asio_net

a tiny Async TCP/UDP/RPC library based on ASIO and RpcCore

Features

• Simplifies the development of TCP/UDP programs, relying on: ASIO
• Provides RPC implementation based on: RpcCore
• LAN service discovery based on UDP multicast
• Supports domain sockets
• Comprehensive unittests

Options:

• TCP can be configured to automatically handle the problem of packet fragmentation to support the transmission of complete data packets.

• Supports setting the maximum packet length, and will automatically disconnect if exceeded.

Requirements

• C++14
• ASIO

Usage

The following are examples of using each module. For complete unit tests, please refer to the source code: test

• TCP

You can enable automatic handling of packet fragmentation using PackOption::ENABLE. Subsequent send and receive will be complete data packets.

By default, this feature is disabled.

  // echo server
  asio::io_context context;
  tcp_server server(context, PORT/*, PackOption::ENABLE*/);
  server.on_session = [](const std::weak_ptr<tcp_session>& ws) {
    auto session = ws.lock();
    session->on_close = [] {
    };
    session->on_data = [ws](std::string data) {
      ws.lock()->send(std::move(data));
    };
  };
  server.start(true);

  // echo client
  asio::io_context context;
  tcp_client client(context/*, PackOption::ENABLE*/);

  client.on_data = [](const std::string& data) {
  };
  client.on_close = [] {
  };
  client.open("localhost", PORT);
  context.run();

• UDP

  // server
  asio::io_context context;
  udp_server server(context, PORT);
  server.on_data = [](uint8_t* data, size_t size, const udp::endpoint& from) {
  };
  context.run();

  // client
  asio::io_context context;
  udp_client client(context);
  auto endpoint = udp::endpoint(asio::ip::address_v4::from_string("127.0.0.1"), PORT);
  client.send_to("hello", endpoint);
  context.run();

• RPC

  // server
  asio::io_context context;
  rpc_server server(context, PORT);
  server.on_session = [](const std::weak_ptr<rpc_session>& rs) {
    auto session = rs.lock();
    session->on_close = [] {
    };
    session->rpc->subscribe("cmd", [](const RpcCore::String& data) -> RpcCore::String {
      return "world";
    });
  };
  server.start(true);

  // client
  asio::io_context context;
  rpc_client client(context);
  client.on_open = [](const std::shared_ptr<RpcCore::Rpc>& rpc) {
    rpc->cmd("cmd")
        ->msg(RpcCore::String("hello"))
        ->rsp([](const RpcCore::String& data) {
        })
        ->call();
  };
  client.on_close = [] {
  };
  client.open("localhost", PORT);
  context.run();

• Server Discovery

  // receiver
  asio::io_context context;
  server_discovery::receiver receiver(context, [](const std::string& name, const std::string& message) {
    printf("receive: name: %s, message: %s\n", name.c_str(), message.c_str());
  });
  context.run();

  // sender
  asio::io_context context;
  server_discovery::sender sender_ip(context, "ip", "message");
  context.run();

Links

• RPC library for MCU

  most MCU not support asio, there is a library can be ported easily: esp_rpc