Derek解读Bytom源码-启动与停止

export BYTOM_DEBUG=debug

./bytomd init --chain_id testnet

./bytomd node --mining --prof_laddr=":8011"

func init() {
	log.SetFormatter(&log.TextFormatter{FullTimestamp: true, DisableColors: true})

	// If environment variable BYTOM_DEBUG is not empty,
	// then add the hook to logrus and set the log level to DEBUG
	if os.Getenv("BYTOM_DEBUG") != "" {
		log.AddHook(ContextHook{})
		log.SetLevel(log.DebugLevel)
	}
}

func main() {
	cmd := cli.PrepareBaseCmd(commands.RootCmd, "TM", os.ExpandEnv(config.DefaultDataDir()))
	cmd.Execute()
}

var (
	config = cfg.DefaultConfig()
)

// Default configurable parameters.
func DefaultConfig() *Config {
	return &Config{
		BaseConfig: DefaultBaseConfig(),  // node基础相关配置
		P2P:        DefaultP2PConfig(),   // p2p网络相关配置
		Wallet:     DefaultWalletConfig(),   // 钱包相关配置
		Auth:       DefaultRPCAuthConfig(),  // 验证相关配置
		Web:        DefaultWebConfig(),   // web相关配置
	}
}

func runNode(cmd *cobra.Command, args []string) error {
	// Create & start node
	n := node.NewNode(config)
	if _, err := n.Start(); err != nil {
		return fmt.Errorf("Failed to start node: %v", err)
	} else {
		log.WithField("nodeInfo", n.SyncManager().Switch().NodeInfo()).Info("Started node")
	}

	// Trap signal, run forever.
	n.RunForever()

	return nil
}

func NewNode(config *cfg.Config) *Node {
	ctx := context.Background()
	initActiveNetParams(config)
	// Get store 初始化txdb数据库
	txDB := dbm.NewDB("txdb", config.DBBackend, config.DBDir())
	store := leveldb.NewStore(txDB)

  // 初始化accesstoken数据库
	tokenDB := dbm.NewDB("accesstoken", config.DBBackend, config.DBDir())
	accessTokens := accesstoken.NewStore(tokenDB)

  // 初始化event事件调度器，也叫任务调度器。一个任务可以被多次调用
	// Make event switch
	eventSwitch := types.NewEventSwitch()
	_, err := eventSwitch.Start()
	if err != nil {
		cmn.Exit(cmn.Fmt("Failed to start switch: %v", err))
	}

  // 初始化交易池
	txPool := protocol.NewTxPool()
	chain, err := protocol.NewChain(store, txPool)
	if err != nil {
		cmn.Exit(cmn.Fmt("Failed to create chain structure: %v", err))
	}

	var accounts *account.Manager = nil
	var assets *asset.Registry = nil
	var wallet *w.Wallet = nil
	var txFeed *txfeed.Tracker = nil

  // 初始化txfeeds数据库
	txFeedDB := dbm.NewDB("txfeeds", config.DBBackend, config.DBDir())
	txFeed = txfeed.NewTracker(txFeedDB, chain)

	if err = txFeed.Prepare(ctx); err != nil {
		log.WithField("error", err).Error("start txfeed")
		return nil
	}

  // 初始化keystore
	hsm, err := pseudohsm.New(config.KeysDir())
	if err != nil {
		cmn.Exit(cmn.Fmt("initialize HSM failed: %v", err))
	}

  // 初始化钱包，默认wallet是开启状态
	if !config.Wallet.Disable {
		walletDB := dbm.NewDB("wallet", config.DBBackend, config.DBDir())
		accounts = account.NewManager(walletDB, chain)
		assets = asset.NewRegistry(walletDB, chain)
		wallet, err = w.NewWallet(walletDB, accounts, assets, hsm, chain)
		if err != nil {
			log.WithField("error", err).Error("init NewWallet")
		}

		// Clean up expired UTXO reservations periodically.
		go accounts.ExpireReservations(ctx, expireReservationsPeriod)
	}
	newBlockCh := make(chan *bc.Hash, maxNewBlockChSize)

  // 初始化网络节点同步管理
	syncManager, _ := netsync.NewSyncManager(config, chain, txPool, newBlockCh)

  // 初始化pprof，pprof用于输出性能指标，需要制定--prof_laddr参数来开启，在文章开头我们已经开启该功能
	// run the profile server
	profileHost := config.ProfListenAddress
	if profileHost != "" {
		// Profiling bytomd programs.see (https://blog.golang.org/profiling-go-programs)
		// go tool pprof http://profileHose/debug/pprof/heap
		go func() {
			http.ListenAndServe(profileHost, nil)
		}()
	}

  // 初始化节点，填充节点所需的所有参数环境
	node := &Node{
		config:       config,
		syncManager:  syncManager,
		evsw:         eventSwitch,
		accessTokens: accessTokens,
		wallet:       wallet,
		chain:        chain,
		txfeed:       txFeed,
		miningEnable: config.Mining,
	}

  // 初始化挖矿
	node.cpuMiner = cpuminer.NewCPUMiner(chain, accounts, txPool, newBlockCh)
	node.miningPool = miningpool.NewMiningPool(chain, accounts, txPool, newBlockCh)

	node.BaseService = *cmn.NewBaseService(nil, "Node", node)

	return node
}

// Lanch web broser or not
func lanchWebBroser() {
	log.Info("Launching System Browser with :", webAddress)
	if err := browser.Open(webAddress); err != nil {
		log.Error(err.Error())
		return
	}
}

func (n *Node) initAndstartApiServer() {
	n.api = api.NewAPI(n.syncManager, n.wallet, n.txfeed, n.cpuMiner, n.miningPool, n.chain, n.config, n.accessTokens)

	listenAddr := env.String("LISTEN", n.config.ApiAddress)
	env.Parse()
	n.api.StartServer(*listenAddr)
}

func (n *Node) OnStart() error {
	if n.miningEnable {
		n.cpuMiner.Start()
	}
	n.syncManager.Start()
	n.initAndstartApiServer()
	if !n.config.Web.Closed {
		lanchWebBroser()
	}

	return nil
}

func TrapSignal(cb func()) {
	c := make(chan os.Signal, 1)
	signal.Notify(c, os.Interrupt, syscall.SIGTERM)
	go func() {
		for sig := range c {
			fmt.Printf("captured %v, exiting...\n", sig)
			if cb != nil {
				cb()
			}
			os.Exit(1)
		}
	}()
	select {}
}

func (n *Node) OnStop() {
	n.BaseService.OnStop()
	if n.miningEnable {
		n.cpuMiner.Stop()
	}
	n.syncManager.Stop()
	log.Info("Stopping Node")
	// TODO: gracefully disconnect from peers.
}