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
| package main
import (
"os"
"fmt"
"net"
"time"
"math/rand"
"encoding/json"
"bufio"
"hash/crc32"
"sync"
)
//数据包类型
const (
HEART_BEAT_PACKET = 0x00
REPORT_PACKET = 0x01
)
//默认的服务器地址
var (
server = "127.0.0.1:9876"
)
//数据包
type Packet struct {
PacketType byte
PacketContent []byte
}
//心跳包
type HeartPacket struct {
Version string`json:"version"`
Timestamp int64`json:"timestamp"`
}
//数据包
type ReportPacket struct {
Content string`json:"content"`
Rand int`json:"rand"`
Timestamp int64`json:"timestamp"`
}
//客户端对象
type TcpClient struct {
connection *net.TCPConn
hawkServer *net.TCPAddr
stopChan chan struct{}
}
func main() {
//拿到服务器地址信息
hawkServer,err := net.ResolveTCPAddr("tcp", server)
if err != nil {
fmt.Printf("hawk server [%s] resolve error: [%s]",server,err.Error())
os.Exit(1)
}
//连接服务器
connection,err := net.DialTCP("tcp",nil,hawkServer)
if err != nil {
fmt.Printf("connect to hawk server error: [%s]",err.Error())
os.Exit(1)
}
client := &TcpClient{
connection:connection,
hawkServer:hawkServer,
stopChan:make(chan struct{}),
}
//启动接收
go client.receivePackets()
//发送心跳的goroutine
go func() {
heartBeatTick := time.Tick(2 * time.Second)
for{
select {
case <-heartBeatTick:
client.sendHeartPacket()
case <-client.stopChan:
return
}
}
}()
//测试用的，开300个goroutine每秒发送一个包
for i:=0;i<300;i++ {
go func() {
sendTimer := time.After(1 * time.Second)
for{
select {
case <-sendTimer:
client.sendReportPacket()
sendTimer = time.After(1 * time.Second)
case <-client.stopChan:
return
}
}
}()
}
//等待退出
<-client.stopChan
}
// 接收数据包
func (client *TcpClient)receivePackets() {
reader := bufio.NewReader(client.connection)
for {
//承接上面说的服务器端的偷懒，我这里读也只是以\n为界限来读区分包
msg, err := reader.ReadString('\n')
if err != nil {
//在这里也请处理如果服务器关闭时的异常
close(client.stopChan)
break
}
fmt.Print(msg)
}
}
//发送数据包
//仔细看代码其实这里做了两次json的序列化，有一次其实是不需要的
func (client *TcpClient)sendReportPacket() {
reportPacket := ReportPacket{
Content:getRandString(),
Timestamp:time.Now().Unix(),
Rand:rand.Int(),
}
packetBytes,err := json.Marshal(reportPacket)
if err!=nil{
fmt.Println(err.Error())
}
//这一次其实可以不需要，在封包的地方把类型和数据传进去即可
packet := Packet{
PacketType:REPORT_PACKET,
PacketContent:packetBytes,
}
sendBytes,err := json.Marshal(packet)
if err!=nil{
fmt.Println(err.Error())
}
//发送
client.connection.Write(EnPackSendData(sendBytes))
fmt.Println("Send metric data success!")
}
//使用的协议与服务器端保持一致
func EnPackSendData(sendBytes []byte) []byte {
packetLength := len(sendBytes) + 8
result := make([]byte,packetLength)
result[0] = 0xFF
result[1] = 0xFF
result[2] = byte(uint16(len(sendBytes)) >> 8)
result[3] = byte(uint16(len(sendBytes)) & 0xFF)
copy(result[4:],sendBytes)
sendCrc := crc32.ChecksumIEEE(sendBytes)
result[packetLength-4] = byte(sendCrc >> 24)
result[packetLength-3] = byte(sendCrc >> 16 & 0xFF)
result[packetLength-2] = 0xFF
result[packetLength-1] = 0xFE
fmt.Println(result)
return result
}
//发送心跳包，与发送数据包一样
func (client *TcpClient)sendHeartPacket() {
heartPacket := HeartPacket{
Version:"1.0",
Timestamp:time.Now().Unix(),
}
packetBytes,err := json.Marshal(heartPacket)
if err!=nil{
fmt.Println(err.Error())
}
packet := Packet{
PacketType:HEART_BEAT_PACKET,
PacketContent:packetBytes,
}
sendBytes,err := json.Marshal(packet)
if err!=nil{
fmt.Println(err.Error())
}
client.connection.Write(EnPackSendData(sendBytes))
fmt.Println("Send heartbeat data success!")
}
//拿一串随机字符
func getRandString()string {
length := rand.Intn(50)
strBytes := make([]byte,length)
for i:=0;i<length;i++ {
strBytes[i] = byte(rand.Intn(26) + 97)
}
return string(strBytes)
}
|