ClickHouse/programs/server/Server.h

#pragma once

#include <Server/IServer.h>
#include <Daemon/BaseDaemon.h>

/** Server provides three interfaces:
  * 1. HTTP, GRPC - simple interfaces for any applications.
  * 2. TCP - interface for native clickhouse-client and for server to server internal communications.
  *    More rich and efficient, but less compatible
  *     - data is transferred by columns;
  *     - data is transferred compressed;
  *    Allows to get more information in response.
  * 3. Interserver HTTP - for replication.
  */

namespace DB
{

class Server : public BaseDaemon, public IServer
{
public:
    using ServerApplication::run;

    Poco::Util::LayeredConfiguration & config() const override { return BaseDaemon::config(); }

    Poco::Logger & logger() const override { return BaseDaemon::logger(); }

    ContextMutablePtr context() const override { return global_context; }

    bool isCancelled() const override { return BaseDaemon::isCancelled(); }

    void defineOptions(Poco::Util::OptionSet & _options) override;

protected:
    int run() override;

    void initialize(Application & self) override;

    void uninitialize() override;

    int main(const std::vector<std::string> & args) override;

    std::string getDefaultCorePath() const override;

private:
    ContextMutablePtr global_context;
    /// Updated/recent config, to compare http_handlers
    ConfigurationPtr latest_config;
};

}