github.com/linapex/ethereum-go-chinese@v0.0.0-20190316121929-f8b7a73c3fa1/cmd/geth/config.go

//<developer>
//    <name>linapex 曹一峰</name>
//    <email>linapex@163.com</email>
//    <wx>superexc</wx>
//    <qqgroup>128148617</qqgroup>
//    <url>https://jsq.ink</url>
//    <role>pku engineer</role>
//    <date>2019-03-16 19:16:32</date>
//</624450068384059392>


package main

import (
	"bufio"
	"errors"
	"fmt"
	"math/big"
	"os"
	"reflect"
	"unicode"

	cli "gopkg.in/urfave/cli.v1"

	"github.com/ethereum/go-ethereum/cmd/utils"
	"github.com/ethereum/go-ethereum/dashboard"
	"github.com/ethereum/go-ethereum/eth"
	"github.com/ethereum/go-ethereum/node"
	"github.com/ethereum/go-ethereum/params"
	whisper "github.com/ethereum/go-ethereum/whisper/whisperv6"
	"github.com/naoina/toml"
)

var (
	dumpConfigCommand = cli.Command{
		Action:      utils.MigrateFlags(dumpConfig),
		Name:        "dumpconfig",
		Usage:       "Show configuration values",
		ArgsUsage:   "",
		Flags:       append(append(nodeFlags, rpcFlags...), whisperFlags...),
		Category:    "MISCELLANEOUS COMMANDS",
		Description: `The dumpconfig command shows configuration values.`,
	}

	configFileFlag = cli.StringFlag{
		Name:  "config",
		Usage: "TOML configuration file",
	}
)

//这些设置确保toml键使用与go struct字段相同的名称。
var tomlSettings = toml.Config{
	NormFieldName: func(rt reflect.Type, key string) string {
		return key
	},
	FieldToKey: func(rt reflect.Type, field string) string {
		return field
	},
	MissingField: func(rt reflect.Type, field string) error {
		link := ""
		if unicode.IsUpper(rune(rt.Name()[0])) && rt.PkgPath() != "main" {
link = fmt.Sprintf(", see https://godoc.org/%s%s，用于可用字段“，rt.pkgpath（），rt.name（））
		}
		return fmt.Errorf("field '%s' is not defined in %s%s", field, rt.String(), link)
	},
}

type ethstatsConfig struct {
	URL string `toml:",omitempty"`
}

type gethConfig struct {
	Eth       eth.Config
	Shh       whisper.Config
	Node      node.Config
	Ethstats  ethstatsConfig
	Dashboard dashboard.Config
}

func loadConfig(file string, cfg *gethConfig) error {
	f, err := os.Open(file)
	if err != nil {
		return err
	}
	defer f.Close()

	err = tomlSettings.NewDecoder(bufio.NewReader(f)).Decode(cfg)
//将文件名添加到具有行号的错误中。
	if _, ok := err.(*toml.LineError); ok {
		err = errors.New(file + ", " + err.Error())
	}
	return err
}

func defaultNodeConfig() node.Config {
	cfg := node.DefaultConfig
	cfg.Name = clientIdentifier
	cfg.Version = params.VersionWithCommit(gitCommit)
	cfg.HTTPModules = append(cfg.HTTPModules, "eth", "shh")
	cfg.WSModules = append(cfg.WSModules, "eth", "shh")
	cfg.IPCPath = "geth.ipc"
	return cfg
}

func makeConfigNode(ctx *cli.Context) (*node.Node, gethConfig) {
//加载默认值。
	cfg := gethConfig{
		Eth:       eth.DefaultConfig,
		Shh:       whisper.DefaultConfig,
		Node:      defaultNodeConfig(),
		Dashboard: dashboard.DefaultConfig,
	}

//加载配置文件。
	if file := ctx.GlobalString(configFileFlag.Name); file != "" {
		if err := loadConfig(file, &cfg); err != nil {
			utils.Fatalf("%v", err)
		}
	}

//应用标志。
	utils.SetNodeConfig(ctx, &cfg.Node)
	stack, err := node.New(&cfg.Node)
	if err != nil {
		utils.Fatalf("Failed to create the protocol stack: %v", err)
	}
	utils.SetEthConfig(ctx, stack, &cfg.Eth)
	if ctx.GlobalIsSet(utils.EthStatsURLFlag.Name) {
		cfg.Ethstats.URL = ctx.GlobalString(utils.EthStatsURLFlag.Name)
	}

	utils.SetShhConfig(ctx, stack, &cfg.Shh)
	utils.SetDashboardConfig(ctx, &cfg.Dashboard)

	return stack, cfg
}

//如果设置了其中一个耳语标志，则EnableShipper返回true。
func enableWhisper(ctx *cli.Context) bool {
	for _, flag := range whisperFlags {
		if ctx.GlobalIsSet(flag.GetName()) {
			return true
		}
	}
	return false
}

func makeFullNode(ctx *cli.Context) *node.Node {
	stack, cfg := makeConfigNode(ctx)
	if ctx.GlobalIsSet(utils.ConstantinopleOverrideFlag.Name) {
		cfg.Eth.ConstantinopleOverride = new(big.Int).SetUint64(ctx.GlobalUint64(utils.ConstantinopleOverrideFlag.Name))
	}
	utils.RegisterEthService(stack, &cfg.Eth)

	if ctx.GlobalBool(utils.DashboardEnabledFlag.Name) {
		utils.RegisterDashboardService(stack, &cfg.Dashboard, gitCommit)
	}
//必须通过指定至少1个耳语标志或在DEV模式下显式启用耳语
	shhEnabled := enableWhisper(ctx)
	shhAutoEnabled := !ctx.GlobalIsSet(utils.WhisperEnabledFlag.Name) && ctx.GlobalIsSet(utils.DeveloperFlag.Name)
	if shhEnabled || shhAutoEnabled {
		if ctx.GlobalIsSet(utils.WhisperMaxMessageSizeFlag.Name) {
			cfg.Shh.MaxMessageSize = uint32(ctx.Int(utils.WhisperMaxMessageSizeFlag.Name))
		}
		if ctx.GlobalIsSet(utils.WhisperMinPOWFlag.Name) {
			cfg.Shh.MinimumAcceptedPOW = ctx.Float64(utils.WhisperMinPOWFlag.Name)
		}
		if ctx.GlobalIsSet(utils.WhisperRestrictConnectionBetweenLightClientsFlag.Name) {
			cfg.Shh.RestrictConnectionBetweenLightClients = true
		}
		utils.RegisterShhService(stack, &cfg.Shh)
	}

//如果需要，添加ethereum stats守护进程。
	if cfg.Ethstats.URL != "" {
		utils.RegisterEthStatsService(stack, cfg.Ethstats.URL)
	}
	return stack
}

//dumpconfig是dumpconfig命令。
func dumpConfig(ctx *cli.Context) error {
	_, cfg := makeConfigNode(ctx)
	comment := ""

	if cfg.Eth.Genesis != nil {
		cfg.Eth.Genesis = nil
		comment += "# Note: this config doesn't contain the genesis block.\n\n"
	}

	out, err := tomlSettings.Marshal(&cfg)
	if err != nil {
		return err
	}

	dump := os.Stdout
	if ctx.NArg() > 0 {
		dump, err = os.OpenFile(ctx.Args().Get(0), os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0644)
		if err != nil {
			return err
		}
		defer dump.Close()
	}
	dump.WriteString(comment)
	dump.Write(out)

	return nil
}