1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
|
// 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 (
"encoding/json"
"fmt"
"io/ioutil"
"math/rand"
"net/http"
"runtime"
"strings"
"sync"
"time"
"github.com/dexon-foundation/dexon-consensus-core/core"
"github.com/dexon-foundation/dexon-consensus-core/core/types"
)
// TCPNetwork implements the core.Network interface.
type TCPNetwork struct {
local bool
port int
endpoint core.Endpoint
peerServer string
endpointMutex sync.RWMutex
endpoints map[types.ValidatorID]string
recieveChan chan interface{}
}
// NewTCPNetwork returns pointer to a new Network instance.
func NewTCPNetwork(local bool, peerServer string) *TCPNetwork {
port := 1024 + rand.Int()%1024
if !local {
port = peerPort
}
return &TCPNetwork{
local: local,
peerServer: peerServer,
port: port,
endpoints: make(map[types.ValidatorID]string),
recieveChan: make(chan interface{}, msgBufferSize),
}
}
// Start starts the http server for accepting message.
func (n *TCPNetwork) Start() {
addr := fmt.Sprintf("0.0.0.0:%d", n.port)
server := &http.Server{
Addr: addr,
Handler: n,
}
fmt.Printf("Validator started at %s\n", addr)
server.ListenAndServe()
}
// NumPeers returns the number of peers in the network.
func (n *TCPNetwork) NumPeers() int {
n.endpointMutex.Lock()
defer n.endpointMutex.Unlock()
return len(n.endpoints)
}
// ServerHTTP implements the http.Handler interface.
func (n *TCPNetwork) ServeHTTP(w http.ResponseWriter, r *http.Request) {
defer r.Body.Close()
body, err := ioutil.ReadAll(r.Body)
if err != nil {
w.WriteHeader(http.StatusBadRequest)
return
}
m := struct {
Type string `json:"type"`
Payload json.RawMessage `json:"payload"`
}{}
if err := json.Unmarshal(body, &m); err != nil {
w.WriteHeader(http.StatusBadRequest)
return
}
switch m.Type {
case "block":
block := &types.Block{}
if err := json.Unmarshal(m.Payload, block); err != nil {
w.WriteHeader(http.StatusBadRequest)
return
}
n.recieveChan <- block
default:
w.WriteHeader(http.StatusBadRequest)
return
}
}
// Join allow a client to join the network. It reutnrs a interface{} channel for
// the client to recieve information.
func (n *TCPNetwork) Join(endpoint core.Endpoint) chan interface{} {
n.endpointMutex.Lock()
defer n.endpointMutex.Unlock()
n.endpoint = endpoint
joinURL := fmt.Sprintf("http://%s:%d/join", n.peerServer, peerPort)
peersURL := fmt.Sprintf("http://%s:%d/peers", n.peerServer, peerPort)
client := &http.Client{Timeout: 5 * time.Second}
// Join the peer list.
for {
time.Sleep(time.Second)
req, err := http.NewRequest(http.MethodGet, joinURL, nil)
if err != nil {
continue
}
req.Header.Add("ID", endpoint.GetID().String())
req.Header.Add("PORT", fmt.Sprintf("%d", n.port))
resp, err := client.Do(req)
if err == nil && resp.StatusCode == http.StatusOK {
break
}
}
var peerList map[types.ValidatorID]string
// Wait for the server to collect all validators and return a list.
for {
time.Sleep(time.Second)
req, err := http.NewRequest(http.MethodGet, peersURL, nil)
if err != nil {
fmt.Println(err)
continue
}
req.Header.Add("ID", endpoint.GetID().String())
resp, err := client.Do(req)
if err != nil || resp.StatusCode != http.StatusOK {
continue
}
defer resp.Body.Close()
body, err := ioutil.ReadAll(resp.Body)
if err := json.Unmarshal(body, &peerList); err != nil {
fmt.Printf("error: %v", err)
continue
}
break
}
for key, val := range peerList {
n.endpoints[key] = val
}
return n.recieveChan
}
// Send sends a msg to another client.
func (n *TCPNetwork) Send(destID types.ValidatorID, msg interface{}) {
clientAddr, exists := n.endpoints[destID]
if !exists {
return
}
message := struct {
Type string `json:"type"`
Payload interface{} `json:"payload"`
}{}
switch v := msg.(type) {
case *types.Block:
message.Type = "block"
message.Payload = v
default:
fmt.Println("error: invalid message type")
return
}
messageJSON, err := json.Marshal(message)
if err != nil {
fmt.Printf("error: failed to marshal json: %v\n%+v\n", err, message)
return
}
msgURL := fmt.Sprintf("http://%s/msg", clientAddr)
go func() {
retries := 3
client := &http.Client{Timeout: 5 * time.Second}
for i := 0; i < retries; i++ {
req, err := http.NewRequest(
http.MethodPost, msgURL, strings.NewReader(string(messageJSON)))
if err != nil {
continue
}
req.Header.Add("ID", n.endpoint.GetID().String())
resp, err := client.Do(req)
if err == nil && resp.StatusCode == http.StatusOK {
runtime.Goexit()
}
time.Sleep(1 * time.Second)
}
fmt.Printf("failed to send message: %v\n", msg)
}()
}
// BroadcastBlock broadcast blocks into the network.
func (n *TCPNetwork) BroadcastBlock(block *types.Block) {
for endpoint := range n.endpoints {
n.Send(endpoint, block.Clone())
}
}
|