How to read data (xml) sent by server if it doesn't send new line - sockets

Question

Let's say we try to communicate with a server (XMPP) which sends back XML data. We can use
conn, err := net.Dial("tcp", s.Addr+":5222")
//...
r := bufio.NewReader(conn)
//...
s, err := s.R.ReadString(10) // to read a string
But there is one problem that the server doesn't send the \10 (newline) symbol. I also tried 12 but without any luck. Same goes for readLine function as it also relies on \10. So how do I read the data sent by server?
I tried using '>' as a delimiter and succeeded to receive only parts of the messages (predictable). I had an idea to loop while error is nil and use delimiter of '>' but it also didn't work.
My research shown that the last symbol of the message is really '>' (62) and there is not any anything else at the end.

Answer 1

Use an xml.Decoder to read stanzas from an XMPP stream.
conn, err := net.Dial("tcp", s.Addr+":5222")
if err != nil {
// handle error
}
dec := xml.NewDecoder(conn)
Use the decoder Token method to read the root document element and to skip over character data between stanzas:
func readStartElement(dec *xml.Decoder) (xml.StartElement, error) {
for {
t, err := dec.Token()
if err != nil {
return xml.StartElement{}, err
}
switch t := t.(type) {
case xml.StartElement:
return t, nil
}
}
}
Use the decoder DecodeElement method to read a stanza:
func readStanza(dec *xml.Decoder) (interface{}, error) {
se, err := readStartElement(dec)
if err != nil {
return nil, err
}
var v interface{}
switch se.Name.Space + " " + se.Name.Local {
case "jabber:client message":
v = &jabberMessage{} // jabberMessage is struct type defined by app for messages
// Add other stanza types here.
default:
v = &struct{}{}
}
if err := dec.DecodeElement(v, &se); err != nil {
return nil, err
}
return v, nil
}
Type switch on the return value from readStanza to handle the different types of received stanzas.
A client reads stanzas synchronously. Here's rough outline (ignoring authentication, etc).
conn, err := net.Dial("tcp", s.Addr+":5222")
if err != nil {
// handle error
}
dec := xml.NewDecoder(conn)
// read and discard root element
_, err := readStartElement(dec)
if err != nil {
// handle error
}
// read stanzas
for {
v, err := readStanza(dec)
if err != nil {
// handle error
// must break out of loop on error
}
switch v := v.(type) {
case *jabberMessage:
// handle message
case *someOtherStanzaType:
// handle other stanza types
// ... and so on
}
}