// Copyright 2018 The dexon-consensus-core Authors
// This file is part of the dexon-consensus-core library.
//
// The dexon-consensus-core 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 dexon-consensus-core 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 dexon-consensus-core library. If not, see
// <http://www.gnu.org/licenses/>.
package simulation
import (
"context"
"encoding/json"
"fmt"
"io/ioutil"
"log"
"net"
"net/http"
"sync"
"time"
"github.com/dexon-foundation/dexon-consensus-core/core/types"
"github.com/dexon-foundation/dexon-consensus-core/simulation/config"
)
// PeerServer is the main object for maintaining peer list.
type PeerServer struct {
peers map[types.ValidatorID]string
peersMu sync.Mutex
peerTotalOrder PeerTotalOrder
peerTotalOrderMu sync.Mutex
verifiedLen uint64
}
// NewPeerServer returns a new peer server.
func NewPeerServer() *PeerServer {
return &PeerServer{
peers: make(map[types.ValidatorID]string),
peerTotalOrder: make(PeerTotalOrder),
}
}
// isValidator checks if vID is in p.peers. If peer server restarts but
// validators are not, it will cause panic if validators send message.
func (p *PeerServer) isValidator(vID types.ValidatorID) bool {
p.peersMu.Lock()
defer p.peersMu.Unlock()
_, exist := p.peers[vID]
return exist
}
// Run starts the peer server.
func (p *PeerServer) Run(configPath string) {
cfg, err := config.Read(configPath)
if err != nil {
panic(err)
}
resetHandler := func(w http.ResponseWriter, r *http.Request) {
p.peersMu.Lock()
defer p.peersMu.Unlock()
p.peers = make(map[types.ValidatorID]string)
log.Printf("Peer server has been reset.")
}
joinHandler := func(w http.ResponseWriter, r *http.Request) {
defer r.Body.Close()
idString := r.Header.Get("ID")
portString := r.Header.Get("PORT")
id := types.ValidatorID{}
id.UnmarshalText([]byte(idString))
p.peersMu.Lock()
defer p.peersMu.Unlock()
host, _, _ := net.SplitHostPort(r.RemoteAddr)
p.peers[id] = net.JoinHostPort(host, portString)
p.peerTotalOrder[id] = NewTotalOrderResult(id)
log.Printf("Peer %s joined from %s", id, p.peers[id])
if len(p.peers) == cfg.Validator.Num {
log.Println("All peers connected.")
}
w.WriteHeader(http.StatusOK)
}
peersHandler := func(w http.ResponseWriter, r *http.Request) {
p.peersMu.Lock()
defer p.peersMu.Unlock()
defer r.Body.Close()
if len(p.peers) != cfg.Validator.Num {
w.WriteHeader(http.StatusNotFound)
return
}
jsonText, err := json.Marshal(p.peers)
if err != nil {
w.WriteHeader(http.StatusInternalServerError)
return
}
w.WriteHeader(http.StatusOK)
w.Header().Set("Content-Type", "application/json")
w.Write(jsonText)
}
infoHandler := func(w http.ResponseWriter, r *http.Request) {
p.peersMu.Lock()
defer p.peersMu.Unlock()
defer r.Body.Close()
msg := InfoMessage{
Status: statusNormal,
Peers: p.peers,
}
if len(p.peers) < cfg.Validator.Num {
msg.Status = statusInit
}
// Determine msg.status.
if p.verifiedLen >= cfg.Validator.MaxBlock {
msg.Status = statusShutdown
}
jsonText, err := json.Marshal(msg)
if err != nil {
w.WriteHeader(http.StatusInternalServerError)
return
}
w.WriteHeader(http.StatusOK)
w.Header().Set("Content-Type", "application/json")
w.Write(jsonText)
}
deliveryHandler := func(w http.ResponseWriter, r *http.Request) {
defer r.Body.Close()
idString := r.Header.Get("ID")
body, err := ioutil.ReadAll(r.Body)
if err != nil {
w.WriteHeader(http.StatusBadRequest)
return
}
m := BlockList{}
if err := json.Unmarshal(body, &m); err != nil {
w.WriteHeader(http.StatusBadRequest)
return
}
id := types.ValidatorID{}
if err := id.UnmarshalText([]byte(idString)); err != nil {
w.WriteHeader(http.StatusBadRequest)
return
}
if !p.isValidator(id) {
w.WriteHeader(http.StatusForbidden)
return
}
w.WriteHeader(http.StatusOK)
p.peerTotalOrderMu.Lock()
defer p.peerTotalOrderMu.Unlock()
readyForVerify := p.peerTotalOrder[id].PushBlocks(m)
if !readyForVerify {
return
}
// Verify the total order result.
go func(id types.ValidatorID) {
p.peerTotalOrderMu.Lock()
defer p.peerTotalOrderMu.Unlock()
var correct bool
var length int
p.peerTotalOrder, correct, length = VerifyTotalOrder(id, p.peerTotalOrder)
if !correct {
log.Printf("The result of Total Ordering Algorithm has error.\n")
}
p.verifiedLen += uint64(length)
}(id)
}
stopServer := make(chan struct{})
messageHandler := func(w http.ResponseWriter, r *http.Request) {
defer r.Body.Close()
idString := r.Header.Get("ID")
id := types.ValidatorID{}
id.UnmarshalText([]byte(idString))
if !p.isValidator(id) {
w.WriteHeader(http.StatusForbidden)
return
}
body, err := ioutil.ReadAll(r.Body)
if err != nil {
w.WriteHeader(http.StatusBadRequest)
return
}
m := Message{}
if err := json.Unmarshal(body, &m); err != nil {
w.WriteHeader(http.StatusBadRequest)
return
}
switch m.Type {
case shutdownAck:
delete(p.peers, id)
log.Printf("%v shutdown, %d remains.\n", id, len(p.peers))
if len(p.peers) == 0 {
stopServer <- struct{}{}
}
break
case blockTimestamp:
msgs := []TimestampMessage{}
if err := json.Unmarshal(m.Payload, &msgs); err != nil {
w.WriteHeader(http.StatusBadRequest)
return
}
for _, msg := range msgs {
if ok := p.peerTotalOrder[id].PushTimestamp(msg); !ok {
w.WriteHeader(http.StatusBadRequest)
return
}
}
break
default:
w.WriteHeader(http.StatusBadRequest)
return
}
w.WriteHeader(http.StatusOK)
}
http.HandleFunc("/reset", resetHandler)
http.HandleFunc("/join", joinHandler)
http.HandleFunc("/peers", peersHandler)
http.HandleFunc("/info", infoHandler)
http.HandleFunc("/delivery", deliveryHandler)
http.HandleFunc("/message", messageHandler)
addr := fmt.Sprintf("0.0.0.0:%d", peerPort)
log.Printf("Peer server started at %s", addr)
server := &http.Server{Addr: addr}
go func() {
<-stopServer
LogStatus(p.peerTotalOrder)
log.Printf("Shutting down peerServer.\n")
ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
defer cancel()
if err := server.Shutdown(ctx); err != nil {
log.Printf("Error shutting down peerServer: %v\n", err)
}
}()
if err := server.ListenAndServe(); err != nil && err != http.ErrServerClosed {
log.Fatalf("Error starting server %v\n", err)
}
// Do not exit when we are in TCP node, since k8s will restart the pod and
// cause confusions.
if cfg.Networking.Type == config.NetworkTypeTCP {
select {}
}
}
