go-ethereum/peer.go

package main

import (
  "net"
  "log"
  "github.com/ethereum/ethwire-go"
)

type Peer struct {
  // Server interface
  server      *Server
  // Net connection
  conn        net.Conn
  // Output queue which is used to communicate and handle messages
  outputQueue chan ethwire.InOutMsg
  // Quit channel
  quit        chan bool
}

func NewPeer(conn net.Conn, server *Server) *Peer {
  return &Peer{
    outputQueue:       make(chan ethwire.InOutMsg, 1),  // Buffered chan of 1 is enough
    quit:              make(chan bool),

    server:            server,
    conn:              conn,
  }
}

// Outputs any RLP encoded data to the peer
func (p *Peer) QueueMessage(msgType string, data []byte) {
  p.outputQueue <- ethwire.InOutMsg{MsgType: msgType, Data: data}
}

// Outbound message handler. Outbound messages are handled here
func (p *Peer) HandleOutbound() {
out:
  for {
    select {
    // Main message queue. All outbound messages are processed through here
    case msg := <-p.outputQueue:
      // TODO Message checking and handle accordingly
      err := ethwire.WriteMessage(p.conn, msg)
      if err != nil {
        log.Println(err)

        // Stop the client if there was an error writing to it
        p.Stop()
      }

    // Break out of the for loop if a quit message is posted
    case <- p.quit:
      break out
    }
  }
}

// Inbound handler. Inbound messages are received here and passed to the appropriate methods
func (p *Peer) HandleInbound() {
  defer p.Stop()

out:
  for {
    // Wait for a message from the peer
    msg, err := ethwire.ReadMessage(p.conn)
    if err != nil {
      log.Println(err)

      break out
    }

    // TODO
    data, _ := Decode(msg.Data, 0)
    log.Printf("%s, %s\n", msg.MsgType, data)
  }

  // Notify the out handler we're quiting
  p.quit <- true
}

func (p *Peer) Start() {
  // Run the outbound handler in a new goroutine
  go p.HandleOutbound()
  // Run the inbound handler in a new goroutine
  go p.HandleInbound()
}

func (p *Peer) Stop() {
  p.conn.Close()

  p.quit <- true
}