First working version of new RX concept

This uses xml.Decoder.DecodeElement() which makes parsing way easier.

This first step is just able to parse stream features partially.

4 files changed, 31 insertions, 48 deletions

diff --git a/xmpp/router.go b/xmpp/router.go
index 1e21c9b..d437b28 100644
--- a/xmpp/router.go
+++ b/xmpp/router.go
@@ -2,7 +2,6 @@ package xmpp
 
 import (
 	"encoding/xml"
-	"log"
 )
 
 // routingTable is a data structure which contains routing information for XML
@@ -12,7 +11,7 @@ import (
 // entry of the routingTable.
 type routingTable []struct {
 	name    xml.Name
-	handler func(*session, []xml.Token)
+	handler func(s *xml.StartElement, d *xml.Decoder, c chan<- any)
 }
 
 // getRoutingTable returns the routing table used in
@@ -23,40 +22,19 @@ type routingTable []struct {
 func getRoutingTable() routingTable {
 	return routingTable{
 		{xml.Name{`http://etherx.jabber.org/streams`, `features`}, streamFeaturesHandler},
-		{xml.Name{`urn:ietf:params:xml:ns:xmpp-sasl`, `success`}, saslSuccessHandler},
-		{xml.Name{`urn:ietf:params:xml:ns:xmpp-sasl`, `failure`}, saslFailureHandler},
-		{xml.Name{`jabber:client`, `iq`}, iqHandler},
+//		{xml.Name{`urn:ietf:params:xml:ns:xmpp-sasl`, `success`}, saslSuccessHandler},
+//		{xml.Name{`urn:ietf:params:xml:ns:xmpp-sasl`, `failure`}, saslFailureHandler},
+//		{xml.Name{`jabber:client`, `iq`}, iqHandler},
 	}
 }
 
 // route determines the correct handler function for the given XML element by a
 // given routingTable. In addition it executes the determined handler function.
 // If no handler function is found an error message is send via the log module.
-func route(s *session, e []xml.Token, t routingTable) {
-	var name xml.Name
-
-	// TODO a stronger definition of an XML element (as here
-	// https://www.w3schools.com/xml/xml_elements.asp) would define that the
-	// first Token of an element is a StartElement token. This would make this
-	// code easier.
-	escape := false
-	for _, token := range e {
-		switch s := token.(type) {
-		case xml.StartElement:
-			name = s.Name
-			escape = true
-		}
-		if escape {
-			break
-		}
-	}
-
-	for _, r := range t {
-		if name == r.name {
-			r.handler(s, e)
-			return
+func route(s *xml.StartElement, d *xml.Decoder, c chan<- any, t routingTable) {
+	for _, v := range t {
+		if v.name == (*s).Name {
+			v.handler(s, d, c)
 		}
 	}
-
-	log.Println("Could not route XML element")
 }
diff --git a/xmpp/session.go b/xmpp/session.go
index 4be3386..6abc343 100644
--- a/xmpp/session.go
+++ b/xmpp/session.go
@@ -20,7 +20,7 @@ type session struct {
 	out         chan<- any
 	transport   *tls.Conn
 	tx          *xml.Encoder
-	rx          chan xml.Token
+	rx          chan any
 	resourceReq string
 }
 
@@ -31,7 +31,7 @@ func StartSession(out chan<- any, jid string, pwd string) (in chan<- any) {
 	s.pwd = pwd
 	s.in = make(chan any)
 	s.out = out
-	s.rx = make(chan xml.Token, 0)
+	s.rx = make(chan any, 0)
 
 	go s.run()
 
diff --git a/xmpp/streams.go b/xmpp/streams.go
index b9c0cb7..9c90554 100644
--- a/xmpp/streams.go
+++ b/xmpp/streams.go
@@ -40,20 +40,6 @@ func closeStream(e *xml.Encoder) {
 	}
 }
 
-func streamFeaturesHandler(s *session, e []xml.Token) {
-	if hasSaslPlain(e) {
-		s.sasl()
-		return
-	}
-
-	if hasBind(e) {
-		s.sendBind()
-		return
-	}
-
-	log.Println("Stream has no implemented features!")
-}
-
 func iqHandler(s *session, e []xml.Token) {
 	isResult := false
 	idMatches := false
@@ -77,3 +63,22 @@ func iqHandler(s *session, e []xml.Token) {
 		}
 	}
 }
+
+type streamFeatures struct {
+	Mechanisms struct {
+		Items []struct {
+			Type string `xml:",innerxml"`
+		} `xml:"mechanism"`
+	} `xml:"mechanisms"`
+}
+
+func streamFeaturesHandler(s *xml.StartElement, d *xml.Decoder, c chan<- any) {
+	e := streamFeatures{}
+
+	err := d.DecodeElement(&e, s)
+	if err != nil {
+		log.Printf("Could not decode stream features: %v\n", err)
+	}
+
+	c <- e
+}
diff --git a/xmpp/xml.go b/xmpp/xml.go
index 36d7eb1..470a2ef 100644
--- a/xmpp/xml.go
+++ b/xmpp/xml.go
@@ -9,7 +9,7 @@ import (
 	"log"
 )
 
-func runRx(ctx context.Context, chn chan xml.Token, conn *tls.Conn) {
+func runRx(ctx context.Context, chn chan<- any, conn *tls.Conn) {
 
 	l := logger{"[RX] "}
 	r := io.TeeReader(conn, l)
@@ -27,7 +27,7 @@ func runRx(ctx context.Context, chn chan xml.Token, conn *tls.Conn) {
 					if e.Name.Local == "stream" {
 						// new server-side stream TODO what to do with this info?
 					} else {
-//						route(&e, &d, chn, getRoutingTable())
+						route(&e, d, chn, getRoutingTable())
 					}
 				case xml.EndElement:
 					if e.Name.Local == "stream" {