P2P网络传输与区块链核心业务之间产生联系的枢纽，事件处理、交互。

ChainToPoolAndNetAdapter

/// Implementation of the ChainAdapter for the network. Gets notified when the
/// blockchain accepted a new block, asking the pool to update its state and
/// the network to broadcast the block
pub struct ChainToPoolAndNetAdapter {
    tx_pool: Arc<RwLock<pool::TransactionPool<PoolToChainAdapter>>>,
    peers: OneTime<Weak<p2p::Peers>>,
}

PoolToNetAdapter

/// Adapter between the transaction pool and the network, to relay
/// transactions that have been accepted.
pub struct PoolToNetAdapter {
    peers: OneTime<Weak<p2p::Peers>>,
}

PoolToChainAdapter

/// Implements the view of the blockchain required by the TransactionPool to
/// operate. Mostly needed to break any direct lifecycle or implementation
/// dependency between the pool and the chain.
pub struct PoolToChainAdapter {
    chain: OneTime<Weak<chain::Chain>>,
}

NetToChainAdapter

/// Implementation of the NetAdapter for the blockchain. Gets notified when new
/// blocks and transactions are received and forwards to the chain and pool
/// implementations.
pub struct NetToChainAdapter {
    currently_syncing: Arc<AtomicBool>,
    archive_mode: bool,
    chain: Weak<chain::Chain>,
    tx_pool: Arc<RwLock<pool::TransactionPool<PoolToChainAdapter>>>,
    peers: OneTime<Weak<p2p::Peers>>,
    config: ServerConfig,
}

怎么连接的？

• chain 有 pub trait ChainAdapter 对应 servers 有 impl ChainAdapter for ChainToPoolAndNetAdapter

• p2p 有 pub trait ChainAdapter: Sync + Send 对应 servers 有 impl p2p::ChainAdapter for NetToChainAdapter

• pool 有 pub trait PoolAdapter: Send + Sync 对应 servers 有 impl pool::PoolAdapter for PoolToNetAdapter

• pool 有 pub trait BlockChain 对应 servers 有 impl pool::BlockChain for PoolToChainAdapter