c7b0b25494
After subscription management was moved onto controller level a bunch of code can be dropped: - passing migration notifier beyond controller - event_notifier's _stopped bit - event_notifier .stop() method - event_notifier empty constructor and destrictor - generic_server's on_stop virtual method Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
121 lines
3.7 KiB
C++
121 lines
3.7 KiB
C++
/*
|
|
* Copyright (C) 2021-present ScyllaDB
|
|
*/
|
|
|
|
/*
|
|
* This file is part of Scylla.
|
|
*
|
|
* Scylla is free software: you can redistribute it and/or modify
|
|
* it under the terms of the GNU Affero General Public License as published by
|
|
* the Free Software Foundation, either version 3 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* Scylla is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with Scylla. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#pragma once
|
|
|
|
#include "log.hh"
|
|
|
|
#include "seastarx.hh"
|
|
|
|
#include <seastar/core/future.hh>
|
|
#include <seastar/core/gate.hh>
|
|
#include <seastar/net/api.hh>
|
|
#include <seastar/net/tls.hh>
|
|
|
|
#include <boost/intrusive/list.hpp>
|
|
|
|
namespace generic_server {
|
|
|
|
class server;
|
|
|
|
// A generic TCP connection.
|
|
//
|
|
// This class is used in tandem with the `server`class to implement a protocol
|
|
// specific TCP connection.
|
|
//
|
|
// Protocol specific classes are expected to override the `process_request`
|
|
// member function to perform request processing. This base class provides a
|
|
// `_read_buf` and a `_write_buf` for reading requests and writing responses.
|
|
class connection : public boost::intrusive::list_base_hook<> {
|
|
protected:
|
|
server& _server;
|
|
connected_socket _fd;
|
|
input_stream<char> _read_buf;
|
|
output_stream<char> _write_buf;
|
|
future<> _ready_to_respond = make_ready_future<>();
|
|
seastar::gate _pending_requests_gate;
|
|
|
|
public:
|
|
connection(server& server, connected_socket&& fd);
|
|
virtual ~connection();
|
|
|
|
virtual future<> process();
|
|
|
|
virtual void handle_error(future<>&& f) = 0;
|
|
|
|
virtual future<> process_request() = 0;
|
|
|
|
virtual void on_connection_close();
|
|
|
|
virtual future<> shutdown();
|
|
};
|
|
|
|
// A generic TCP socket server.
|
|
//
|
|
// This class can be used as a base for a protocol specific TCP socket server
|
|
// that listens to incoming connections and processes requests coming over the
|
|
// connection.
|
|
//
|
|
// The provides a `listen` member function that creates a TCP server socket and
|
|
// registers it to the Seastar reactor. The class also provides a `stop` member
|
|
// function that can be used to safely stop the server.
|
|
//
|
|
// Protocol specific classes that inherit `server` are expected to also inherit
|
|
// a connection class from `connection` and override the `make_connection` member
|
|
// function to create a protocol specific connection upon `accept`.
|
|
class server {
|
|
friend class connection;
|
|
|
|
protected:
|
|
sstring _server_name;
|
|
logging::logger& _logger;
|
|
bool _stopping = false;
|
|
promise<> _all_connections_stopped;
|
|
uint64_t _current_connections = 0;
|
|
uint64_t _connections_being_accepted = 0;
|
|
uint64_t _total_connections = 0;
|
|
future<> _stopped = _all_connections_stopped.get_future();
|
|
boost::intrusive::list<connection> _connections_list;
|
|
std::vector<server_socket> _listeners;
|
|
|
|
public:
|
|
server(const sstring& server_name, logging::logger& logger);
|
|
|
|
virtual ~server();
|
|
|
|
future<> stop();
|
|
|
|
future<> listen(socket_address addr, std::shared_ptr<seastar::tls::credentials_builder> creds, bool is_shard_aware, bool keepalive);
|
|
|
|
future<> do_accepts(int which, bool keepalive, socket_address server_addr);
|
|
|
|
protected:
|
|
virtual seastar::shared_ptr<connection> make_connection(socket_address server_addr, connected_socket&& fd, socket_address addr) = 0;
|
|
|
|
virtual future<> advertise_new_connection(shared_ptr<connection> conn);
|
|
|
|
virtual future<> unadvertise_connection(shared_ptr<connection> conn);
|
|
|
|
void maybe_stop();
|
|
};
|
|
|
|
}
|