator->table();
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 = context.getConfigRef();
setResponseDefaultHeaders(response, config.getUInt("keep_alive_timeout", 10));
if (ok && !verbose)
{
const char * data = "Ok.\n";
response.sendBuffer(data, strlen(data));
}
else
{
response.setStatusAndReason(Poco::Net::HTTPResponse::HTTP_SERVICE_UNAVAILABLE);
response.send() << message.rdbuf();
}
}
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((&Logger::get("ReplicasStatusHandler")), "Cannot send exception to client");
}
}
}
}