robocar-steering/vendor/github.com/eclipse/paho.mqtt.golang/packets/suback.go

61 lines
1.2 KiB
Go

package packets
import (
"bytes"
"fmt"
"io"
)
//SubackPacket is an internal representation of the fields of the
//Suback MQTT packet
type SubackPacket struct {
FixedHeader
MessageID uint16
ReturnCodes []byte
}
func (sa *SubackPacket) String() string {
str := fmt.Sprintf("%s", sa.FixedHeader)
str += " "
str += fmt.Sprintf("MessageID: %d", sa.MessageID)
return str
}
func (sa *SubackPacket) Write(w io.Writer) error {
var body bytes.Buffer
var err error
body.Write(encodeUint16(sa.MessageID))
body.Write(sa.ReturnCodes)
sa.FixedHeader.RemainingLength = body.Len()
packet := sa.FixedHeader.pack()
packet.Write(body.Bytes())
_, err = packet.WriteTo(w)
return err
}
//Unpack decodes the details of a ControlPacket after the fixed
//header has been read
func (sa *SubackPacket) Unpack(b io.Reader) error {
var qosBuffer bytes.Buffer
var err error
sa.MessageID, err = decodeUint16(b)
if err != nil {
return err
}
_, err = qosBuffer.ReadFrom(b)
if err != nil {
return err
}
sa.ReturnCodes = qosBuffer.Bytes()
return nil
}
//Details returns a Details struct containing the Qos and
//MessageID of this ControlPacket
func (sa *SubackPacket) Details() Details {
return Details{Qos: 0, MessageID: sa.MessageID}
}