数据是任何业务不可脱离的基础，对于牵涉众多数据的金融行业更为重要，如何保证业务数据传输时的完整对于金融业的App极其重要。本次的代码是简单的测试数据流的完整性
type Packet struct {
header Header
body []byte
tailer Tailer
}
type Header struct {
bodylen uint32
msgtype uint32
add uint32
userdata uint32
}
type Tailer struct {
checkcode uint32
}
func TestPacketSize(t *testing.T) {
datapoint := new(Packet)
log.Println("packet size is ", unsafe.Sizeof(datapoint))
var data Packet
log.Println("packet size is ", unsafe.Sizeof(data)) //body []byte default size is 24
p := NewPacket(1, []byte("this is test data"))
log.Println("p size is ", unsafe.Sizeof(p)) // 8
log.Println("p.header size is ", unsafe.Sizeof(p.header)) //8 add 12 userdata 16
log.Println("p.body length is ", len(p.body)) //17
log.Println("p.header.bodylen is ", p.header.bodylen) //17
}
func TestIsComplete(t *testing.T) {
p := NewPacket(1, []byte("this is test data"))
log.Println("p size is ", unsafe.Sizeof(p))
log.Println("p is ", p)
buf := PacketData(1, []byte("this is test data"))
log.Println("buf size is ", unsafe.Sizeof(buf))
log.Println("buf is ", buf)
checkbuf := PacketData(p.header.msgtype, p.body)
out := IsComplete(buf, checkbuf)
if len(out) == 0 {
log.Println("there are some error of this packet data")
} else {
log.Println("out length is ", len(out))
log.Println("out is ", out)
}
var outbuf []byte
log.Println("outbuf length is ", len(outbuf))
log.Println("outbuf is ", outbuf)
}
func IsComplete(buf, checkbuf []byte) (outbuf []byte) {
length := len(buf)
if length != len(checkbuf) {
log.Println("data is not complete")
return
} else {
if buf[length-1] != checkbuf[length-1] {
log.Println("checkcode is wrong")
return
} else {
for i := 0; i < length; i++ {
if buf[i] != checkbuf[i] {
log.Println("data may be complete,but it's wrong data")
return
}
}
outbuf = buf[16 : length-4]
return
}
}
}
func NewPacket(msg uint32, b []byte) *Packet {
length := len(b)
log.Println("body length is ", length) //17
return &Packet{
header: Header{
msgtype: msg,
bodylen: uint32(length),
add: 1,
userdata: 2,
},
body: b,
}
}
func GenerateCheckCode(indata []byte) (out uint32) {
for _, v := range indata {
out += uint32(v)
}
out = out % 256
return
}
func PacketData(msgtype uint32, data []byte) (buf []byte) {
header := make([]byte, 16)
binary.BigEndian.PutUint32(header[0:4], msgtype)
bodylen := uint32(len(data))
binary.BigEndian.PutUint32(header[4:8], bodylen)
userdata1 := uint32(1)
binary.BigEndian.PutUint32(header[8:12], userdata1)
userdata2 := uint32(2)
binary.BigEndian.PutUint32(header[12:16], userdata2)
buf = make([]byte, bodylen+20)
copy(buf[0:16], header[0:16])
copy(buf[16:], data[:])
tail := make([]byte, 4)
check := GenerateCheckCode(buf)
binary.BigEndian.PutUint32(tail[0:4], check)
copy(buf[bodylen+16:], tail[:])
return
}
运行结果
