ClickHouse/dbms/programs/server/TCPHandler.h
2019-05-28 21:30:10 +03:00

181 lines
5.0 KiB
C++

#pragma once
#include <Poco/Net/TCPServerConnection.h>
#include <Common/getFQDNOrHostName.h>
#include <Common/CurrentMetrics.h>
#include <Common/Stopwatch.h>
#include <Core/Protocol.h>
#include <Core/QueryProcessingStage.h>
#include <IO/Progress.h>
#include <DataStreams/BlockIO.h>
#include <Interpreters/InternalTextLogsQueue.h>
#include <Client/TimeoutSetter.h>
#include "IServer.h"
namespace CurrentMetrics
{
extern const Metric TCPConnection;
}
namespace Poco { class Logger; }
namespace DB
{
class ColumnsDescription;
/// State of query processing.
struct QueryState
{
/// Identifier of the query.
String query_id;
QueryProcessingStage::Enum stage = QueryProcessingStage::Complete;
Protocol::Compression compression = Protocol::Compression::Disable;
/// From where to read data for INSERT.
std::shared_ptr<ReadBuffer> maybe_compressed_in;
BlockInputStreamPtr block_in;
/// Where to write result data.
std::shared_ptr<WriteBuffer> maybe_compressed_out;
BlockOutputStreamPtr block_out;
/// Query text.
String query;
/// Streams of blocks, that are processing the query.
BlockIO io;
/// Is request cancelled
bool is_cancelled = false;
/// empty or not
bool is_empty = true;
/// Data was sent.
bool sent_all_data = false;
/// Request requires data from the client (INSERT, but not INSERT SELECT).
bool need_receive_data_for_insert = false;
/// Request requires data from client for function input()
bool need_receive_data_for_input = false;
/// temporary place for incoming data block for input()
Block block_for_input;
/// sample block from StorageInput
Block input_header;
/// To output progress, the difference after the previous sending of progress.
Progress progress;
/// Timeouts setter for current query
std::unique_ptr<TimeoutSetter> timeout_setter;
/// A queue with internal logs that will be passed to client
InternalTextLogsQueuePtr logs_queue;
BlockOutputStreamPtr logs_block_out;
void reset()
{
*this = QueryState();
}
bool empty()
{
return is_empty;
}
};
class TCPHandler : public Poco::Net::TCPServerConnection
{
public:
TCPHandler(IServer & server_, const Poco::Net::StreamSocket & socket_)
: Poco::Net::TCPServerConnection(socket_)
, server(server_)
, log(&Poco::Logger::get("TCPHandler"))
, connection_context(server.context())
, query_context(server.context())
{
server_display_name = server.config().getString("display_name", getFQDNOrHostName());
}
void run();
/// This method is called right before the query execution.
virtual void customizeContext(DB::Context & /*context*/) {}
private:
IServer & server;
Poco::Logger * log;
String client_name;
UInt64 client_version_major = 0;
UInt64 client_version_minor = 0;
UInt64 client_version_patch = 0;
UInt64 client_revision = 0;
Context connection_context;
std::optional<Context> query_context;
/// Streams for reading/writing from/to client connection socket.
std::shared_ptr<ReadBuffer> in;
std::shared_ptr<WriteBuffer> out;
/// Time after the last check to stop the request and send the progress.
Stopwatch after_check_cancelled;
Stopwatch after_send_progress;
String default_database;
/// At the moment, only one ongoing query in the connection is supported at a time.
QueryState state;
CurrentMetrics::Increment metric_increment{CurrentMetrics::TCPConnection};
/// It is the name of the server that will be sent to the client.
String server_display_name;
void runImpl();
void receiveHello();
bool receivePacket();
void receiveQuery();
bool receiveData();
bool readDataNext(const size_t & poll_interval, const int & receive_timeout);
void readData(const Settings & global_settings);
std::tuple<size_t, int> getReadTimeouts(const Settings & global_settings);
/// Process INSERT query
void processInsertQuery(const Settings & global_settings);
/// Process a request that does not require the receiving of data blocks from the client
void processOrdinaryQuery();
void processTablesStatusRequest();
void sendHello();
void sendData(const Block & block); /// Write a block to the network.
void sendLogData(const Block & block);
void sendTableColumns(const ColumnsDescription & columns);
void sendException(const Exception & e, bool with_stack_trace);
void sendProgress();
void sendLogs();
void sendEndOfStream();
void sendProfileInfo();
void sendTotals();
void sendExtremes();
/// Creates state.block_in/block_out for blocks read/write, depending on whether compression is enabled.
void initBlockInput();
void initBlockOutput(const Block & block);
void initLogsBlockOutput(const Block & block);
bool isQueryCancelled();
/// This function is called from different threads.
void updateProgress(const Progress & value);
};
}