ceph/src/seastar/include/seastar/websocket/server.hh

   1 /*
   2  * This file is open source software, licensed to you under the terms
   3  * of the Apache License, Version 2.0 (the "License").  See the NOTICE file
   4  * distributed with this work for additional information regarding copyright
   5  * ownership.  You may not use this file except in compliance with the License.
   6  *
   7  * You may obtain a copy of the License at
   8  *
   9  *   http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing,
  12  * software distributed under the License is distributed on an
  13  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
  14  * KIND, either express or implied.  See the License for the
  15  * specific language governing permissions and limitations
  16  * under the License.
  17  */
  18 /*
  19  * Copyright 2021 ScyllaDB
  20  */
  21
  22 #pragma once
  23
  24 #include <seastar/http/request_parser.hh>
  25 #include <seastar/core/seastar.hh>
  26 #include <seastar/core/sstring.hh>
  27 #include <seastar/net/api.hh>
  28 #include <seastar/core/gate.hh>
  29 #include <seastar/core/queue.hh>
  30 #include <seastar/core/when_all.hh>
  31
  32 namespace seastar::experimental::websocket {
  33
  34 class server;
  35 struct reply {
  36     //TODO: implement
  37 };
  38
  39 /*!
  40  * \brief an error in handling a WebSocket connection
  41  */
  42 class exception : std::exception {
  43     std::string _msg;
  44 public:
  45     exception(std::string_view msg) : _msg(msg) {}
  46     const char* what() const noexcept {
  47         return _msg.c_str();
  48     }
  49 };
  50
  51 /*!
  52  * \brief a WebSocket connection
  53  */
  54 class connection : public boost::intrusive::list_base_hook<> {
  55     server& _server;
  56     connected_socket _fd;
  57     input_stream<char> _read_buf;
  58     output_stream<char> _write_buf;
  59     http_request_parser _http_parser;
  60     std::unique_ptr<reply> _resp;
  61     queue<std::unique_ptr<reply>> _replies{10};
  62     bool _done = false;
  63 public:
  64     /*!
  65      * \param server owning \ref server
  66      * \param fd established socket used for communication
  67      */
  68     connection(server& server, connected_socket&& fd)
  69         : _server(server)
  70         , _fd(std::move(fd))
  71         , _read_buf(_fd.input())
  72         , _write_buf(_fd.output())
  73     {
  74         on_new_connection();
  75     }
  76     ~connection();
  77
  78     /*!
  79      * \brief serve WebSocket protocol on a connection
  80      */
  81     future<> process();
  82     /*!
  83      * \brief close the socket
  84      */
  85     void shutdown();
  86
  87 protected:
  88     future<> read_loop();
  89     future<> read_one();
  90     future<> read_http_upgrade_request();
  91     future<> response_loop();
  92     void on_new_connection();
  93 };
  94
  95 /*!
  96  * \brief a WebSocket server
  97  *
  98  * A server capable of establishing and serving connections
  99  * over WebSocket protocol.
 100  */
 101 class server {
 102     std::vector<server_socket> _listeners;
 103     gate _task_gate;
 104     boost::intrusive::list<connection> _connections;
 105 public:
 106     /*!
 107      * \brief listen for a WebSocket connection on given address
 108      * \param addr address to listen on
 109      */
 110     void listen(socket_address addr);
 111     /*!
 112      * \brief listen for a WebSocket connection on given address with custom options
 113      * \param addr address to listen on
 114      * \param lo custom listen options (\ref listen_options)
 115      */
 116     void listen(socket_address addr, listen_options lo);
 117
 118     /*!
 119      * Stops the server and shuts down all active connections
 120      */
 121     future<> stop();
 122
 123     friend class connection;
 124 protected:
 125     void do_accepts(int which);
 126     future<> do_accept_one(int which);
 127 };
 128
 129 }