go-ethereum/server.go

package main

import (
	"container/list"
	"github.com/ethereum/ethdb-go"
	"github.com/ethereum/ethutil-go"
	"log"
	"net"
	_ "time"
)

type Server struct {
	// Channel for shutting down the server
	shutdownChan chan bool
	// DB interface
	db *ethdb.LDBDatabase
	// Block manager for processing new blocks and managing the block chain
	blockManager *BlockManager
	// Peers (NYI)
	peers *list.List
}

func NewServer() (*Server, error) {
	db, err := ethdb.NewLDBDatabase()
	if err != nil {
		return nil, err
	}

	ethutil.SetConfig(db)

	server := &Server{
		shutdownChan: make(chan bool),
		blockManager: NewBlockManager(),
		db:           db,
		peers:        list.New(),
	}

	return server, nil
}

func (s *Server) AddPeer(conn net.Conn) {
	peer := NewPeer(conn, s)
	s.peers.PushBack(peer)
	peer.Start()

	log.Println("Peer connected ::", conn.RemoteAddr())
}

func (s *Server) ConnectToPeer(addr string) error {
	conn, err := net.Dial("tcp", addr)

	if err != nil {
		return err
	}

	peer := NewPeer(conn, s)
	s.peers.PushBack(peer)
	peer.Start()

	log.Println("Connected to peer ::", conn.RemoteAddr())

	return nil
}

func (s *Server) Broadcast(msgType string, data []byte) {
	for e := s.peers.Front(); e != nil; e = e.Next() {
		if peer, ok := e.Value.(*Peer); ok {
			peer.QueueMessage(msgType, data)
		}
	}
}

// Start the server
func (s *Server) Start() {
	// For now this function just blocks the main thread
	ln, err := net.Listen("tcp", ":12345")
	if err != nil {
		log.Fatal(err)
	}

	go func() {
		for {
			conn, err := ln.Accept()
			if err != nil {
				log.Println(err)
				continue
			}

			go s.AddPeer(conn)
		}
	}()

	// TMP
	//go func() {
	//  for {
	//    s.Broadcast("block", Encode("blockdata"))
	//
	//      time.Sleep(100 * time.Millisecond)
	//    }
	//  }()
}

func (s *Server) Stop() {
	// Close the database
	defer s.db.Close()

	// Loop thru the peers and close them (if we had them)
	for e := s.peers.Front(); e != nil; e = e.Next() {
		if peer, ok := e.Value.(*Peer); ok {
			peer.Stop()
		}
	}

	s.shutdownChan <- true
}

// This function will wait for a shutdown and resumes main thread execution
func (s *Server) WaitForShutdown() {
	<-s.shutdownChan
}