# asio_net

**Repository Path**: bbindong/asio_net

## Basic Information

- **Project Name**: asio_net
- **Description**: No description available
- **Primary Language**: Unknown
- **License**: MIT
- **Default Branch**: main
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2026-05-14
- **Last Updated**: 2026-05-14

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# asio_net

[![Build Status](https://github.com/shuai132/asio_net/workflows/CI/badge.svg)](https://github.com/shuai132/asio_net/actions?workflow=CI)
[![Release](https://img.shields.io/github/release/shuai132/asio_net.svg)](https://github.com/shuai132/asio_net/releases)
[![License](https://img.shields.io/badge/License-MIT-blue.svg)](LICENSE)

a tiny C++14 Async TCP/UDP/RPC/DDS library based on [asio](http://think-async.com/Asio/)
and [rpc_core](https://github.com/shuai132/rpc_core)

## Features

* Header-Only
* TCP/UDP: support auto_pack option for tcp, will ensure packets are complete, just like websocket
* RPC: via socket(with SSL/TLS), domain socket, support c++20 coroutine for asynchronous operations
* DDS: via socket(with SSL/TLS), domain socket
* Service Discovery: based on UDP multicast
* IPv4 and IPv6
* SSL/TLS: depend OpenSSL
* Serial Port
* Automatic reconnection
* Comprehensive unittests

## Requirements

* [asio](http://think-async.com/Asio/)
* [nlohmann/json](https://github.com/nlohmann/json) (for building tests)
* C++14
* Optional: C++20 (for rpc coroutine api, co_await co_call)

## Usage

* clone

```shell
git clone --recurse-submodules https://github.com/shuai132/asio_net.git
```

or

```shell
git clone https://github.com/shuai132/asio_net.git && cd asio_net
git submodule update --init --recursive
```

* build tests

To build the tests, set `ASIO_PATH` to the asio include directory and set
`NLOHMANN_JSON_PATH` to the include directory containing `nlohmann/json.hpp`.

```shell
git clone https://github.com/chriskohlhoff/asio.git -b asio-1-32-0 --depth=1
git clone https://github.com/nlohmann/json.git --depth=1

ASIO_PATH=asio/asio/include NLOHMANN_JSON_PATH=json/include cmake -S . -B build -DCMAKE_BUILD_TYPE=Debug
cmake --build build -j
```

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

### RPC

rpc based on tcp and [rpc_core](https://github.com/shuai132/rpc_core), and also support ipv6 and ssl.
inspect the code for more details [rpc.cpp](test/rpc.cpp)

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

```c++
// client
asio::io_context context;
rpc_client client(context/*, rpc_config*/);
client.on_open = [](const std::shared_ptr<rpc_core::rpc>& rpc) {
  rpc->cmd("cmd")
     ->msg(std::string("hello"))
     ->rsp([](const std::string& data) {
       assert(data == "world");
     })
     ->call();
};
client.on_close = [] {};
client.open("localhost", PORT);
client.run();
```

and, you can create rpc first, for more details: [rpc_config.cpp](test/rpc_config.cpp)

```c++
// server
auto rpc = rpc_core::rpc::create();
rpc->subscribe("cmd", [](const std::string& data) -> std::string {
  assert(data == "hello");
  return "world";
});

asio::io_context context;
rpc_config config;
config.rpc = rpc;
rpc_server server(context, PORT, config);
server.start(true);
```

```c++
// client
auto rpc = rpc_core::rpc::create();
asio::io_context context;
rpc_config config;
config.rpc = rpc;
rpc_client client(context, config);
client.open("localhost", PORT);
client.run();

rpc->cmd("cmd")->msg(std::string("hello"))->call();
// or: rpc->call("cmd", std::string("hello"));
```

and you can use C++20 coroutine:

```c++
// server
rpc->subscribe("cmd", [&](request_response<std::string, std::string> rr) -> asio::awaitable<void> {
  assert(rr->req == "hello");
  asio::steady_timer timer(context);
  timer.expires_after(std::chrono::seconds(1));
  co_await timer.async_wait();
  rr->rsp("world");
}, scheduler_asio_coroutine);

// client
// use C++20 co_await with asio, or you can use custom async implementation, and co_await it!
auto rsp = co_await rpc->cmd("cmd")->msg(std::string("hello"))->co_call<std::string>();
// or: auto rsp = co_await rpc->co_call<std::string>("cmd", std::string("hello"));
assert(rsp.data == "world");
```

inspect the code for more
details: [rpc_s_coroutine.cpp](test/rpc_s_coroutine.cpp)
and [rpc_c_coroutine.cpp](test/rpc_c_coroutine.cpp)

### DDS

```c++
// run a server as daemon
asio::io_context context;
dds_server server(context, PORT);
server.start(true);
```

```c++
// client
asio::io_context context;
dds_client client(context);
client.open("localhost", PORT);
client.subscribe("topic", [](const std::string& data) {
});
client.publish<std::string>("topic", "string/binary");
client.run();
```

### Server Discovery

```c++
// 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();
```

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

### TCP

You can enable automatic handling of packet fragmentation using `tcp_config`.
Subsequent send and receive will be complete data packets.

By default, this feature is disabled.

```c++
// echo server
asio::io_context context;
tcp_server server(context, PORT/*, tcp_config*/);
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);
```

```c++
// echo client
asio::io_context context;
tcp_client client(context/*, tcp_config*/);
client.on_data = [](const std::string& data) {
};
client.on_close = [] {
};
client.open("localhost", PORT);
client.run();
```

### UDP

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

```c++
// 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();
```

### Serial Port

```c++
asio::io_context context;
serial_port serial(context);
serial.on_open = [&] {
  /// set_option
  serial.set_option(asio::serial_port::baud_rate(115200));
  serial.set_option(asio::serial_port::flow_control(asio::serial_port::flow_control::none));
  serial.set_option(asio::serial_port::parity(asio::serial_port::parity::none));
  serial.set_option(asio::serial_port::stop_bits(asio::serial_port::stop_bits::one));
  serial.set_option(asio::serial_port::character_size(asio::serial_port::character_size(8)));

  /// test
  serial.send("hello world");
};
serial.on_data = [](const std::string& data) {
};
serial.on_open_failed = [](std::error_code ec) {
};
serial.on_close = [] {
};
serial.open("/dev/tty.usbserial-xx");
serial.run();
```

# Links

* RPC library for MCU

most MCU not support asio, there is a library can be ported easily: [esp_rpc](https://github.com/shuai132/esp_rpc)