github.com/linapex/ethereum-dpos-chinese@v0.0.0-20190316121959-b78b3a4a1ece/cmd/faucet/faucet.go (about)

     1  
     2  //<developer>
     3  //    <name>linapex 曹一峰</name>
     4  //    <email>linapex@163.com</email>
     5  //    <wx>superexc</wx>
     6  //    <qqgroup>128148617</qqgroup>
     7  //    <url>https://jsq.ink</url>
     8  //    <role>pku engineer</role>
     9  //    <date>2019-03-16 12:09:28</date>
    10  //</624342590287777792>
    11  
    12  
    13  //
    14  package main
    15  
    16  //go:generate go bindata-nometadata-o website.go水龙头.html
    17  //go:生成gofmt-w-s网站。go
    18  
    19  import (
    20  	"bytes"
    21  	"context"
    22  	"encoding/json"
    23  	"errors"
    24  	"flag"
    25  	"fmt"
    26  	"html/template"
    27  	"io/ioutil"
    28  	"math"
    29  	"math/big"
    30  	"net/http"
    31  	"net/url"
    32  	"os"
    33  	"path/filepath"
    34  	"regexp"
    35  	"strconv"
    36  	"strings"
    37  	"sync"
    38  	"time"
    39  
    40  	"github.com/ethereum/go-ethereum/accounts"
    41  	"github.com/ethereum/go-ethereum/accounts/keystore"
    42  	"github.com/ethereum/go-ethereum/common"
    43  	"github.com/ethereum/go-ethereum/core"
    44  	"github.com/ethereum/go-ethereum/core/types"
    45  	"github.com/ethereum/go-ethereum/eth"
    46  	"github.com/ethereum/go-ethereum/eth/downloader"
    47  	"github.com/ethereum/go-ethereum/ethclient"
    48  	"github.com/ethereum/go-ethereum/ethstats"
    49  	"github.com/ethereum/go-ethereum/les"
    50  	"github.com/ethereum/go-ethereum/log"
    51  	"github.com/ethereum/go-ethereum/node"
    52  	"github.com/ethereum/go-ethereum/p2p"
    53  	"github.com/ethereum/go-ethereum/p2p/discover"
    54  	"github.com/ethereum/go-ethereum/p2p/discv5"
    55  	"github.com/ethereum/go-ethereum/p2p/nat"
    56  	"github.com/ethereum/go-ethereum/params"
    57  	"golang.org/x/net/websocket"
    58  )
    59  
    60  
    61  
    62  
    63  var (
    64  	genesisFlag = flag.String("genesis", "", "Genesis json file to seed the chain with")
    65  	apiPortFlag = flag.Int("apiport", 8080, "Listener port for the HTTP API connection")
    66  	ethPortFlag = flag.Int("ethport", 30303, "Listener port for the devp2p connection")
    67  	bootFlag    = flag.String("bootnodes", "", "Comma separated bootnode enode URLs to seed with")
    68  	netFlag     = flag.Uint64("network", 0, "Network ID to use for the Ethereum protocol")
    69  	statsFlag   = flag.String("ethstats", "", "Ethstats network monitoring auth string")
    70  
    71  	netnameFlag = flag.String("faucet.name", "", "Network name to assign to the faucet")
    72  	payoutFlag  = flag.Int("faucet.amount", 1, "Number of Ethers to pay out per user request")
    73  	minutesFlag = flag.Int("faucet.minutes", 1440, "Number of minutes to wait between funding rounds")
    74  	tiersFlag   = flag.Int("faucet.tiers", 3, "Number of funding tiers to enable (x3 time, x2.5 funds)")
    75  
    76  	accJSONFlag = flag.String("account.json", "", "Key json file to fund user requests with")
    77  	accPassFlag = flag.String("account.pass", "", "Decryption password to access faucet funds")
    78  
    79  	captchaToken  = flag.String("captcha.token", "", "Recaptcha site key to authenticate client side")
    80  	captchaSecret = flag.String("captcha.secret", "", "Recaptcha secret key to authenticate server side")
    81  
    82  	noauthFlag = flag.Bool("noauth", false, "Enables funding requests without authentication")
    83  	logFlag    = flag.Int("loglevel", 3, "Log level to use for Ethereum and the faucet")
    84  )
    85  
    86  var (
    87  	ether = new(big.Int).Exp(big.NewInt(10), big.NewInt(18), nil)
    88  )
    89  
    90  func main() {
    91  //分析标志并设置记录器以打印所请求的所有内容
    92  	flag.Parse()
    93  	log.Root().SetHandler(log.LvlFilterHandler(log.Lvl(*logFlag), log.StreamHandler(os.Stderr, log.TerminalFormat(true))))
    94  
    95  //构建支出层
    96  	amounts := make([]string, *tiersFlag)
    97  	periods := make([]string, *tiersFlag)
    98  	for i := 0; i < *tiersFlag; i++ {
    99  //计算下一层的金额并格式化
   100  		amount := float64(*payoutFlag) * math.Pow(2.5, float64(i))
   101  		amounts[i] = fmt.Sprintf("%s Ethers", strconv.FormatFloat(amount, 'f', -1, 64))
   102  		if amount == 1 {
   103  			amounts[i] = strings.TrimSuffix(amounts[i], "s")
   104  		}
   105  //计算下一层的期间并设置其格式
   106  		period := *minutesFlag * int(math.Pow(3, float64(i)))
   107  		periods[i] = fmt.Sprintf("%d mins", period)
   108  		if period%60 == 0 {
   109  			period /= 60
   110  			periods[i] = fmt.Sprintf("%d hours", period)
   111  
   112  			if period%24 == 0 {
   113  				period /= 24
   114  				periods[i] = fmt.Sprintf("%d days", period)
   115  			}
   116  		}
   117  		if period == 1 {
   118  			periods[i] = strings.TrimSuffix(periods[i], "s")
   119  		}
   120  	}
   121  //加载并呈现水龙头网站
   122  	tmpl, err := Asset("faucet.html")
   123  	if err != nil {
   124  		log.Crit("Failed to load the faucet template", "err", err)
   125  	}
   126  	website := new(bytes.Buffer)
   127  	err = template.Must(template.New("").Parse(string(tmpl))).Execute(website, map[string]interface{}{
   128  		"Network":   *netnameFlag,
   129  		"Amounts":   amounts,
   130  		"Periods":   periods,
   131  		"Recaptcha": *captchaToken,
   132  		"NoAuth":    *noauthFlag,
   133  	})
   134  	if err != nil {
   135  		log.Crit("Failed to render the faucet template", "err", err)
   136  	}
   137  //加载并分析用户请求的Genesis块
   138  	blob, err := ioutil.ReadFile(*genesisFlag)
   139  	if err != nil {
   140  		log.Crit("Failed to read genesis block contents", "genesis", *genesisFlag, "err", err)
   141  	}
   142  	genesis := new(core.Genesis)
   143  	if err = json.Unmarshal(blob, genesis); err != nil {
   144  		log.Crit("Failed to parse genesis block json", "err", err)
   145  	}
   146  //将bootnode转换为内部enode表示形式
   147  	var enodes []*discv5.Node
   148  	for _, boot := range strings.Split(*bootFlag, ",") {
   149  		if url, err := discv5.ParseNode(boot); err == nil {
   150  			enodes = append(enodes, url)
   151  		} else {
   152  			log.Error("Failed to parse bootnode URL", "url", boot, "err", err)
   153  		}
   154  	}
   155  //加载帐户密钥并解密其密码
   156  	if blob, err = ioutil.ReadFile(*accPassFlag); err != nil {
   157  		log.Crit("Failed to read account password contents", "file", *accPassFlag, "err", err)
   158  	}
   159  	pass := string(blob)
   160  
   161  	ks := keystore.NewKeyStore(filepath.Join(os.Getenv("HOME"), ".faucet", "keys"), keystore.StandardScryptN, keystore.StandardScryptP)
   162  	if blob, err = ioutil.ReadFile(*accJSONFlag); err != nil {
   163  		log.Crit("Failed to read account key contents", "file", *accJSONFlag, "err", err)
   164  	}
   165  	acc, err := ks.Import(blob, pass, pass)
   166  	if err != nil {
   167  		log.Crit("Failed to import faucet signer account", "err", err)
   168  	}
   169  	ks.Unlock(acc, pass)
   170  
   171  //组装并启动水龙头照明服务
   172  	faucet, err := newFaucet(genesis, *ethPortFlag, enodes, *netFlag, *statsFlag, ks, website.Bytes())
   173  	if err != nil {
   174  		log.Crit("Failed to start faucet", "err", err)
   175  	}
   176  	defer faucet.close()
   177  
   178  	if err := faucet.listenAndServe(*apiPortFlag); err != nil {
   179  		log.Crit("Failed to launch faucet API", "err", err)
   180  	}
   181  }
   182  
   183  //请求表示已接受的资金请求。
   184  type request struct {
   185  Avatar  string             `json:"avatar"`  //使用户界面更美好的虚拟人物URL
   186  Account common.Address     `json:"account"` //正在资助以太坊地址
   187  Time    time.Time          `json:"time"`    //接受请求时的时间戳
   188  Tx      *types.Transaction `json:"tx"`      //为账户提供资金的交易
   189  }
   190  
   191  //
   192  type faucet struct {
   193  config *params.ChainConfig //签名的链配置
   194  stack  *node.Node          //以太坊协议栈
   195  client *ethclient.Client   //
   196  index  []byte              //在网上提供的索引页
   197  
   198  keystore *keystore.KeyStore //包含单个签名者的密钥库
   199  account  accounts.Account   //帐户资金用户水龙头请求
   200  nonce    uint64             //水龙头的当前挂起时间
   201  price    *big.Int           //发行资金的当前天然气价格
   202  
   203  conns    []*websocket.Conn    //当前活动的WebSocket连接
   204  timeouts map[string]time.Time //用户历史及其资金超时
   205  reqs     []*request           //当前待定的资金请求
   206  update   chan struct{}        //通道到信号请求更新
   207  
   208  lock sync.RWMutex //锁保护水龙头内部
   209  }
   210  
   211  func newFaucet(genesis *core.Genesis, port int, enodes []*discv5.Node, network uint64, stats string, ks *keystore.KeyStore, index []byte) (*faucet, error) {
   212  //组装原始devp2p协议栈
   213  	stack, err := node.New(&node.Config{
   214  		Name:    "geth",
   215  		Version: params.VersionWithMeta,
   216  		DataDir: filepath.Join(os.Getenv("HOME"), ".faucet"),
   217  		P2P: p2p.Config{
   218  			NAT:              nat.Any(),
   219  			NoDiscovery:      true,
   220  			DiscoveryV5:      true,
   221  			ListenAddr:       fmt.Sprintf(":%d", port),
   222  			MaxPeers:         25,
   223  			BootstrapNodesV5: enodes,
   224  		},
   225  	})
   226  	if err != nil {
   227  		return nil, err
   228  	}
   229  //组装以太坊Light客户端协议
   230  	if err := stack.Register(func(ctx *node.ServiceContext) (node.Service, error) {
   231  		cfg := eth.DefaultConfig
   232  		cfg.SyncMode = downloader.LightSync
   233  		cfg.NetworkId = network
   234  		cfg.Genesis = genesis
   235  		return les.New(ctx, &cfg)
   236  	}); err != nil {
   237  		return nil, err
   238  	}
   239  //组装ethstats监视和报告服务'
   240  	if stats != "" {
   241  		if err := stack.Register(func(ctx *node.ServiceContext) (node.Service, error) {
   242  			var serv *les.LightEthereum
   243  			ctx.Service(&serv)
   244  			return ethstats.New(stats, nil, serv)
   245  		}); err != nil {
   246  			return nil, err
   247  		}
   248  	}
   249  //启动客户机并确保它连接到引导节点
   250  	if err := stack.Start(); err != nil {
   251  		return nil, err
   252  	}
   253  	for _, boot := range enodes {
   254  		old, _ := discover.ParseNode(boot.String())
   255  		stack.Server().AddPeer(old)
   256  	}
   257  //附加到客户端并检索有趣的元数据
   258  	api, err := stack.Attach()
   259  	if err != nil {
   260  		stack.Stop()
   261  		return nil, err
   262  	}
   263  	client := ethclient.NewClient(api)
   264  
   265  	return &faucet{
   266  		config:   genesis.Config,
   267  		stack:    stack,
   268  		client:   client,
   269  		index:    index,
   270  		keystore: ks,
   271  		account:  ks.Accounts()[0],
   272  		timeouts: make(map[string]time.Time),
   273  		update:   make(chan struct{}, 1),
   274  	}, nil
   275  }
   276  
   277  //关闭会终止以太坊连接并将水龙头拆下。
   278  func (f *faucet) close() error {
   279  	return f.stack.Stop()
   280  }
   281  
   282  //listenandserve注册水龙头的HTTP处理程序并启动它。
   283  //服务用户资金请求。
   284  func (f *faucet) listenAndServe(port int) error {
   285  	go f.loop()
   286  
   287  	http.HandleFunc("/", f.webHandler)
   288  	http.Handle("/api", websocket.Handler(f.apiHandler))
   289  
   290  	return http.ListenAndServe(fmt.Sprintf(":%d", port), nil)
   291  }
   292  
   293  //WebHandler处理所有非API请求,只需扁平化并返回
   294  //水龙头网站。
   295  func (f *faucet) webHandler(w http.ResponseWriter, r *http.Request) {
   296  	w.Write(f.index)
   297  }
   298  
   299  //apiHandler处理乙醚授权和事务状态的请求。
   300  func (f *faucet) apiHandler(conn *websocket.Conn) {
   301  //开始跟踪连接并在末尾放置
   302  	defer conn.Close()
   303  
   304  	f.lock.Lock()
   305  	f.conns = append(f.conns, conn)
   306  	f.lock.Unlock()
   307  
   308  	defer func() {
   309  		f.lock.Lock()
   310  		for i, c := range f.conns {
   311  			if c == conn {
   312  				f.conns = append(f.conns[:i], f.conns[i+1:]...)
   313  				break
   314  			}
   315  		}
   316  		f.lock.Unlock()
   317  	}()
   318  //从网络收集初始统计数据以进行报告
   319  	var (
   320  		head    *types.Header
   321  		balance *big.Int
   322  		nonce   uint64
   323  		err     error
   324  	)
   325  	for {
   326  //尝试检索统计信息,可能在没有水龙头连接时出错。
   327  		ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
   328  		head, err = f.client.HeaderByNumber(ctx, nil)
   329  		if err == nil {
   330  			balance, err = f.client.BalanceAt(ctx, f.account.Address, head.Number)
   331  			if err == nil {
   332  				nonce, err = f.client.NonceAt(ctx, f.account.Address, nil)
   333  			}
   334  		}
   335  		cancel()
   336  
   337  //如果状态检索失败,请稍等片刻,然后重试。
   338  		if err != nil {
   339  			if err = sendError(conn, errors.New("Faucet offline: "+err.Error())); err != nil {
   340  				log.Warn("Failed to send faucet error to client", "err", err)
   341  				return
   342  			}
   343  			time.Sleep(3 * time.Second)
   344  			continue
   345  		}
   346  //已成功报告初始状态,继续用户交互
   347  		break
   348  	}
   349  //发送初始数据和最新标题
   350  	if err = send(conn, map[string]interface{}{
   351  		"funds":    balance.Div(balance, ether),
   352  		"funded":   nonce,
   353  		"peers":    f.stack.Server().PeerCount(),
   354  		"requests": f.reqs,
   355  	}, 3*time.Second); err != nil {
   356  		log.Warn("Failed to send initial stats to client", "err", err)
   357  		return
   358  	}
   359  	if err = send(conn, head, 3*time.Second); err != nil {
   360  		log.Warn("Failed to send initial header to client", "err", err)
   361  		return
   362  	}
   363  //继续从WebSocket读取请求,直到连接断开
   364  	for {
   365  //获取下一个融资请求并根据Github进行验证
   366  		var msg struct {
   367  			URL     string `json:"url"`
   368  			Tier    uint   `json:"tier"`
   369  			Captcha string `json:"captcha"`
   370  		}
   371  		if err = websocket.JSON.Receive(conn, &msg); err != nil {
   372  			return
   373  		}
   374  if !*noauthFlag && !strings.HasPrefix(msg.URL, "https://
   375  !strings.HasPrefix(msg.URL, "https://另外,google.com/“)&&!strings.hasPrefix(msg.url,“https://www.facebook.com/”)
   376  			if err = sendError(conn, errors.New("URL doesn't link to supported services")); err != nil {
   377  				log.Warn("Failed to send URL error to client", "err", err)
   378  				return
   379  			}
   380  			continue
   381  		}
   382  		if msg.Tier >= uint(*tiersFlag) {
   383  			if err = sendError(conn, errors.New("Invalid funding tier requested")); err != nil {
   384  				log.Warn("Failed to send tier error to client", "err", err)
   385  				return
   386  			}
   387  			continue
   388  		}
   389  		log.Info("Faucet funds requested", "url", msg.URL, "tier", msg.Tier)
   390  
   391  //如果验证码验证被启用,确保我们没有处理机器人
   392  		if *captchaToken != "" {
   393  			form := url.Values{}
   394  			form.Add("secret", *captchaSecret)
   395  			form.Add("response", msg.Captcha)
   396  
   397  res, err := http.PostForm("https://www.google.com/recaptcha/api/siteverify“,表单)
   398  			if err != nil {
   399  				if err = sendError(conn, err); err != nil {
   400  					log.Warn("Failed to send captcha post error to client", "err", err)
   401  					return
   402  				}
   403  				continue
   404  			}
   405  			var result struct {
   406  				Success bool            `json:"success"`
   407  				Errors  json.RawMessage `json:"error-codes"`
   408  			}
   409  			err = json.NewDecoder(res.Body).Decode(&result)
   410  			res.Body.Close()
   411  			if err != nil {
   412  				if err = sendError(conn, err); err != nil {
   413  					log.Warn("Failed to send captcha decode error to client", "err", err)
   414  					return
   415  				}
   416  				continue
   417  			}
   418  			if !result.Success {
   419  				log.Warn("Captcha verification failed", "err", string(result.Errors))
   420  				if err = sendError(conn, errors.New("Beep-bop, you're a robot!")); err != nil {
   421  					log.Warn("Failed to send captcha failure to client", "err", err)
   422  					return
   423  				}
   424  				continue
   425  			}
   426  		}
   427  //检索以太坊资金地址、请求用户和个人资料图片
   428  		var (
   429  			username string
   430  			avatar   string
   431  			address  common.Address
   432  		)
   433  		switch {
   434  case strings.HasPrefix(msg.URL, "https://gist.github.com/“):
   435  			if err = sendError(conn, errors.New("GitHub authentication discontinued at the official request of GitHub")); err != nil {
   436  				log.Warn("Failed to send GitHub deprecation to client", "err", err)
   437  				return
   438  			}
   439  			continue
   440  case strings.HasPrefix(msg.URL, "https://Twitter .com /():
   441  			username, avatar, address, err = authTwitter(msg.URL)
   442  case strings.HasPrefix(msg.URL, "https://加上google.com/“):
   443  			username, avatar, address, err = authGooglePlus(msg.URL)
   444  case strings.HasPrefix(msg.URL, "https://www.facebook.com/“):
   445  			username, avatar, address, err = authFacebook(msg.URL)
   446  		case *noauthFlag:
   447  			username, avatar, address, err = authNoAuth(msg.URL)
   448  		default:
   449  err = errors.New("Something funky happened, please open an issue at https://github.com/haxicode/go-ethereum/issues“)
   450  		}
   451  		if err != nil {
   452  			if err = sendError(conn, err); err != nil {
   453  				log.Warn("Failed to send prefix error to client", "err", err)
   454  				return
   455  			}
   456  			continue
   457  		}
   458  		log.Info("Faucet request valid", "url", msg.URL, "tier", msg.Tier, "user", username, "address", address)
   459  
   460  //确保用户最近没有申请资金
   461  		f.lock.Lock()
   462  		var (
   463  			fund    bool
   464  			timeout time.Time
   465  		)
   466  		if timeout = f.timeouts[username]; time.Now().After(timeout) {
   467  //用户最近没有资金,创建资金交易
   468  			amount := new(big.Int).Mul(big.NewInt(int64(*payoutFlag)), ether)
   469  			amount = new(big.Int).Mul(amount, new(big.Int).Exp(big.NewInt(5), big.NewInt(int64(msg.Tier)), nil))
   470  			amount = new(big.Int).Div(amount, new(big.Int).Exp(big.NewInt(2), big.NewInt(int64(msg.Tier)), nil))
   471  
   472  			tx := types.NewTransaction(types.Binary, f.nonce+uint64(len(f.reqs)), address, amount, 21000, f.price, nil)
   473  			signed, err := f.keystore.SignTx(f.account, tx, f.config.ChainID)
   474  			if err != nil {
   475  				f.lock.Unlock()
   476  				if err = sendError(conn, err); err != nil {
   477  					log.Warn("Failed to send transaction creation error to client", "err", err)
   478  					return
   479  				}
   480  				continue
   481  			}
   482  //
   483  			if err := f.client.SendTransaction(context.Background(), signed); err != nil {
   484  				f.lock.Unlock()
   485  				if err = sendError(conn, err); err != nil {
   486  					log.Warn("Failed to send transaction transmission error to client", "err", err)
   487  					return
   488  				}
   489  				continue
   490  			}
   491  			f.reqs = append(f.reqs, &request{
   492  				Avatar:  avatar,
   493  				Account: address,
   494  				Time:    time.Now(),
   495  				Tx:      signed,
   496  			})
   497  			f.timeouts[username] = time.Now().Add(time.Duration(*minutesFlag*int(math.Pow(3, float64(msg.Tier)))) * time.Minute)
   498  			fund = true
   499  		}
   500  		f.lock.Unlock()
   501  
   502  //如果融资过于频繁,则发送错误,否则将成功
   503  		if !fund {
   504  if err = sendError(conn, fmt.Errorf("%s left until next allowance", common.PrettyDuration(timeout.Sub(time.Now())))); err != nil { //诺林:天哪
   505  				log.Warn("Failed to send funding error to client", "err", err)
   506  				return
   507  			}
   508  			continue
   509  		}
   510  		if err = sendSuccess(conn, fmt.Sprintf("Funding request accepted for %s into %s", username, address.Hex())); err != nil {
   511  			log.Warn("Failed to send funding success to client", "err", err)
   512  			return
   513  		}
   514  		select {
   515  		case f.update <- struct{}{}:
   516  		default:
   517  		}
   518  	}
   519  }
   520  
   521  //循环一直在等待有趣的事件,并将它们推出到Connected
   522  //WebSoCukes。
   523  func (f *faucet) loop() {
   524  //等待链事件并将其推送到客户端
   525  	heads := make(chan *types.Header, 16)
   526  	sub, err := f.client.SubscribeNewHead(context.Background(), heads)
   527  	if err != nil {
   528  		log.Crit("Failed to subscribe to head events", "err", err)
   529  	}
   530  	defer sub.Unsubscribe()
   531  
   532  //启动goroutine以从后台的头通知更新状态
   533  	update := make(chan *types.Header)
   534  
   535  	go func() {
   536  		for head := range update {
   537  //新的链头到达,查询当前状态并流到客户端
   538  			var (
   539  				balance *big.Int
   540  				nonce   uint64
   541  				price   *big.Int
   542  				err     error
   543  			)
   544  			ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
   545  			balance, err = f.client.BalanceAt(ctx, f.account.Address, head.Number)
   546  			if err == nil {
   547  				nonce, err = f.client.NonceAt(ctx, f.account.Address, nil)
   548  				if err == nil {
   549  					price, err = f.client.SuggestGasPrice(ctx)
   550  				}
   551  			}
   552  			cancel()
   553  
   554  //如果查询数据失败,请尝试下一个块
   555  			if err != nil {
   556  				log.Warn("Failed to update faucet state", "block", head.Number, "hash", head.Hash(), "err", err)
   557  				continue
   558  			} else {
   559  				log.Info("Updated faucet state", "block", head.Number, "hash", head.Hash(), "balance", balance, "nonce", nonce, "price", price)
   560  			}
   561  //检索水龙头状态,本地更新并发送给客户
   562  			balance = new(big.Int).Div(balance, ether)
   563  
   564  			f.lock.Lock()
   565  			f.price, f.nonce = price, nonce
   566  			for len(f.reqs) > 0 && f.reqs[0].Tx.Nonce() < f.nonce {
   567  				f.reqs = f.reqs[1:]
   568  			}
   569  			f.lock.Unlock()
   570  
   571  			f.lock.RLock()
   572  			for _, conn := range f.conns {
   573  				if err := send(conn, map[string]interface{}{
   574  					"funds":    balance,
   575  					"funded":   f.nonce,
   576  					"peers":    f.stack.Server().PeerCount(),
   577  					"requests": f.reqs,
   578  				}, time.Second); err != nil {
   579  					log.Warn("Failed to send stats to client", "err", err)
   580  					conn.Close()
   581  					continue
   582  				}
   583  				if err := send(conn, head, time.Second); err != nil {
   584  					log.Warn("Failed to send header to client", "err", err)
   585  					conn.Close()
   586  				}
   587  			}
   588  			f.lock.RUnlock()
   589  		}
   590  	}()
   591  //等待各种事件并分配到适当的后台线程
   592  	for {
   593  		select {
   594  		case head := <-heads:
   595  //新的头已到达,如果没有运行则发送if以进行状态更新
   596  			select {
   597  			case update <- head:
   598  			default:
   599  			}
   600  
   601  		case <-f.update:
   602  //更新了挂起的请求,流式传输到客户端
   603  			f.lock.RLock()
   604  			for _, conn := range f.conns {
   605  				if err := send(conn, map[string]interface{}{"requests": f.reqs}, time.Second); err != nil {
   606  					log.Warn("Failed to send requests to client", "err", err)
   607  					conn.Close()
   608  				}
   609  			}
   610  			f.lock.RUnlock()
   611  		}
   612  	}
   613  }
   614  
   615  //发送数据包到WebSocket的远程端,但也
   616  //设置写入截止时间以防止永远等待在节点上。
   617  func send(conn *websocket.Conn, value interface{}, timeout time.Duration) error {
   618  	if timeout == 0 {
   619  		timeout = 60 * time.Second
   620  	}
   621  	conn.SetWriteDeadline(time.Now().Add(timeout))
   622  	return websocket.JSON.Send(conn, value)
   623  }
   624  
   625  //sendError将错误传输到WebSocket的远程端,同时设置
   626  //写截止时间为1秒,以防永远等待。
   627  func sendError(conn *websocket.Conn, err error) error {
   628  	return send(conn, map[string]string{"error": err.Error()}, time.Second)
   629  }
   630  
   631  //sendssuccess还将成功消息发送到websocket的远程端
   632  //将写入截止时间设置为1秒,以防止永远等待。
   633  func sendSuccess(conn *websocket.Conn, msg string) error {
   634  	return send(conn, map[string]string{"success": msg}, time.Second)
   635  }
   636  
   637  //AuthTwitter尝试使用Twitter帖子验证水龙头请求,返回
   638  //用户名、虚拟人物URL和以太坊地址将在成功时提供资金。
   639  func authTwitter(url string) (string, string, common.Address, error) {
   640  //确保用户指定了一个有意义的URL,没有花哨的胡说八道。
   641  	parts := strings.Split(url, "/")
   642  	if len(parts) < 4 || parts[len(parts)-2] != "status" {
   643  		return "", "", common.Address{}, errors.New("Invalid Twitter status URL")
   644  	}
   645  //
   646  //想做的是询问用户的读权限,所以只需加载公共文章和
   647  //从以太坊地址和配置文件URL中清除它。
   648  	res, err := http.Get(url)
   649  	if err != nil {
   650  		return "", "", common.Address{}, err
   651  	}
   652  	defer res.Body.Close()
   653  
   654  //从最终重定向中解析用户名,无中间垃圾邮件
   655  	parts = strings.Split(res.Request.URL.String(), "/")
   656  	if len(parts) < 4 || parts[len(parts)-2] != "status" {
   657  		return "", "", common.Address{}, errors.New("Invalid Twitter status URL")
   658  	}
   659  	username := parts[len(parts)-3]
   660  
   661  	body, err := ioutil.ReadAll(res.Body)
   662  	if err != nil {
   663  		return "", "", common.Address{}, err
   664  	}
   665  	address := common.HexToAddress(string(regexp.MustCompile("0x[0-9a-fA-F]{40}").Find(body)))
   666  	if address == (common.Address{}) {
   667  		return "", "", common.Address{}, errors.New("No Ethereum address found to fund")
   668  	}
   669  	var avatar string
   670  	if parts = regexp.MustCompile("src=\"([^\"]+twimg.com/profile_images[^\"]+)\"").FindStringSubmatch(string(body)); len(parts) == 2 {
   671  		avatar = parts[1]
   672  	}
   673  	return username + "@twitter", avatar, address, nil
   674  }
   675  
   676  //authgoogleplus尝试使用googleplus帖子验证水龙头请求,
   677  //成功后返回用户名、虚拟人物URL和以太坊地址进行投资。
   678  func authGooglePlus(url string) (string, string, common.Address, error) {
   679  //确保用户指定了一个有意义的URL,没有花哨的胡说八道。
   680  	parts := strings.Split(url, "/")
   681  	if len(parts) < 4 || parts[len(parts)-2] != "posts" {
   682  		return "", "", common.Address{}, errors.New("Invalid Google+ post URL")
   683  	}
   684  	username := parts[len(parts)-3]
   685  
   686  //谷歌的API对直接链接不是很友好。但是,我们没有
   687  //想做的是询问用户的读权限,所以只需加载公共文章和
   688  //从以太坊地址和配置文件URL中清除它。
   689  	res, err := http.Get(url)
   690  	if err != nil {
   691  		return "", "", common.Address{}, err
   692  	}
   693  	defer res.Body.Close()
   694  
   695  	body, err := ioutil.ReadAll(res.Body)
   696  	if err != nil {
   697  		return "", "", common.Address{}, err
   698  	}
   699  	address := common.HexToAddress(string(regexp.MustCompile("0x[0-9a-fA-F]{40}").Find(body)))
   700  	if address == (common.Address{}) {
   701  		return "", "", common.Address{}, errors.New("No Ethereum address found to fund")
   702  	}
   703  	var avatar string
   704  	if parts = regexp.MustCompile("src=\"([^\"]+googleusercontent.com[^\"]+photo.jpg)\"").FindStringSubmatch(string(body)); len(parts) == 2 {
   705  		avatar = parts[1]
   706  	}
   707  	return username + "@google+", avatar, address, nil
   708  }
   709  
   710  //AuthFacebook尝试使用Facebook帖子验证水龙头请求,
   711  //成功后返回用户名、虚拟人物URL和以太坊地址进行投资。
   712  func authFacebook(url string) (string, string, common.Address, error) {
   713  //确保用户指定了一个有意义的URL,没有花哨的胡说八道。
   714  	parts := strings.Split(url, "/")
   715  	if len(parts) < 4 || parts[len(parts)-2] != "posts" {
   716  		return "", "", common.Address{}, errors.New("Invalid Facebook post URL")
   717  	}
   718  	username := parts[len(parts)-3]
   719  
   720  //Facebook的图形API对直接链接不太友好。但是,我们没有
   721  //想做的是询问用户的读权限,所以只需加载公共文章和
   722  //从以太坊地址和配置文件URL中清除它。
   723  	res, err := http.Get(url)
   724  	if err != nil {
   725  		return "", "", common.Address{}, err
   726  	}
   727  	defer res.Body.Close()
   728  
   729  	body, err := ioutil.ReadAll(res.Body)
   730  	if err != nil {
   731  		return "", "", common.Address{}, err
   732  	}
   733  	address := common.HexToAddress(string(regexp.MustCompile("0x[0-9a-fA-F]{40}").Find(body)))
   734  	if address == (common.Address{}) {
   735  		return "", "", common.Address{}, errors.New("No Ethereum address found to fund")
   736  	}
   737  	var avatar string
   738  	if parts = regexp.MustCompile("src=\"([^\"]+fbcdn.net[^\"]+)\"").FindStringSubmatch(string(body)); len(parts) == 2 {
   739  		avatar = parts[1]
   740  	}
   741  	return username + "@facebook", avatar, address, nil
   742  }
   743  
   744  //AuthNoAuth试图将水龙头请求解释为一个普通的以太坊地址,
   745  //没有实际执行任何远程身份验证。这种模式很容易
   746  //拜占庭式攻击,所以只能用于真正的私人网络。
   747  func authNoAuth(url string) (string, string, common.Address, error) {
   748  	address := common.HexToAddress(regexp.MustCompile("0x[0-9a-fA-F]{40}").FindString(url))
   749  	if address == (common.Address{}) {
   750  		return "", "", common.Address{}, errors.New("No Ethereum address found to fund")
   751  	}
   752  	return address.Hex() + "@noauth", "", address, nil
   753  }
   754