plugeth/dashboard/peers.go

553 lines
20 KiB
Go
Raw Normal View History

2019-07-22 09:17:27 +00:00
// Copyright 2019 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 dashboard
import (
"container/list"
"strings"
"time"
"github.com/ethereum/go-ethereum/metrics"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/p2p"
)
const (
eventBufferLimit = 128 // Maximum number of buffered peer events.
knownPeerLimit = 100 // Maximum number of stored peers, which successfully made the handshake.
attemptLimit = 200 // Maximum number of stored peers, which failed to make the handshake.
// eventLimit is the maximum number of the dashboard's custom peer events,
// that are collected between two metering period and sent to the clients
// as one message.
// TODO (kurkomisi): Limit the number of events.
eventLimit = knownPeerLimit << 2
)
// peerContainer contains information about the node's peers. This data structure
// maintains the metered peer data based on the different behaviours of the peers.
//
// Every peer has an IP address, and the peers that manage to make the handshake
// (known peers) have node IDs too. There can appear more peers with the same IP,
// therefore the peer container data structure is a tree consisting of a map of
// maps, where the first key groups the peers by IP, while the second one groups
// them by the node ID. The known peers can be active if their connection is still
// open, or inactive otherwise. The peers failing before the handshake (unknown
// peers) only have IP addresses, so their connection attempts are stored as part
// of the value of the outer map.
//
// Another criteria is to limit the number of metered peers so that
// they don't fill the memory. The selection order is based on the
// peers activity: the peers that are inactive for the longest time
// are thrown first. For the selection a fifo list is used which is
// linked to the bottom of the peer tree in a way that every activity
// of the peer pushes the peer to the end of the list, so the inactive
// ones come to the front. When a peer has some activity, it is removed
// from and reinserted into the list. When the length of the list reaches
// the limit, the first element is removed from the list, as well as from
// the tree.
//
// The active peers have priority over the inactive ones, therefore
// they have their own list. The separation makes it sure that the
// inactive peers are always removed before the active ones.
//
// The peers that don't manage to make handshake are not inserted into the list,
// only their connection attempts are appended to the array belonging to their IP.
// In order to keep the fifo principle, a super array contains the order of the
// attempts, and when the overall count reaches the limit, the earliest attempt is
// removed from the beginning of its array.
//
// This data structure makes it possible to marshal the peer
// history simply by passing it to the JSON marshaler.
type peerContainer struct {
// Bundles is the outer map using the peer's IP address as key.
Bundles map[string]*peerBundle `json:"bundles,omitempty"`
activeCount int // Number of the still connected peers
// inactivePeers contains the peers with closed connection in chronological order.
inactivePeers *list.List
// attemptOrder is the super array containing the IP addresses, from which
// the peers attempted to connect then failed before/during the handshake.
// Its values are appended in chronological order, which means that the
// oldest attempt is at the beginning of the array. When the first element
// is removed, the first element of the related bundle's attempt array is
// removed too, ensuring that always the latest attempts are stored.
attemptOrder []string
// geodb is the geoip database used to retrieve the peers' geographical location.
geodb *geoDB
}
// newPeerContainer returns a new instance of the peer container.
func newPeerContainer(geodb *geoDB) *peerContainer {
return &peerContainer{
Bundles: make(map[string]*peerBundle),
inactivePeers: list.New(),
attemptOrder: make([]string, 0, attemptLimit),
geodb: geodb,
}
}
// bundle inserts a new peer bundle into the map, if the peer belonging
// to the given IP wasn't metered so far. In this case retrieves the location of
// the IP address from the database and creates a corresponding peer event.
// Returns the bundle belonging to the given IP and the events occurring during
// the initialization.
func (pc *peerContainer) bundle(ip string) (*peerBundle, []*peerEvent) {
var events []*peerEvent
if _, ok := pc.Bundles[ip]; !ok {
location := pc.geodb.location(ip)
events = append(events, &peerEvent{
IP: ip,
Location: location,
})
pc.Bundles[ip] = &peerBundle{
Location: location,
KnownPeers: make(map[string]*knownPeer),
}
}
return pc.Bundles[ip], events
}
// extendKnown handles the events of the successfully connected peers.
// Returns the events occurring during the extension.
func (pc *peerContainer) extendKnown(event *peerEvent) []*peerEvent {
bundle, events := pc.bundle(event.IP)
peer, peerEvents := bundle.knownPeer(event.IP, event.ID)
events = append(events, peerEvents...)
// Append the connect and the disconnect events to
// the corresponding arrays keeping the limit.
switch {
case event.Connected != nil:
peer.Connected = append(peer.Connected, event.Connected)
if first := len(peer.Connected) - sampleLimit; first > 0 {
peer.Connected = peer.Connected[first:]
}
peer.Active = true
events = append(events, &peerEvent{
Activity: Active,
IP: peer.ip,
ID: peer.id,
})
pc.activeCount++
if peer.listElement != nil {
_ = pc.inactivePeers.Remove(peer.listElement)
peer.listElement = nil
}
case event.Disconnected != nil:
peer.Disconnected = append(peer.Disconnected, event.Disconnected)
if first := len(peer.Disconnected) - sampleLimit; first > 0 {
peer.Disconnected = peer.Disconnected[first:]
}
peer.Active = false
events = append(events, &peerEvent{
Activity: Inactive,
IP: peer.ip,
ID: peer.id,
})
pc.activeCount--
if peer.listElement != nil {
// If the peer is already in the list, remove and reinsert it.
_ = pc.inactivePeers.Remove(peer.listElement)
}
// Insert the peer into the list.
peer.listElement = pc.inactivePeers.PushBack(peer)
}
for pc.inactivePeers.Len() > 0 && pc.activeCount+pc.inactivePeers.Len() > knownPeerLimit {
// While the count of the known peers is greater than the limit,
// remove the first element from the inactive peer list and from the map.
if removedPeer, ok := pc.inactivePeers.Remove(pc.inactivePeers.Front()).(*knownPeer); ok {
events = append(events, pc.removeKnown(removedPeer.ip, removedPeer.id)...)
} else {
log.Warn("Failed to parse the removed peer")
}
}
if pc.activeCount > knownPeerLimit {
log.Warn("Number of active peers is greater than the limit")
}
return events
}
// handleAttempt handles the events of the peers failing before/during the handshake.
// Returns the events occurring during the extension.
func (pc *peerContainer) handleAttempt(event *peerEvent) []*peerEvent {
bundle, events := pc.bundle(event.IP)
bundle.Attempts = append(bundle.Attempts, &peerAttempt{
Connected: *event.Connected,
Disconnected: *event.Disconnected,
})
pc.attemptOrder = append(pc.attemptOrder, event.IP)
for len(pc.attemptOrder) > attemptLimit {
// While the length of the connection attempt order array is greater
// than the limit, remove the first element from the involved peer's
// array and also from the super array.
events = append(events, pc.removeAttempt(pc.attemptOrder[0])...)
pc.attemptOrder = pc.attemptOrder[1:]
}
return events
}
// peerBundle contains the peers belonging to a given IP address.
type peerBundle struct {
// Location contains the geographical location based on the bundle's IP address.
Location *geoLocation `json:"location,omitempty"`
// KnownPeers is the inner map of the metered peer
// maintainer data structure using the node ID as key.
KnownPeers map[string]*knownPeer `json:"knownPeers,omitempty"`
// Attempts contains the failed connection attempts of the
// peers belonging to a given IP address in chronological order.
Attempts []*peerAttempt `json:"attempts,omitempty"`
}
// removeKnown removes the known peer belonging to the
// given IP address and node ID from the peer tree.
func (pc *peerContainer) removeKnown(ip, id string) (events []*peerEvent) {
// TODO (kurkomisi): Remove peers that don't have traffic samples anymore.
if bundle, ok := pc.Bundles[ip]; ok {
if _, ok := bundle.KnownPeers[id]; ok {
events = append(events, &peerEvent{
Remove: RemoveKnown,
IP: ip,
ID: id,
})
delete(bundle.KnownPeers, id)
} else {
log.Warn("No peer to remove", "ip", ip, "id", id)
}
if len(bundle.KnownPeers) < 1 && len(bundle.Attempts) < 1 {
events = append(events, &peerEvent{
Remove: RemoveBundle,
IP: ip,
})
delete(pc.Bundles, ip)
}
} else {
log.Warn("No bundle to remove", "ip", ip)
}
return events
}
// removeAttempt removes the peer attempt belonging to the
// given IP address and node ID from the peer tree.
func (pc *peerContainer) removeAttempt(ip string) (events []*peerEvent) {
if bundle, ok := pc.Bundles[ip]; ok {
if len(bundle.Attempts) > 0 {
events = append(events, &peerEvent{
Remove: RemoveAttempt,
IP: ip,
})
bundle.Attempts = bundle.Attempts[1:]
}
if len(bundle.Attempts) < 1 && len(bundle.KnownPeers) < 1 {
events = append(events, &peerEvent{
Remove: RemoveBundle,
IP: ip,
})
delete(pc.Bundles, ip)
}
}
return events
}
// knownPeer inserts a new peer into the map, if the peer belonging
// to the given IP address and node ID wasn't metered so far. Returns the peer
// belonging to the given IP and ID as well as the events occurring during the
// initialization.
func (bundle *peerBundle) knownPeer(ip, id string) (*knownPeer, []*peerEvent) {
var events []*peerEvent
if _, ok := bundle.KnownPeers[id]; !ok {
now := time.Now()
ingress := emptyChartEntries(now, sampleLimit)
egress := emptyChartEntries(now, sampleLimit)
events = append(events, &peerEvent{
IP: ip,
ID: id,
Ingress: append([]*ChartEntry{}, ingress...),
Egress: append([]*ChartEntry{}, egress...),
})
bundle.KnownPeers[id] = &knownPeer{
ip: ip,
id: id,
Ingress: ingress,
Egress: egress,
}
}
return bundle.KnownPeers[id], events
}
// knownPeer contains the metered data of a particular peer.
type knownPeer struct {
// Connected contains the timestamps of the peer's connection events.
Connected []*time.Time `json:"connected,omitempty"`
// Disconnected contains the timestamps of the peer's disconnection events.
Disconnected []*time.Time `json:"disconnected,omitempty"`
// Ingress and Egress contain the peer's traffic samples, which are collected
// periodically from the metrics registry.
//
// A peer can connect multiple times, and we want to visualize the time
// passed between two connections, so after the first connection a 0 value
// is appended to the traffic arrays even if the peer is inactive until the
// peer is removed.
Ingress ChartEntries `json:"ingress,omitempty"`
Egress ChartEntries `json:"egress,omitempty"`
Active bool `json:"active"` // Denotes if the peer is still connected.
listElement *list.Element // Pointer to the peer element in the list.
ip, id string // The IP and the ID by which the peer can be accessed in the tree.
prevIngress float64
prevEgress float64
}
// peerAttempt contains a failed peer connection attempt's attributes.
type peerAttempt struct {
// Connected contains the timestamp of the connection attempt's moment.
Connected time.Time `json:"connected"`
// Disconnected contains the timestamp of the
// moment when the connection attempt failed.
Disconnected time.Time `json:"disconnected"`
}
type RemovedPeerType string
type ActivityType string
const (
RemoveKnown RemovedPeerType = "known"
RemoveAttempt RemovedPeerType = "attempt"
RemoveBundle RemovedPeerType = "bundle"
Active ActivityType = "active"
Inactive ActivityType = "inactive"
)
// peerEvent contains the attributes of a peer event.
type peerEvent struct {
IP string `json:"ip,omitempty"` // IP address of the peer.
ID string `json:"id,omitempty"` // Node ID of the peer.
Remove RemovedPeerType `json:"remove,omitempty"` // Type of the peer that is to be removed.
Location *geoLocation `json:"location,omitempty"` // Geographical location of the peer.
Connected *time.Time `json:"connected,omitempty"` // Timestamp of the connection moment.
Disconnected *time.Time `json:"disconnected,omitempty"` // Timestamp of the disonnection moment.
Ingress ChartEntries `json:"ingress,omitempty"` // Ingress samples.
Egress ChartEntries `json:"egress,omitempty"` // Egress samples.
Activity ActivityType `json:"activity,omitempty"` // Connection status change.
}
// trafficMap is a container for the periodically collected peer traffic.
type trafficMap map[string]map[string]float64
// insert inserts a new value to the traffic map. Overwrites
// the value at the given ip and id if that already exists.
func (m *trafficMap) insert(ip, id string, val float64) {
if _, ok := (*m)[ip]; !ok {
(*m)[ip] = make(map[string]float64)
}
(*m)[ip][id] = val
}
// collectPeerData gathers data about the peers and sends it to the clients.
func (db *Dashboard) collectPeerData() {
defer db.wg.Done()
// Open the geodb database for IP to geographical information conversions.
var err error
db.geodb, err = openGeoDB()
if err != nil {
log.Warn("Failed to open geodb", "err", err)
return
}
defer db.geodb.close()
peerCh := make(chan p2p.MeteredPeerEvent, eventBufferLimit) // Peer event channel.
subPeer := p2p.SubscribeMeteredPeerEvent(peerCh) // Subscribe to peer events.
defer subPeer.Unsubscribe() // Unsubscribe at the end.
ticker := time.NewTicker(db.config.Refresh)
defer ticker.Stop()
type registryFunc func(name string, i interface{})
type collectorFunc func(traffic *trafficMap) registryFunc
// trafficCollector generates a function that can be passed to
// the prefixed peer registry in order to collect the metered
// traffic data from each peer meter.
trafficCollector := func(prefix string) collectorFunc {
// This part makes is possible to collect the
// traffic data into a map from outside.
return func(traffic *trafficMap) registryFunc {
// The function which can be passed to the registry.
return func(name string, i interface{}) {
if m, ok := i.(metrics.Meter); ok {
// The name of the meter has the format: <common traffic prefix><IP>/<ID>
if k := strings.Split(strings.TrimPrefix(name, prefix), "/"); len(k) == 2 {
traffic.insert(k[0], k[1], float64(m.Count()))
} else {
log.Warn("Invalid meter name", "name", name, "prefix", prefix)
}
} else {
log.Warn("Invalid meter type", "name", name)
}
}
}
}
collectIngress := trafficCollector(p2p.MetricsInboundTraffic + "/")
collectEgress := trafficCollector(p2p.MetricsOutboundTraffic + "/")
peers := newPeerContainer(db.geodb)
db.peerLock.Lock()
db.history.Network = &NetworkMessage{
Peers: peers,
}
db.peerLock.Unlock()
// newPeerEvents contains peer events, which trigger operations that
// will be executed on the peer tree after a metering period.
newPeerEvents := make([]*peerEvent, 0, eventLimit)
ingress, egress := new(trafficMap), new(trafficMap)
*ingress, *egress = make(trafficMap), make(trafficMap)
for {
select {
case event := <-peerCh:
now := time.Now()
switch event.Type {
case p2p.PeerConnected:
connected := now.Add(-event.Elapsed)
newPeerEvents = append(newPeerEvents, &peerEvent{
IP: event.IP.String(),
ID: event.ID.String(),
Connected: &connected,
})
case p2p.PeerDisconnected:
ip, id := event.IP.String(), event.ID.String()
newPeerEvents = append(newPeerEvents, &peerEvent{
IP: ip,
ID: id,
Disconnected: &now,
})
// The disconnect event comes with the last metered traffic count,
// because after the disconnection the peer's meter is removed
// from the registry. It can happen, that between two metering
// period the same peer disconnects multiple times, and appending
// all the samples to the traffic arrays would shift the metering,
// so only the last metering is stored, overwriting the previous one.
ingress.insert(ip, id, float64(event.Ingress))
egress.insert(ip, id, float64(event.Egress))
case p2p.PeerHandshakeFailed:
connected := now.Add(-event.Elapsed)
newPeerEvents = append(newPeerEvents, &peerEvent{
IP: event.IP.String(),
Connected: &connected,
Disconnected: &now,
})
default:
log.Error("Unknown metered peer event type", "type", event.Type)
}
case <-ticker.C:
// Collect the traffic samples from the registry.
p2p.PeerIngressRegistry.Each(collectIngress(ingress))
p2p.PeerEgressRegistry.Each(collectEgress(egress))
// Protect 'peers', because it is part of the history.
db.peerLock.Lock()
var diff []*peerEvent
for i := 0; i < len(newPeerEvents); i++ {
if newPeerEvents[i].IP == "" {
log.Warn("Peer event without IP", "event", *newPeerEvents[i])
continue
}
diff = append(diff, newPeerEvents[i])
// There are two main branches of peer events coming from the event
// feed, one belongs to the known peers, one to the unknown peers.
// If the event has node ID, it belongs to a known peer, otherwise
// to an unknown one, which is considered as connection attempt.
//
// The extension can produce additional peer events, such
// as remove, location and initial samples events.
if newPeerEvents[i].ID == "" {
diff = append(diff, peers.handleAttempt(newPeerEvents[i])...)
continue
}
diff = append(diff, peers.extendKnown(newPeerEvents[i])...)
}
// Update the peer tree using the traffic maps.
for ip, bundle := range peers.Bundles {
for id, peer := range bundle.KnownPeers {
// Value is 0 if the traffic map doesn't have the
// entry corresponding to the given IP and ID.
curIngress, curEgress := (*ingress)[ip][id], (*egress)[ip][id]
deltaIngress, deltaEgress := curIngress, curEgress
if deltaIngress >= peer.prevIngress {
deltaIngress -= peer.prevIngress
}
if deltaEgress >= peer.prevEgress {
deltaEgress -= peer.prevEgress
}
peer.prevIngress, peer.prevEgress = curIngress, curEgress
i := &ChartEntry{
Value: deltaIngress,
}
e := &ChartEntry{
Value: deltaEgress,
}
peer.Ingress = append(peer.Ingress, i)
peer.Egress = append(peer.Egress, e)
if first := len(peer.Ingress) - sampleLimit; first > 0 {
peer.Ingress = peer.Ingress[first:]
}
if first := len(peer.Egress) - sampleLimit; first > 0 {
peer.Egress = peer.Egress[first:]
}
// Creating the traffic sample events.
diff = append(diff, &peerEvent{
IP: ip,
ID: id,
Ingress: ChartEntries{i},
Egress: ChartEntries{e},
})
}
}
db.peerLock.Unlock()
if len(diff) > 0 {
db.sendToAll(&Message{Network: &NetworkMessage{
Diff: diff,
}})
}
// Clear the traffic maps, and the event array,
// prepare them for the next metering.
*ingress, *egress = make(trafficMap), make(trafficMap)
newPeerEvents = newPeerEvents[:0]
case err := <-subPeer.Err():
log.Warn("Peer subscription error", "err", err)
return
case errc := <-db.quit:
errc <- nil
return
}
}
}