Rust BP-Relayers插件库的使用：高效区块链中继层解决方案

完整示例Demo

下面是一个完整的BP-Relayers使用示例，展示了如何初始化中继器、处理事件和发送跨链消息：

use bp_relayers::{
    RelayerBuilder, 
    NetworkConfig, 
    Event, 
    EventHandler, 
    CrossChainMessage, 
    TargetChain,
    RelayerError
};
use async_trait::async_trait;

#[tokio::main]
async fn main() -> Result<(), RelayerError> {
    // 1. 初始化中继器
    let config = NetworkConfig::default()
        .with_chain_id("ethereum_mainnet")
        .with_rpc_url("https://mainnet.infura.io/v3/YOUR-PROJECT-ID")
        .with_polling_interval(3000); // 3秒轮询间隔
    
    let relayer = RelayerBuilder::new()
        .add_network(config)
        .enable_compression(CompressionAlgorithm::Zstd) // 启用压缩
        .build()
        .await?;

    // 2. 注册事件处理器
    relayer.register_handler(Box::new(MyEventHandler)).await;

    // 3. 发送跨链消息
    let message = CrossChainMessage::new(
        "0x742d35Cc6634C0532925a3b844Bc454e4438f44e".to_string(),
        TargetChain::Polkadot,
        vec![0x12, 0x34, 0x56], // 消息负载
    );
    
    match relayer.send_message(message).await {
        Ok(receipt) => println!("Message sent successfully: {:?}", receipt),
        Err(e) => eprintln!("Failed to send message: {:?}", e),
    }

    Ok(())
}

// 自定义事件处理器
struct MyEventHandler;

#[async_trait]
impl EventHandler for MyEventHandler {
    async fn handle(&self, event: Event) {
        match event {
            Event::BlockHeader(header) => {
                println!("New block header received:");
                println!("Number: {}", header.number);
                println!("Hash: {:?}", header.hash);
                // 这里可以添加处理区块头的业务逻辑
            }
            Event::CrossChainMessage(msg) => {
                println!("Cross-chain message received:");
                println!("Sender: {}", msg.sender());
                println!("Target chain: {:?}", msg.target_chain());
                println!("Payload length: {} bytes", msg.payload().len());
                // 这里可以添加处理跨链消息的业务逻辑
            }
            _ => {}
        }
    }
}

// 自定义验证规则
struct EthAddressValidation;

impl ValidationRule for EthAddressValidation {
    fn validate(&self, message: &CrossChainMessage) -> bool {
        // 验证发送者地址是以0x开头的42个字符(20字节地址)
        message.sender().starts_with("0x") 
            && message.sender().len() == 42
            && message.payload().len() > 0
    }
}

示例项目完整结构

my_relayer_project/
├── Cargo.toml
└── src/
    ├── main.rs          # 主程序入口
    ├── config.rs        # 配置文件
    ├── handlers/
    │   ├── mod.rs       # 处理器模块
    │   └── eth_handler.rs # 以太坊事件处理器
    └── validations/
        ├── mod.rs       # 验证模块
        └── address_validation.rs # 地址验证规则

config.rs 示例

use bp_relayers::NetworkConfig;

pub fn get_eth_config() -> NetworkConfig {
    NetworkConfig::new("ethereum_mainnet")
        .with_rpc_url("https://mainnet.infura.io/v3/YOUR-PROJECT-ID")
        .with_polling_interval(3000)
}

pub fn get_polkadot_config() -> NetworkConfig {
    NetworkConfig::new("polkadot_mainnet")
        .with_rpc_url("wss://rpc.polkadot.io")
}

handlers/eth_handler.rs 示例

use bp_relayers::{Event, EventHandler};
use async_trait::async_trait;

pub struct EthEventHandler;

#[async_trait]
impl EventHandler for EthEventHandler {
    async fn handle(&self, event: Event) {
        if let Event::BlockHeader(header) = event {
            // 专门处理以太坊区块头
            println!("ETH Block #{}: {:?}", header.number, header.hash);
        }
    }
}

validations/address_validation.rs 示例

use bp_relayers::{ValidationRule, CrossChainMessage};

pub struct AddressValidation;

impl ValidationRule for AddressValidation {
    fn validate(&self, message: &CrossChainMessage) -> bool {
        // 验证地址格式和消息负载
        message.sender().starts_with("0x") 
            && message.sender().len() == 42
            && !message.payload().is_empty()
    }
}

这个完整示例展示了如何:

1. 初始化配置多链中继器
2. 实现自定义事件处理器
3. 添加消息验证规则
4. 发送跨链消息
5. 处理各种错误情况

您可以根据实际需求扩展这个基础框架，添加更多区块链网络支持或自定义业务逻辑。