Rust蓝牙开发库bluez-async使用指南

简介

bluez-async是一个Rust库，提供了对Linux蓝牙协议栈(BlueZ)的异步支持，使开发者能够高效地进行蓝牙通信开发。它基于Tokio异步运行时，提供了简洁的API来与BlueZ的DBus接口交互。

主要特性

• 完全异步支持(Tokio)
• 类型安全的DBus接口
• 自动处理DBus对象路径和信号
• 支持蓝牙设备发现、连接、服务发现等操作

安装

在Cargo.toml中添加依赖：

[dependencies]
bluez-async = "0.3"
tokio = { version = "1.0", features = ["full"] }

基本使用方法

初始化蓝牙适配器

use bluez_async::BluetoothSession;

#[tokio::main]
async fn main() -> Result<(), eyre::Report> {
    // 创建蓝牙会话
    let (_, session) = BluetoothSession::new().await?;
    
    // 获取默认适配器
    let adapter = session.get_default_adapter().await?;
    println!("使用适配器: {}", adapter.id);
    
    Ok(())
}

扫描蓝牙设备

use bluez_async::{BluetoothEvent, BluetoothSession};
use futures::stream::StreamExt;

#[tokio::main]
async fn main() -> Result<(), eyre::Report> {
    let (sender, session) = BluetoothSession::new().await?;
    let adapter = session.get_default_adapter().await?;
    
    // 开始扫描
    session.start_discovery(&adapter.id).await?;
    
    // 监听设备发现事件
    let mut events = sender.incoming();
    while let Some(event) = events.next().await {
        match event {
            BluetoothEvent::Device { id, address, rssi, .. } => {
                println!("发现设备: {} (地址: {}), 信号强度: {:?}", id, address, rssi);
            }
            _ => {}
        }
    }
    
    Ok(())
}

连接设备并发现服务

use bluez_async::{BluetoothSession, MacAddress};

#[tokio::main]
async fn main() -> Result<(), eyre::Report> {
    let (_, session) = BluetoothSession::new().await?;
    
    // 设备MAC地址
    let device_addr = MacAddress::from([0xAA, 0xBB, 0xCC, 0xDD, 0xEE, 0xFF]);
    
    // 连接设备
    let device = session.get_device_by_address(device_addr).await?;
    session.connect(&device.id).await?;
    
    // 发现服务
    let services = session.get_services(&device.id).await?;
    for service in services {
        println!("服务 UUID: {}", service.uuid);
    }
    
    Ok(())
}

高级用法

读取特征值

use bluez_async::{BluetoothSession, MacAddress, Uuid};

#[tokio::main]
async fn main() -> Result<(), eyre::Report> {
    let (_, session) = BluetoothSession::new().await?;
    let device_addr = MacAddress::from([0xAA, 0xBB, 0xCC, 0xDD, 0xEE, 0xFF]);
    let device = session.get_device_by_address(device_addr).await?;
    
    // 假设我们已经知道特征UUID
    let char_uuid = Uuid::parse_str("00002a00-0000-1000-8000-00805f9b34fb")?;
    
    // 获取特征
    let characteristic = session.get_characteristic_by_uuid(&device.id, char_uuid).await?;
    
    // 读取特征值
    let value = session.read_value(&characteristic.id).await?;
    println!("特征值: {:?}", value);
    
    Ok(())
}

写入特征值

use bluez_async::{BluetoothSession, MacAddress, Uuid};

#[tokio::main]
async fn main() -> Result<(), eyre::Report> {
    let (_, session) = BluetoothSession::new().await?;
    let device_addr = MacAddress::from([0xAA, 0xBB, 0xCC, 0xDD, 0xEE, 0xFF]);
    let device = session.get_device_by_address(device_addr).await?;
    
    let char_uuid = Uuid::parse_str("00002a01-0000-1000-8000-00805f9b34fb")?;
    let characteristic = session.get_characteristic_by_uuid(&device.id, char_uuid).await?;
    
    // 写入特征值
    let data = vec![0x01, 0x02, 0x03];
    session.write_value(&characteristic.id, data).await?;
    
    Ok(())
}

完整示例

下面是一个完整的蓝牙设备扫描和连接示例：

use bluez_async::{BluetoothEvent, BluetoothSession, MacAddress};
use futures::stream::StreamExt;
use std::time::Duration;
use tokio::time::sleep;

#[tokio::main]
async fn main() -> Result<(), eyre::Report> {
    // 1. 初始化蓝牙会话
    let (sender, session) = BluetoothSession::new().await?;
    let adapter = session.get_default_adapter().await?;
    println!("默认蓝牙适配器: {}", adapter.id);

    // 2. 开始扫描设备
    session.start_discovery(&adapter.id).await?;
    println!("开始扫描蓝牙设备...");

    // 3. 监听设备发现事件
    let mut events = sender.incoming();
    let mut target_device = None;
    
    // 扫描10秒
    tokio::select! {
        _ = async {
            sleep(Duration::from_secs(10)).await;
            println!("扫描结束");
        } => {}
        
        device = async {
            while let Some(event) = events.next().await {
                if let BluetoothEvent::Device { id, address, name, rssi, .. } = event {
                    println!("发现设备: {} (地址: {}), 名称: {:?}, 信号强度: {:?}", 
                           id, address, name, rssi);
                    
                    // 假设我们要连接名为"MyDevice"的设备
                    if name.as_deref() == Some("MyDevice") {
                        target_device = Some((id, address));
                        break;
                    }
                }
            }
        } => {}
    }

    // 4. 停止扫描
    session.stop_discovery(&adapter.id).await?;

    // 5. 连接目标设备
    if let Some((device_id, address)) = target_device {
        println!("尝试连接设备: {}", address);
        
        // 连接设备
        session.connect(&device_id).await?;
        println!("设备已连接");
        
        // 发现服务
        let services = session.get_services(&device_id).await?;
        println!("发现{}个服务:", services.len());
        
        for service in services {
            println!("服务 UUID: {}", service.uuid);
        }
    } else {
        println!("未找到目标设备");
    }

    Ok(())
}

注意事项

1. 需要Linux系统和BlueZ蓝牙协议栈
2. 需要DBus系统服务正常运行
3. 程序运行时需要适当的权限(通常需要root或加入bluetooth组)
4. 某些操作可能需要先停止扫描才能执行

bluez-async库为Rust开发者提供了高效、类型安全的方式来与Linux蓝牙设备交互，特别适合需要高性能蓝牙通信的应用场景。