Refactor parsing / improve typing

auth.go

@@ -32,37 +32,72 @@ func authPlain(socket io.ReadWriter, decoder *xml.Decoder, user string, password
 	fmt.Fprintf(socket, "<auth xmlns='%s' mechanism='PLAIN'>%s</auth>", nsSASL, enc)
 
 	// Next message should be either success or failure.
-	name, val, err := next(decoder)
+	val, err := next(decoder)
 	if err != nil {
 		return err
 	}
 
 	switch v := val.(type) {
-	case *saslSuccess:
-	case *saslFailure:
+	case *SASLSuccess:
+	case *SASLFailure:
 		// v.Any is type of sub-element in failure, which gives a description of what failed.
 		return errors.New("auth failure: " + v.Any.Local)
 	default:
-		return errors.New("expected success or failure, got " + name.Local + " in " + name.Space)
+		return errors.New("expected SASL success or failure, got " + v.Name())
 	}
 	return err
 }
 
-// XMPP Packet Parsing
 type saslMechanisms struct {
 	XMLName   xml.Name `xml:"urn:ietf:params:xml:ns:xmpp-sasl mechanisms"`
 	Mechanism []string `xml:"mechanism"`
 }
 
-type saslSuccess struct {
+// ============================================================================
+// SASLSuccess
+
+type SASLSuccess struct {
 	XMLName xml.Name `xml:"urn:ietf:params:xml:ns:xmpp-sasl success"`
 }
 
-type saslFailure struct {
+func (SASLSuccess) Name() string {
+	return "sasl:success"
+}
+
+type saslSuccessDecoder struct{}
+
+var saslSuccess saslSuccessDecoder
+
+func (saslSuccessDecoder) decode(p *xml.Decoder, se xml.StartElement) (SASLSuccess, error) {
+	var packet SASLSuccess
+	err := p.DecodeElement(&packet, &se)
+	return packet, err
+}
+
+// ============================================================================
+// SASLFailure
+
+type SASLFailure struct {
 	XMLName xml.Name `xml:"urn:ietf:params:xml:ns:xmpp-sasl failure"`
 	Any     xml.Name // error reason is a subelement
 }
 
+func (SASLFailure) Name() string {
+	return "sasl:failure"
+}
+
+type saslFailureDecoder struct{}
+
+var saslFailure saslFailureDecoder
+
+func (saslFailureDecoder) decode(p *xml.Decoder, se xml.StartElement) (SASLFailure, error) {
+	var packet SASLFailure
+	err := p.DecodeElement(&packet, &se)
+	return packet, err
+}
+
+// ============================================================================
+
 type auth struct {
 	XMLName   xml.Name `xml:"urn:ietf:params:xml:ns:xmpp-sasl auth"`
 	Mechanism string   `xml:"mecanism,attr"`

client.go

@@ -108,7 +108,7 @@ func (c *Client) Connect() (*Session, error) {
 
 func (c *Client) recv(receiver chan<- interface{}) (err error) {
 	for {
-		_, val, err := next(c.Session.decoder)
+		val, err := next(c.Session.decoder)
 		if err != nil {
 			return err
 		}

client_test.go

@@ -163,7 +163,7 @@ func bind(t *testing.T, c net.Conn, decoder *xml.Decoder) {
 		return
 	}
 
-	iq := &ClientIQ{}
+	iq := &IQ{}
 	// Decode element into pointer storage
 	if err = decoder.DecodeElement(&iq, &se); err != nil {
 		t.Errorf("cannot decode bind iq: %s", err)

cmd/xmpp_component/xmpp_component.go

@@ -11,11 +11,18 @@ func main() {
 	component.Connect("localhost:8888")
 
 	for {
-		_, packet, err := component.ReadPacket()
+		packet, err := component.ReadPacket()
 		if err != nil {
 			fmt.Println("read error", err)
 			return
 		}
-		fmt.Println("Packet received: ", packet)
+
+		switch p := packet.(type) {
+		case xmpp.IQ:
+			fmt.Println("IQ received: ", p)
+			fmt.Println("IQ type:", p.Type)
+		default:
+			fmt.Println("Packet unhandled packet:", packet)
+		}
 	}
 }

cmd/xmpp_echo/xmpp_echo.go

@@ -31,9 +31,9 @@ func main() {
 	// Iterator to receive packets coming from our XMPP connection
 	for packet := range client.Recv() {
 		switch packet := packet.(type) {
-		case *xmpp.ClientMessage:
+		case *xmpp.Message:
 			fmt.Fprintf(os.Stdout, "Body = %s - from = %s\n", packet.Body, packet.From)
-			reply := xmpp.ClientMessage{PacketAttrs: xmpp.PacketAttrs{To: packet.From}, Body: packet.Body}
+			reply := xmpp.Message{PacketAttrs: xmpp.PacketAttrs{To: packet.From}, Body: packet.Body}
 			client.Send(reply.XMPPFormat())
 		default:
 			fmt.Fprintf(os.Stdout, "Ignoring packet: %T\n", packet)

cmd/xmpp_jukebox/xmpp_jukebox.go

@@ -40,11 +40,11 @@ func main() {
 	for packet := range client.Recv() {
 
 		switch packet := packet.(type) {
-		case *xmpp.ClientMessage:
+		case *xmpp.Message:
 			processMessage(client, p, packet)
-		case *xmpp.ClientIQ:
+		case *xmpp.IQ:
 			processIq(client, p, packet)
-		case *xmpp.ClientPresence:
+		case *xmpp.Presence:
 			// Do nothing with received presence
 		default:
 			fmt.Fprintf(os.Stdout, "Ignoring packet: %T\n", packet)
@@ -52,7 +52,7 @@ func main() {
 	}
 }
 
-func processMessage(client *xmpp.Client, p *mpg123.Player, packet *xmpp.ClientMessage) {
+func processMessage(client *xmpp.Client, p *mpg123.Player, packet *xmpp.Message) {
 	command := strings.Trim(packet.Body, " ")
 	if command == "stop" {
 		p.Stop()
@@ -62,7 +62,7 @@ func processMessage(client *xmpp.Client, p *mpg123.Player, packet *xmpp.ClientMe
 	}
 }
 
-func processIq(client *xmpp.Client, p *mpg123.Player, packet *xmpp.ClientIQ) {
+func processIq(client *xmpp.Client, p *mpg123.Player, packet *xmpp.IQ) {
 	switch payload := packet.Payload.(type) {
 	// We support IOT Control IQ
 	case *iot.ControlSet:
@@ -76,7 +76,7 @@ func processIq(client *xmpp.Client, p *mpg123.Player, packet *xmpp.ClientIQ) {
 
 		playSCURL(p, url)
 		setResponse := new(iot.ControlSetResponse)
-		reply := xmpp.ClientIQ{PacketAttrs: xmpp.PacketAttrs{To: packet.From, Type: "result", Id: packet.Id}, Payload: setResponse}
+		reply := xmpp.IQ{PacketAttrs: xmpp.PacketAttrs{To: packet.From, Type: "result", Id: packet.Id}, Payload: setResponse}
 		client.Send(reply.XMPPFormat())
 		// TODO add Soundclound artist / title retrieval
 		sendUserTune(client, "Radiohead", "Spectre")

component.go

@@ -72,7 +72,7 @@ func (c *Component) Connect(connStr string) error {
 	}
 
 	// 4. Check server response for authentication
-	name, val, err := next(c.decoder)
+	val, err := next(c.decoder)
 	if err != nil {
 		return err
 	}
@@ -83,20 +83,34 @@ func (c *Component) Connect(connStr string) error {
 	case *Handshake:
 		return nil
 	default:
-		return errors.New("unexpected packet, got " + name.Local + " in " + name.Space)
+		return errors.New("unexpected packet, got " + v.Name())
 	}
 	panic("unreachable")
 }
 
 // ReadPacket reads next incoming XMPP packet
 // TODO use defined interface Packet
-func (c *Component) ReadPacket() (xml.Name, interface{}, error) {
+func (c *Component) ReadPacket() (Packet, error) {
 	return next(c.decoder)
 }
 
 // ============================================================================
-// XMPP packets struct
+// Handshake Packet
 
 type Handshake struct {
 	XMLName xml.Name `xml:"jabber:component:accept handshake"`
 }
+
+func (Handshake) Name() string {
+	return "component:handshake"
+}
+
+type handshakeDecoder struct{}
+
+var handshake handshakeDecoder
+
+func (handshakeDecoder) decode(p *xml.Decoder, se xml.StartElement) (Handshake, error) {
+	var packet Handshake
+	err := p.DecodeElement(&packet, &se)
+	return packet, err
+}

iq.go

@@ -7,9 +7,11 @@ import (
 	"fluux.io/xmpp/iot"
 )
 
-// info/query
-type ClientIQ struct {
-	XMLName xml.Name `xml:"jabber:client iq"`
+// ============================================================================
+// IQ Packet
+
+type IQ struct { // Info/Query
+	XMLName xml.Name `xml:"iq"`
 	PacketAttrs
 	Payload IQPayload `xml:",omitempty"`
 	RawXML  string    `xml:",innerxml"`
@@ -17,12 +19,26 @@ type ClientIQ struct {
 	// 	Error   clientError
 }
 
+func (IQ) Name() string {
+	return "iq"
+}
+
+type iqDecoder struct{}
+
+var iq iqDecoder
+
+func (iqDecoder) decode(p *xml.Decoder, se xml.StartElement) (IQ, error) {
+	var packet IQ
+	err := p.DecodeElement(&packet, &se)
+	return packet, err
+}
+
 type IQPayload interface {
 	IsIQPayload()
 }
 
 // UnmarshalXML implements custom parsing for IQs
-func (iq *ClientIQ) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error {
+func (iq *IQ) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error {
 	iq.XMLName = start.Name
 	// Extract IQ attributes
 	for _, attr := range start.Attr {
@@ -80,7 +96,7 @@ func (iq *ClientIQ) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error {
 
 // XMPPFormat returns the string representation of the XMPP packet.
 // TODO: Should I simply rely on xml.Marshal ?
-func (iq *ClientIQ) XMPPFormat() string {
+func (iq *IQ) XMPPFormat() string {
 	if iq.Payload != nil {
 		var payload []byte
 		var err error

iq_test.go

@@ -10,14 +10,14 @@ func TestUnmarshalIqs(t *testing.T) {
 	//var cs1 = new(iot.ControlSet)
 	var tests = []struct {
 		iqString string
-		parsedIQ ClientIQ
+		parsedIQ IQ
 	}{
-		{"<iq id=\"1\" type=\"set\" to=\"test@localhost\"/>", ClientIQ{XMLName: xml.Name{Space: "", Local: "iq"}, PacketAttrs: PacketAttrs{To: "test@localhost", Type: "set", Id: "1"}}},
-		//{"<iq xmlns=\"jabber:client\" id=\"2\" type=\"set\" to=\"test@localhost\" from=\"server\"><set xmlns=\"urn:xmpp:iot:control\"/></iq>", ClientIQ{XMLName: xml.Name{Space: "jabber:client", Local: "iq"}, PacketAttrs: PacketAttrs{To: "test@localhost", From: "server", Type: "set", Id: "2"}, Payload: cs1}},
+		{"<iq id=\"1\" type=\"set\" to=\"test@localhost\"/>", IQ{XMLName: xml.Name{Space: "", Local: "iq"}, PacketAttrs: PacketAttrs{To: "test@localhost", Type: "set", Id: "1"}}},
+		//{"<iq xmlns=\"jabber:client\" id=\"2\" type=\"set\" to=\"test@localhost\" from=\"server\"><set xmlns=\"urn:xmpp:iot:control\"/></iq>", IQ{XMLName: xml.Name{Space: "jabber:client", Local: "iq"}, PacketAttrs: PacketAttrs{To: "test@localhost", From: "server", Type: "set", Id: "2"}, Payload: cs1}},
 	}
 
 	for _, test := range tests {
-		var parsedIQ = new(ClientIQ)
+		var parsedIQ = new(IQ)
 		err := xml.Unmarshal([]byte(test.iqString), parsedIQ)
 		if err != nil {
 			t.Errorf("Unmarshal(%s) returned error", test.iqString)

message.go

@@ -5,20 +5,36 @@ import (
 	"fmt"
 )
 
-// XMPP Packet Parsing
-type ClientMessage struct {
-	XMLName xml.Name `xml:"jabber:client message"`
+// ============================================================================
+// Message Packet
+
+type Message struct {
+	XMLName xml.Name `xml:"message"`
 	PacketAttrs
 	Subject string `xml:"subject,omitempty"`
 	Body    string `xml:"body,omitempty"`
 	Thread  string `xml:"thread,omitempty"`
 }
 
-// TODO: Func new message to create an empty message structure without the XML tag matching elements
+func (Message) Name() string {
+	return "message"
+}
 
-func (message *ClientMessage) XMPPFormat() string {
+type messageDecoder struct{}
+
+var message messageDecoder
+
+func (messageDecoder) decode(p *xml.Decoder, se xml.StartElement) (Message, error) {
+	var packet Message
+	err := p.DecodeElement(&packet, &se)
+	return packet, err
+}
+
+func (msg *Message) XMPPFormat() string {
 	return fmt.Sprintf("<message to='%s' type='chat' xml:lang='en'>"+
 		"<body>%s</body></message>",
-		message.To,
-		xmlEscape(message.Body))
+		msg.To,
+		xmlEscape(msg.Body))
 }
+
+// TODO: Func new message to create an empty message structure without the XML tag matching elements

packet.go

@@ -1,5 +1,9 @@
 package xmpp // import "fluux.io/xmpp"
 
+type Packet interface {
+	Name() string
+}
+
 // PacketAttrs represents the common structure for base XMPP packets.
 type PacketAttrs struct {
 	Id   string `xml:"id,attr,omitempty"`

parser.go

@@ -63,87 +63,71 @@ func nextStart(p *xml.Decoder) (xml.StartElement, error) {
 // next scans XML token stream for next element and then assign a structure to decode
 // that elements.
 // TODO Use an interface to return packets interface xmppDecoder
-func next(p *xml.Decoder) (xml.Name, interface{}, error) {
-	// Read start element to find out what type we want.
+func next(p *xml.Decoder) (Packet, error) {
+	// Read start element to find out how we want to parse the XMPP packet
 	se, err := nextStart(p)
 	if err != nil {
-		return xml.Name{}, nil, err
+		return nil, err
 	}
 
-	// Put it in an interface and allocate the right structure
-	var nv interface{}
 	// TODO: general case = Parse IQ / presence / message => split SASL Stream and component cases
 	switch se.Name.Space {
 	case NSStream:
-		if nv, err = decodeStream(se); err != nil {
-			return xml.Name{}, nil, err
-		}
+		return decodeStream(p, se)
 	case nsSASL:
-		if nv, err = decodeSASL(se); err != nil {
-			return xml.Name{}, nil, err
-		}
+		return decodeSASL(p, se)
 	case NSClient:
-		if nv, err = decodeClient(se); err != nil {
-			return xml.Name{}, nil, err
-		}
+		return decodeClient(p, se)
 	case NSComponent:
-		if nv, err = decodeComponent(se); err != nil {
-			return xml.Name{}, nil, err
-		}
+		return decodeComponent(p, se)
 	default:
-		return xml.Name{}, nil, errors.New("unknown namespace " +
+		return nil, errors.New("unknown namespace " +
 			se.Name.Space + " <" + se.Name.Local + "/>")
 	}
-
-	// Decode element into pointer storage
-	if err = p.DecodeElement(nv, &se); err != nil {
-		return xml.Name{}, nil, err
-	}
-	return se.Name, nv, err
 }
 
-func decodeStream(se xml.StartElement) (interface{}, error) {
+func decodeStream(p *xml.Decoder, se xml.StartElement) (Packet, error) {
 	switch se.Name.Local {
 	case "error":
-		return &StreamError{}, nil
+		return streamError.decode(p, se)
 	default:
 		return nil, errors.New("unexpected XMPP packet " +
 			se.Name.Space + " <" + se.Name.Local + "/>")
 	}
 }
 
-func decodeSASL(se xml.StartElement) (interface{}, error) {
+func decodeSASL(p *xml.Decoder, se xml.StartElement) (Packet, error) {
 	switch se.Name.Local {
 	case "success":
-		return &saslSuccess{}, nil
+		return saslSuccess.decode(p, se)
 	case "failure":
-		return &saslFailure{}, nil
+		return saslFailure.decode(p, se)
 	default:
 		return nil, errors.New("unexpected XMPP packet " +
 			se.Name.Space + " <" + se.Name.Local + "/>")
 	}
 }
 
-func decodeClient(se xml.StartElement) (interface{}, error) {
+func decodeClient(p *xml.Decoder, se xml.StartElement) (Packet, error) {
 	switch se.Name.Local {
 	case "message":
-		return &ClientMessage{}, nil
+		return message.decode(p, se)
 	case "presence":
-		return &ClientPresence{}, nil
+		return presence.decode(p, se)
 	case "iq":
-		return &ClientIQ{}, nil
+		return iq.decode(p, se)
 	default:
 		return nil, errors.New("unexpected XMPP packet " +
 			se.Name.Space + " <" + se.Name.Local + "/>")
 	}
 }
 
-func decodeComponent(se xml.StartElement) (interface{}, error) {
+func decodeComponent(p *xml.Decoder, se xml.StartElement) (Packet, error) {
 	switch se.Name.Local {
 	case "handshake":
-		return &Handshake{}, nil
+		return handshake.decode(p, se)
 	case "iq":
-		return &ClientIQ{}, nil
+		return iq.decode(p, se)
 	default:
 		return nil, errors.New("unexpected XMPP packet " +
 			se.Name.Space + " <" + se.Name.Local + "/>")

presence.go

@@ -2,12 +2,28 @@ package xmpp // import "fluux.io/xmpp"
 
 import "encoding/xml"
 
-// XMPP Packet Parsing
-type ClientPresence struct {
-	XMLName xml.Name `xml:"jabber:client presence"`
+// ============================================================================
+// Presence Packet
+
+type Presence struct {
+	XMLName xml.Name `xml:"presence"`
 	PacketAttrs
 	Show     string `xml:"show,attr,omitempty"` // away, chat, dnd, xa
 	Status   string `xml:"status,attr,omitempty"`
 	Priority string `xml:"priority,attr,omitempty"`
 	//Error    *clientError
 }
+
+func (Presence) Name() string {
+	return "presence"
+}
+
+type presenceDecoder struct{}
+
+var presence presenceDecoder
+
+func (presenceDecoder) decode(p *xml.Decoder, se xml.StartElement) (Presence, error) {
+	var packet Presence
+	err := p.DecodeElement(&packet, &se)
+	return packet, err
+}

session.go

@@ -157,7 +157,7 @@ func (s *Session) bind(o Options) {
 		fmt.Fprintf(s.socketProxy, "<iq type='set' id='%s'><bind xmlns='%s'/></iq>", s.PacketId(), nsBind)
 	}
 
-	var iq ClientIQ
+	var iq IQ
 	if s.err = s.decoder.Decode(&iq); s.err != nil {
 		s.err = errors.New("error decoding iq bind result: " + s.err.Error())
 		return
@@ -180,7 +180,7 @@ func (s *Session) rfc3921Session(o Options) {
 		return
 	}
 
-	var iq ClientIQ
+	var iq IQ
 	if s.Features.Session.optional.Local != "" {
 		fmt.Fprintf(s.socketProxy, "<iq type='set' id='%s'><session xmlns='%s'/></iq>", s.PacketId(), nsSession)
 		if s.err = s.decoder.Decode(&iq); s.err != nil {

stream.go

@@ -1,8 +1,12 @@
 package xmpp // import "fluux.io/xmpp"
 
-import "encoding/xml"
+import (
+	"encoding/xml"
+)
+
+// ============================================================================
+// StreamFeatures Packet
 
-// XMPP PacketAttrs Parsing
 type streamFeatures struct {
 	XMLName    xml.Name `xml:"http://etherx.jabber.org/streams features"`
 	StartTLS   tlsStartTLS
@@ -13,11 +17,31 @@ type streamFeatures struct {
 	Any        []xml.Name `xml:",any"`
 }
 
+// ============================================================================
+// StreamError Packet
+
 type StreamError struct {
 	XMLName xml.Name `xml:"http://etherx.jabber.org/streams error"`
 	Error   xml.Name `xml:",any"`
 }
 
+func (StreamError) Name() string {
+	return "stream:error"
+}
+
+type streamErrorDecoder struct{}
+
+var streamError streamErrorDecoder
+
+func (streamErrorDecoder) decode(p *xml.Decoder, se xml.StartElement) (StreamError, error) {
+	var packet StreamError
+	err := p.DecodeElement(&packet, &se)
+	return packet, err
+}
+
+// ============================================================================
+// Caps subElement
+
 type Caps struct {
 	XMLName xml.Name `xml:"http://jabber.org/protocol/caps c"`
 	Hash    string   `xml:"hash,attr"`