go-pulse/ethstats/ethstats.go
Felix Lange 04e175b8ec rpc: implement websockets with github.com/gorilla/websocket (#19866)
* rpc: implement websockets with github.com/gorilla/websocket

This change makes package rpc use the github.com/gorilla/websocket
package for WebSockets instead of golang.org/x/net/websocket. The new
library is more robust and supports all WebSocket features including
continuation frames.

There are new tests for two issues with the previously-used library:

  - TestWebsocketClientPing checks handling of Ping frames.
  - TestWebsocketLargeCall checks whether the request size limit is
    applied correctly.

* rpc: raise HTTP/WebSocket request size limit to 5MB

* rpc: remove default origin for client connections

The client used to put the local hostname into the Origin header because
the server wanted an origin to accept the connection, but that's silly:
Origin is for browsers/websites. The nobody would whitelist a particular
hostname.

Now that the server doesn't need Origin anymore, don't bother setting
one for clients. Users who need an origin can use DialWebsocket to
create a client with arbitrary origin if needed.

* vendor: put golang.org/x/net/websocket back

* rpc: don't set Origin header for empty (default) origin

* rpc: add HTTP status code to handshake error

This makes it easier to debug failing connections.

* ethstats: use github.com/gorilla/websocket

* rpc: fix lint
2019-07-22 13:22:39 +03:00

718 lines
21 KiB
Go

// 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/http"
"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"
"github.com/gorilla/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 NewTxsEvent.
// 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 {
// SubscribeNewTxsEvent should return an event subscription of
// NewTxsEvent and send events to the given channel.
SubscribeNewTxsEvent(chan<- core.NewTxsEvent) 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.NewTxsEvent, txChanSize)
txSub := txpool.SubscribeNewTxsEvent(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}
// url.Parse and url.IsAbs is unsuitable (https://github.com/golang/go/issues/19779)
if !strings.Contains(path, "://") {
urls = []string{"wss://" + path, "ws://" + path}
}
// Establish a websocket connection to the server on any supported URL
var (
conn *websocket.Conn
err error
)
dialer := websocket.Dialer{HandshakeTimeout: 5 * time.Second}
header := make(http.Header)
header.Set("origin", "http://localhost")
for _, url := range urls {
conn, _, err = dialer.Dial(url, header)
if 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 := conn.ReadJSON(&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.NodeInfo).Network)
protocol = fmt.Sprintf("eth/%d", eth.ProtocolVersions[0])
} else {
network = fmt.Sprintf("%d", infos.Protocols["les"].(*les.NodeInfo).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 := conn.WriteJSON(login); err != nil {
return err
}
// Retrieve the remote ack or connection termination
var ack map[string][]string
if err := conn.ReadJSON(&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 := conn.WriteJSON(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 conn.WriteJSON(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 uint64 `json:"gasUsed"`
GasLimit uint64 `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 reports 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 conn.WriteJSON(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: new(big.Int).SetUint64(header.Time),
Miner: author,
GasUsed: header.GasUsed,
GasLimit: 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:]
break
}
// 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 conn.WriteJSON(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 conn.WriteJSON(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 conn.WriteJSON(report)
}