Quick prototype of message extension

This is a work-in-progress, needs refactor.
5 years ago · b05efea81d
parent f74f276a22
commit b05efea81d
2 changed files with 160 additions and 4 deletions
--- a/message.go
+++ b/message.go
@ -3,6 +3,7 @@ package xmpp // import "gosrc.io/xmpp"
 import (
 	"encoding/xml"
 	"fmt"
+	"reflect"
 )

 // ============================================================================
@ -11,10 +12,11 @@ import (
 type Message struct {
 	XMLName xml.Name `xml:"message"`
 	PacketAttrs
-	Subject string `xml:"subject,omitempty"`
-	Body    string `xml:"body,omitempty"`
-	Thread  string `xml:"thread,omitempty"`
-	Error   Err    `xml:"error,omitempty"`
+	Subject    string         `xml:"subject,omitempty"`
+	Body       string         `xml:"body,omitempty"`
+	Thread     string         `xml:"thread,omitempty"`
+	Error      Err            `xml:"error,omitempty"`
+	Extensions []MsgExtension `xml:",omitempty"`
 }

 func (Message) Name() string {
@ -44,9 +46,109 @@ func (messageDecoder) decode(p *xml.Decoder, se xml.StartElement) (Message, erro
 	return packet, err
 }

+// TODO: Support missing element (thread, extensions) by using proper marshaller
 func (msg *Message) XMPPFormat() string {
 	return fmt.Sprintf("<message to='%s' type='chat' xml:lang='en'>"+
 		"<body>%s</body></message>",
 		msg.To,
 		xmlEscape(msg.Body))
 }
+
+// UnmarshalXML implements custom parsing for IQs
+func (msg *Message) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error {
+	msg.XMLName = start.Name
+
+	// Extract packet attributes
+	for _, attr := range start.Attr {
+		if attr.Name.Local == "id" {
+			msg.Id = attr.Value
+		}
+		if attr.Name.Local == "type" {
+			msg.Type = attr.Value
+		}
+		if attr.Name.Local == "to" {
+			msg.To = attr.Value
+		}
+		if attr.Name.Local == "from" {
+			msg.From = attr.Value
+		}
+		if attr.Name.Local == "lang" {
+			msg.Lang = attr.Value
+		}
+	}
+
+	// decode inner elements
+	for {
+		t, err := d.Token()
+		if err != nil {
+			return err
+		}
+
+		switch tt := t.(type) {
+
+		case xml.StartElement:
+			var elt interface{}
+			elementType := tt.Name.Space
+
+			if extensionType := msgTypeRegistry[elementType]; extensionType != nil {
+				val := reflect.New(extensionType)
+				elt = val.Interface()
+				if msgExt, ok := elt.(MsgExtension); ok {
+					err = d.DecodeElement(elt, &tt)
+					if err != nil {
+						return err
+					}
+					msg.Extensions = append(msg.Extensions, msgExt)
+				}
+			} else {
+				// Decode default message elements
+				var err error
+				switch tt.Name.Local {
+				case "body":
+					err = d.DecodeElement(&msg.Body, &tt)
+				case "thread":
+					err = d.DecodeElement(&msg.Thread, &tt)
+				case "subject":
+					err = d.DecodeElement(&msg.Subject, &tt)
+				case "error":
+					err = d.DecodeElement(&msg.Error, &tt)
+				}
+				if err != nil {
+					return err
+				}
+			}
+
+		case xml.EndElement:
+			if tt == start.End() {
+				return nil
+			}
+		}
+	}
+}
+
+// ============================================================================
+// Message extensions
+// Provide ability to add support to XMPP extension tags on messages
+
+type MsgExtension interface {
+	IsMsgExtension()
+}
+
+// XEP-0184
+type Receipt struct {
+	// xmlns: urn:xmpp:receipts
+	XMLName xml.Name
+	Id      string
+}
+
+func (*Receipt) IsMsgExtension() {}
+
+// ============================================================================
+// TODO: Make it configurable at to be able to easily add new XMPP extensions
+//    in separate modules
+
+var msgTypeRegistry = make(map[string]reflect.Type)
+
+func init() {
+	msgTypeRegistry["urn:xmpp:receipts"] = reflect.TypeOf(Receipt{})
+}
--- a/message_test.go
+++ b/message_test.go
@ -27,3 +27,57 @@ func TestGenerateMessage(t *testing.T) {
 		t.Errorf("non matching items\n%s", cmp.Diff(parsedMessage, message))
 	}
 }
+
+func TestDecodeError(t *testing.T) {
+	str := `<message from='juliet@capulet.com'
+         id='msg_1'
+         to='romeo@montague.lit'
+         type='error'>
+  <error type='cancel'>
+    <not-acceptable xmlns='urn:ietf:params:xml:ns:xmpp-stanzas'/>
+  </error>
+</message>`
+
+	parsedMessage := xmpp.Message{}
+	if err := xml.Unmarshal([]byte(str), &parsedMessage); err != nil {
+		t.Errorf("message error stanza unmarshall error: %v", err)
+		return
+	}
+	if parsedMessage.Error.Type != "cancel" {
+		t.Errorf("incorrect error type: %s", parsedMessage.Error.Type)
+	}
+}
+
+func TestDecodeXEP0184(t *testing.T) {
+	str := `<message
+    from='northumberland@shakespeare.lit/westminster'
+    id='richard2-4.1.247'
+    to='kingrichard@royalty.england.lit/throne'>
+  <body>My lord, dispatch; read o'er these articles.</body>
+  <request xmlns='urn:xmpp:receipts'/>
+</message>`
+	parsedMessage := xmpp.Message{}
+	if err := xml.Unmarshal([]byte(str), &parsedMessage); err != nil {
+		t.Errorf("message receipt unmarshall error: %v", err)
+		return
+	}
+
+	if parsedMessage.Body != "My lord, dispatch; read o'er these articles." {
+		t.Errorf("Unexpected body: '%s'", parsedMessage.Body)
+	}
+
+	if len(parsedMessage.Extensions) < 1 {
+		t.Errorf("no extension found on parsed message")
+		return
+	}
+
+	switch ext := parsedMessage.Extensions[0].(type) {
+	case *xmpp.Receipt:
+		if ext.XMLName.Local != "request" {
+			t.Errorf("unexpected extension: %s:%s", ext.XMLName.Space, ext.XMLName.Local)
+		}
+	default:
+		t.Errorf("could not find receipt extension")
+	}
+
+}