144 lines
2.7 KiB
Go
144 lines
2.7 KiB
Go
// Copyright 2018 The go-zeromq Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
package zmq4
|
|
|
|
import (
|
|
"bytes"
|
|
"fmt"
|
|
"io"
|
|
)
|
|
|
|
type MsgType byte
|
|
|
|
const (
|
|
UsrMsg MsgType = 0
|
|
CmdMsg MsgType = 1
|
|
)
|
|
|
|
// Msg is a ZMTP message, possibly composed of multiple frames.
|
|
type Msg struct {
|
|
Frames [][]byte
|
|
Type MsgType
|
|
multipart bool
|
|
err error
|
|
}
|
|
|
|
func NewMsg(frame []byte) Msg {
|
|
return Msg{Frames: [][]byte{frame}}
|
|
}
|
|
|
|
func NewMsgFrom(frames ...[]byte) Msg {
|
|
return Msg{Frames: frames}
|
|
}
|
|
|
|
func NewMsgString(frame string) Msg {
|
|
return NewMsg([]byte(frame))
|
|
}
|
|
|
|
func NewMsgFromString(frames []string) Msg {
|
|
msg := Msg{Frames: make([][]byte, len(frames))}
|
|
for i, frame := range frames {
|
|
msg.Frames[i] = append(msg.Frames[i], []byte(frame)...)
|
|
}
|
|
return msg
|
|
}
|
|
|
|
func (msg Msg) isCmd() bool {
|
|
return msg.Type == CmdMsg
|
|
}
|
|
|
|
func (msg Msg) Err() error {
|
|
return msg.err
|
|
}
|
|
|
|
// Bytes returns the concatenated content of all its frames.
|
|
func (msg Msg) Bytes() []byte {
|
|
buf := make([]byte, 0, msg.size())
|
|
for _, frame := range msg.Frames {
|
|
buf = append(buf, frame...)
|
|
}
|
|
return buf
|
|
}
|
|
|
|
func (msg Msg) size() int {
|
|
n := 0
|
|
for _, frame := range msg.Frames {
|
|
n += len(frame)
|
|
}
|
|
return n
|
|
}
|
|
|
|
func (msg Msg) String() string {
|
|
buf := new(bytes.Buffer)
|
|
buf.WriteString("Msg{Frames:{")
|
|
for i, frame := range msg.Frames {
|
|
if i > 0 {
|
|
buf.WriteString(", ")
|
|
}
|
|
fmt.Fprintf(buf, "%q", frame)
|
|
}
|
|
buf.WriteString("}}")
|
|
return buf.String()
|
|
}
|
|
|
|
func (msg Msg) Clone() Msg {
|
|
o := Msg{Frames: make([][]byte, len(msg.Frames))}
|
|
for i, frame := range msg.Frames {
|
|
o.Frames[i] = make([]byte, len(frame))
|
|
copy(o.Frames[i], frame)
|
|
}
|
|
return o
|
|
}
|
|
|
|
// Cmd is a ZMTP Cmd as per:
|
|
//
|
|
// https://rfc.zeromq.org/spec:23/ZMTP/#formal-grammar
|
|
type Cmd struct {
|
|
Name string
|
|
Body []byte
|
|
}
|
|
|
|
func (cmd *Cmd) unmarshalZMTP(data []byte) error {
|
|
if len(data) == 0 {
|
|
return io.ErrUnexpectedEOF
|
|
}
|
|
n := int(data[0])
|
|
if n > len(data)-1 {
|
|
return ErrBadCmd
|
|
}
|
|
cmd.Name = string(data[1 : n+1])
|
|
cmd.Body = data[n+1:]
|
|
return nil
|
|
}
|
|
|
|
func (cmd *Cmd) marshalZMTP() ([]byte, error) {
|
|
n := len(cmd.Name)
|
|
if n > 255 {
|
|
return nil, ErrBadCmd
|
|
}
|
|
|
|
buf := make([]byte, 0, 1+n+len(cmd.Body))
|
|
buf = append(buf, byte(n))
|
|
buf = append(buf, []byte(cmd.Name)...)
|
|
buf = append(buf, cmd.Body...)
|
|
return buf, nil
|
|
}
|
|
|
|
// ZMTP commands as per:
|
|
//
|
|
// https://rfc.zeromq.org/spec:23/ZMTP/#commands
|
|
const (
|
|
CmdCancel = "CANCEL"
|
|
CmdError = "ERROR"
|
|
CmdHello = "HELLO"
|
|
CmdInitiate = "INITIATE"
|
|
CmdPing = "PING"
|
|
CmdPong = "PONG"
|
|
CmdReady = "READY"
|
|
CmdSubscribe = "SUBSCRIBE"
|
|
CmdUnsubscribe = "UNSUBSCRIBE"
|
|
CmdWelcome = "WELCOME"
|
|
)
|