// Copyright 2016 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
// Package ethstats implements the network stats reporting service.
package ethstats
import (
"context"
"encoding/json"
"errors"
"fmt"
"math/big"
"net"
"regexp"
"runtime"
"strconv"
"strings"
"time"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/common/mclock"
"github.com/ethereum/go-ethereum/consensus"
"github.com/ethereum/go-ethereum/core"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/eth"
"github.com/ethereum/go-ethereum/event"
"github.com/ethereum/go-ethereum/les"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/p2p"
"github.com/ethereum/go-ethereum/rpc"
"golang.org/x/net/websocket"
)
const (
// historyUpdateRange is the number of blocks a node should report upon login or
// history request.
historyUpdateRange = 50
// txChanSize is the size of channel listening to TxPreEvent.
// The number is referenced from the size of tx pool.
txChanSize = 4096
// chainHeadChanSize is the size of channel listening to ChainHeadEvent.
chainHeadChanSize = 10
)
type txPool interface {
// SubscribeTxPreEvent should return an event subscription of
// TxPreEvent and send events to the given channel.
SubscribeTxPreEvent(chan<- core.TxPreEvent) event.Subscription
}
type blockChain interface {
SubscribeChainHeadEvent(ch chan<- core.ChainHeadEvent) event.Subscription
}
// Service implements an Ethereum netstats reporting daemon that pushes local
// chain statistics up to a monitoring server.
type Service struct {
server *p2p.Server // Peer-to-peer server to retrieve networking infos
eth *eth.Ethereum // Full Ethereum service if monitoring a full node
les *les.LightEthereum // Light Ethereum service if monitoring a light node
engine consensus.Engine // Consensus engine to retrieve variadic block fields
node string // Name of the node to display on the monitoring page
pass string // Password to authorize access to the monitoring page
host string // Remote address of the monitoring service
pongCh chan struct{} // Pong notifications are fed into this channel
histCh chan []uint64 // History request block numbers are fed into this channel
}
// New returns a monitoring service ready for stats reporting.
func New(url string, ethServ *eth.Ethereum, lesServ *les.LightEthereum) (*Service, error) {
// Parse the netstats connection url
re := regexp.MustCompile("([^:@]*)(:([^@]*))?@(.+)")
parts := re.FindStringSubmatch(url)
if len(parts) != 5 {
return nil, fmt.Errorf("invalid netstats url: \"%s\", should be nodename:secret@host:port", url)
}
// Assemble and return the stats service
var engine consensus.Engine
if ethServ != nil {
engine = ethServ.Engine()
} else {
engine = lesServ.Engine()
}
return &Service{
eth: ethServ,
les: lesServ,
engine: engine,
node: parts[1],
pass: parts[3],
host: parts[4],
pongCh: make(chan struct{}),
histCh: make(chan []uint64, 1),
}, nil
}
// Protocols implements node.Service, returning the P2P network protocols used
// by the stats service (nil as it doesn't use the devp2p overlay network).
func (s *Service) Protocols() []p2p.Protocol { return nil }
// APIs implements node.Service, returning the RPC API endpoints provided by the
// stats service (nil as it doesn't provide any user callable APIs).
func (s *Service) APIs() []rpc.API { return nil }
// Start implements node.Service, starting up the monitoring and reporting daemon.
func (s *Service) Start(server *p2p.Server) error {
s.server = server
go s.loop()
log.Info("Stats daemon started")
return nil
}
// Stop implements node.Service, terminating the monitoring and reporting daemon.
func (s *Service) Stop() error {
log.Info("Stats daemon stopped")
return nil
}
// loop keeps trying to connect to the netstats server, reporting chain events
// until termination.
func (s *Service) loop() {
// Subscribe to chain events to execute updates on
var blockchain blockChain
var txpool txPool
if s.eth != nil {
blockchain = s.eth.BlockChain()
txpool = s.eth.TxPool()
} else {
blockchain = s.les.BlockChain()
txpool = s.les.TxPool()
}
chainHeadCh := make(chan core.ChainHeadEvent, chainHeadChanSize)
headSub := blockchain.SubscribeChainHeadEvent(chainHeadCh)
defer headSub.Unsubscribe()
txEventCh := make(chan core.TxPreEvent, txChanSize)
txSub := txpool.SubscribeTxPreEvent(txEventCh)
defer txSub.Unsubscribe()
// Start a goroutine that exhausts the subsciptions to avoid events piling up
var (
quitCh = make(chan struct{})
headCh = make(chan *types.Block, 1)
txCh = make(chan struct{}, 1)
)
go func() {
var lastTx mclock.AbsTime
HandleLoop:
for {
select {
// Notify of chain head events, but drop if too frequent
case head := <-chainHeadCh:
select {
case headCh <- head.Block:
default:
}
// Notify of new transaction events, but drop if too frequent
case <-txEventCh:
if time.Duration(mclock.Now()-lastTx) < time.Second {
continue
}
lastTx = mclock.Now()
select {
case txCh <- struct{}{}:
default:
}
// node stopped
case <-txSub.Err():
break HandleLoop
case <-headSub.Err():
break HandleLoop
}
}
close(quitCh)
}()
// Loop reporting until termination
for {
// Resolve the URL, defaulting to TLS, but falling back to none too
path := fmt.Sprintf("%s/api", s.host)
urls := []string{path}
if !strings.Contains(path, "://") { // url.Parse and url.IsAbs is unsuitable (https://github.com/golang/go/issues/19779)
urls = []string{"wss://" + path, "ws://" + path}
}
// Establish a websocket connection to the server on any supported URL
var (
conf *websocket.Config
conn *websocket.Conn
err error
)
for _, url := range urls {
if conf, err = websocket.NewConfig(url, "http://localhost/"); err != nil {
continue
}
conf.Dialer = &net.Dialer{Timeout: 5 * time.Second}
if conn, err = websocket.DialConfig(conf); err == nil {
break
}
}
if err != nil {
log.Warn("Stats server unreachable", "err", err)
time.Sleep(10 * time.Second)
continue
}
// Authenticate the client with the server
if err = s.login(conn); err != nil {
log.Warn("Stats login failed", "err", err)
conn.Close()
time.Sleep(10 * time.Second)
continue
}
go s.readLoop(conn)
// Send the initial stats so our node looks decent from the get go
if err = s.report(conn); err != nil {
log.Warn("Initial stats report failed", "err", err)
conn.Close()
continue
}
// Keep sending status updates until the connection breaks
fullReport := time.NewTicker(15 * time.Second)
for err == nil {
select {
case <-quitCh:
conn.Close()
return
case <-fullReport.C:
if err = s.report(conn); err != nil {
log.Warn("Full stats report failed", "err", err)
}
case list := <-s.histCh:
if err = s.reportHistory(conn, list); err != nil {
log.Warn("Requested history report failed", "err", err)
}
case head := <-headCh:
if err = s.reportBlock(conn, head); err != nil {
log.Warn("Block stats report failed", "err", err)
}
if err = s.reportPending(conn); err != nil {
log.Warn("Post-block transaction stats report failed", "err", err)
}
case <-txCh:
if err = s.reportPending(conn); err != nil {
log.Warn("Transaction stats report failed", "err", err)
}
}
}
// Make sure the connection is closed
conn.Close()
}
}
// readLoop loops as long as the connection is alive and retrieves data packets
// from the network socket. If any of them match an active request, it forwards
// it, if they themselves are requests it initiates a reply, and lastly it drops
// unknown packets.
func (s *Service) readLoop(conn *websocket.Conn) {
// If the read loop exists, close the connection
defer conn.Close()
for {
// Retrieve the next generic network packet and bail out on error
var msg map[string][]interface{}
if err := websocket.JSON.Receive(conn, &msg); err != nil {
log.Warn("Failed to decode stats server message", "err", err)
return
}
log.Trace("Received message from stats server", "msg", msg)
if len(msg["emit"]) == 0 {
log.Warn("Stats server sent non-broadcast", "msg", msg)
return
}
command, ok := msg["emit"][0].(string)
if !ok {
log.Warn("Invalid stats server message type", "type", msg["emit"][0])
return
}
// If the message is a ping reply, deliver (someone must be listening!)
if len(msg["emit"]) == 2 && command == "node-pong" {
select {
case s.pongCh <- struct{}{}:
// Pong delivered, continue listening
continue
default:
// Ping routine dead, abort
log.Warn("Stats server pinger seems to have died")
return
}
}
// If the message is a history request, forward to the event processor
if len(msg["emit"]) == 2 && command == "history" {
// Make sure the request is valid and doesn't crash us
request, ok := msg["emit"][1].(map[string]interface{})
if !ok {
log.Warn("Invalid stats history request", "msg", msg["emit"][1])
s.histCh <- nil
continue // Ethstats sometime sends invalid history requests, ignore those
}
list, ok := request["list"].([]interface{})
if !ok {
log.Warn("Invalid stats history block list", "list", request["list"])
return
}
// Convert the block number list to an integer list
numbers := make([]uint64, len(list))
for i, num := range list {
n, ok := num.(float64)
if !ok {
log.Warn("Invalid stats history block number", "number", num)
return
}
numbers[i] = uint64(n)
}
select {
case s.histCh <- numbers:
continue
default:
}
}
// Report anything else and continue
log.Info("Unknown stats message", "msg", msg)
}
}
// nodeInfo is the collection of metainformation about a node that is displayed
// on the monitoring page.
type nodeInfo struct {
Name string `json:"name"`
Node string `json:"node"`
Port int `json:"port"`
Network string `json:"net"`
Protocol string `json:"protocol"`
API string `json:"api"`
Os string `json:"os"`
OsVer string `json:"os_v"`
Client string `json:"client"`
History bool `json:"canUpdateHistory"`
}
// authMsg is the authentication infos needed to login to a monitoring server.
type authMsg struct {
Id string `json:"id"`
Info nodeInfo `json:"info"`
Secret string `json:"secret"`
}
// login tries to authorize the client at the remote server.
func (s *Service) login(conn *websocket.Conn) error {
// Construct and send the login authentication
infos := s.server.NodeInfo()
var network, protocol string
if info := infos.Protocols["eth"]; info != nil {
network = fmt.Sprintf("%d", info.(*eth.EthNodeInfo).Network)
protocol = fmt.Sprintf("eth/%d", eth.ProtocolVersions[0])
} else {
network = fmt.Sprintf("%d", infos.Protocols["les"].(*eth.EthNodeInfo).Network)
protocol = fmt.Sprintf("les/%d", les.ClientProtocolVersions[0])
}
auth := &authMsg{
Id: s.node,
Info: nodeInfo{
Name: s.node,
Node: infos.Name,
Port: infos.Ports.Listener,
Network: network,
Protocol: protocol,
API: "No",
Os: runtime.GOOS,
OsVer: runtime.GOARCH,
Client: "0.1.1",
History: true,
},
Secret: s.pass,
}
login := map[string][]interface{}{
"emit": {"hello", auth},
}
if err := websocket.JSON.Send(conn, login); err != nil {
return err
}
// Retrieve the remote ack or connection termination
var ack map[string][]string
if err := websocket.JSON.Receive(conn, &ack); err != nil || len(ack["emit"]) != 1 || ack["emit"][0] != "ready" {
return errors.New("unauthorized")
}
return nil
}
// report collects all possible data to report and send it to the stats server.
// This should only be used on reconnects or rarely to avoid overloading the
// server. Use the individual methods for reporting subscribed events.
func (s *Service) report(conn *websocket.Conn) error {
if err := s.reportLatency(conn); err != nil {
return err
}
if err := s.reportBlock(conn, nil); err != nil {
return err
}
if err := s.reportPending(conn); err != nil {
return err
}
if err := s.reportStats(conn); err != nil {
return err
}
return nil
}
// reportLatency sends a ping request to the server, measures the RTT time and
// finally sends a latency update.
func (s *Service) reportLatency(conn *websocket.Conn) error {
// Send the current time to the ethstats server
start := time.Now()
ping := map[string][]interface{}{
"emit": {"node-ping", map[string]string{
"id": s.node,
"clientTime": start.String(),
}},
}
if err := websocket.JSON.Send(conn, ping); err != nil {
return err
}
// Wait for the pong request to arrive back
select {
case <-s.pongCh:
// Pong delivered, report the latency
case <-time.After(5 * time.Second):
// Ping timeout, abort
return errors.New("ping timed out")
}
latency := strconv.Itoa(int((time.Since(start) / time.Duration(2)).Nanoseconds() / 1000000))
// Send back the measured latency
log.Trace("Sending measured latency to ethstats", "latency", latency)
stats := map[string][]interface{}{
"emit": {"latency", map[string]string{
"id": s.node,
"latency": latency,
}},
}
return websocket.JSON.Send(conn, stats)
}
// blockStats is the information to report about individual blocks.
type blockStats struct {
Number *big.Int `json:"number"`
Hash common.Hash `json:"hash"`
ParentHash common.Hash `json:"parentHash"`
Timestamp *big.Int `json:"timestamp"`
Miner common.Address `json:"miner"`
GasUsed *big.Int `json:"gasUsed"`
GasLimit *big.Int `json:"gasLimit"`
Diff string `json:"difficulty"`
TotalDiff string `json:"totalDifficulty"`
Txs []txStats `json:"transactions"`
TxHash common.Hash `json:"transactionsRoot"`
Root common.Hash `json:"stateRoot"`
Uncles uncleStats `json:"uncles"`
}
// txStats is the information to report about individual transactions.
type txStats struct {
Hash common.Hash `json:"hash"`
}
// uncleStats is a custom wrapper around an uncle array to force serializing
// empty arrays instead of returning null for them.
type uncleStats []*types.Header
func (s uncleStats) MarshalJSON() ([]byte, error) {
if uncles := ([]*types.Header)(s); len(uncles) > 0 {
return json.Marshal(uncles)
}
return []byte("[]"), nil
}
// reportBlock retrieves the current chain head and repors it to the stats server.
func (s *Service) reportBlock(conn *websocket.Conn, block *types.Block) error {
// Gather the block details from the header or block chain
details := s.assembleBlockStats(block)
// Assemble the block report and send it to the server
log.Trace("Sending new block to ethstats", "number", details.Number, "hash", details.Hash)
stats := map[string]interface{}{
"id": s.node,
"block": details,
}
report := map[string][]interface{}{
"emit": {"block", stats},
}
return websocket.JSON.Send(conn, report)
}
// assembleBlockStats retrieves any required metadata to report a single block
// and assembles the block stats. If block is nil, the current head is processed.
func (s *Service) assembleBlockStats(block *types.Block) *blockStats {
// Gather the block infos from the local blockchain
var (
header *types.Header
td *big.Int
txs []txStats
uncles []*types.Header
)
if s.eth != nil {
// Full nodes have all needed information available
if block == nil {
block = s.eth.BlockChain().CurrentBlock()
}
header = block.Header()
td = s.eth.BlockChain().GetTd(header.Hash(), header.Number.Uint64())
txs = make([]txStats, len(block.Transactions()))
for i, tx := range block.Transactions() {
txs[i].Hash = tx.Hash()
}
uncles = block.Uncles()
} else {
// Light nodes would need on-demand lookups for transactions/uncles, skip
if block != nil {
header = block.Header()
} else {
header = s.les.BlockChain().CurrentHeader()
}
td = s.les.BlockChain().GetTd(header.Hash(), header.Number.Uint64())
txs = []txStats{}
}
// Assemble and return the block stats
author, _ := s.engine.Author(header)
return &blockStats{
Number: header.Number,
Hash: header.Hash(),
ParentHash: header.ParentHash,
Timestamp: header.Time,
Miner: author,
GasUsed: new(big.Int).Set(header.GasUsed),
GasLimit: new(big.Int).Set(header.GasLimit),
Diff: header.Difficulty.String(),
TotalDiff: td.String(),
Txs: txs,
TxHash: header.TxHash,
Root: header.Root,
Uncles: uncles,
}
}
// reportHistory retrieves the most recent batch of blocks and reports it to the
// stats server.
func (s *Service) reportHistory(conn *websocket.Conn, list []uint64) error {
// Figure out the indexes that need reporting
indexes := make([]uint64, 0, historyUpdateRange)
if len(list) > 0 {
// Specific indexes requested, send them back in particular
indexes = append(indexes, list...)
} else {
// No indexes requested, send back the top ones
var head int64
if s.eth != nil {
head = s.eth.BlockChain().CurrentHeader().Number.Int64()
} else {
head = s.les.BlockChain().CurrentHeader().Number.Int64()
}
start := head - historyUpdateRange + 1
if start < 0 {
start = 0
}
for i := uint64(start); i <= uint64(head); i++ {
indexes = append(indexes, i)
}
}
// Gather the batch of blocks to report
history := make([]*blockStats, len(indexes))
for i, number := range indexes {
// Retrieve the next block if it's known to us
var block *types.Block
if s.eth != nil {
block = s.eth.BlockChain().GetBlockByNumber(number)
} else {
if header := s.les.BlockChain().GetHeaderByNumber(number); header != nil {
block = types.NewBlockWithHeader(header)
}
}
// If we do have the block, add to the history and continue
if block != nil {
history[len(history)-1-i] = s.assembleBlockStats(block)
continue
}
// Ran out of blocks, cut the report short and send
history = history[len(history)-i:]
}
// Assemble the history report and send it to the server
if len(history) > 0 {
log.Trace("Sending historical blocks to ethstats", "first", history[0].Number, "last", history[len(history)-1].Number)
} else {
log.Trace("No history to send to stats server")
}
stats := map[string]interface{}{
"id": s.node,
"history": history,
}
report := map[string][]interface{}{
"emit": {"history", stats},
}
return websocket.JSON.Send(conn, report)
}
// pendStats is the information to report about pending transactions.
type pendStats struct {
Pending int `json:"pending"`
}
// reportPending retrieves the current number of pending transactions and reports
// it to the stats server.
func (s *Service) reportPending(conn *websocket.Conn) error {
// Retrieve the pending count from the local blockchain
var pending int
if s.eth != nil {
pending, _ = s.eth.TxPool().Stats()
} else {
pending = s.les.TxPool().Stats()
}
// Assemble the transaction stats and send it to the server
log.Trace("Sending pending transactions to ethstats", "count", pending)
stats := map[string]interface{}{
"id": s.node,
"stats": &pendStats{
Pending: pending,
},
}
report := map[string][]interface{}{
"emit": {"pending", stats},
}
return websocket.JSON.Send(conn, report)
}
// nodeStats is the information to report about the local node.
type nodeStats struct {
Active bool `json:"active"`
Syncing bool `json:"syncing"`
Mining bool `json:"mining"`
Hashrate int `json:"hashrate"`
Peers int `json:"peers"`
GasPrice int `json:"gasPrice"`
Uptime int `json:"uptime"`
}
// reportPending retrieves various stats about the node at the networking and
// mining layer and reports it to the stats server.
func (s *Service) reportStats(conn *websocket.Conn) error {
// Gather the syncing and mining infos from the local miner instance
var (
mining bool
hashrate int
syncing bool
gasprice int
)
if s.eth != nil {
mining = s.eth.Miner().Mining()
hashrate = int(s.eth.Miner().HashRate())
sync := s.eth.Downloader().Progress()
syncing = s.eth.BlockChain().CurrentHeader().Number.Uint64() >= sync.HighestBlock
price, _ := s.eth.ApiBackend.SuggestPrice(context.Background())
gasprice = int(price.Uint64())
} else {
sync := s.les.Downloader().Progress()
syncing = s.les.BlockChain().CurrentHeader().Number.Uint64() >= sync.HighestBlock
}
// Assemble the node stats and send it to the server
log.Trace("Sending node details to ethstats")
stats := map[string]interface{}{
"id": s.node,
"stats": &nodeStats{
Active: true,
Mining: mining,
Hashrate: hashrate,
Peers: s.server.PeerCount(),
GasPrice: gasprice,
Syncing: syncing,
Uptime: 100,
},
}
report := map[string][]interface{}{
"emit": {"stats", stats},
}
return websocket.JSON.Send(conn, report)
}
