xmpp.go
changeset 0 6dbd969c8f3a
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/xmpp.go	Fri Dec 23 22:44:51 2011 -0700
@@ -0,0 +1,113 @@
+// Copyright 2011 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This package implements a simple XMPP client according to RFCs 3920
+// and 3921, plus the various XEPs at http://xmpp.org/protocols/.
+package xmpp
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"os"
+	"xml"
+)
+
+const (
+	// Version of RFC 3920 that we implement.
+	Version = "1.0"
+	nsStreams = "urn:ietf:params:xml:ns:xmpp-streams"
+)
+
+// JID represents an entity that can communicate with other
+// entities. It looks like node@domain/resource. Node and resource are
+// sometimes optional.
+type JID struct {
+	Node *string
+	Domain string
+	Resource *string
+}
+var _ fmt.Stringer = &JID{}
+
+// XMPP's <stream:stream> XML element
+type Stream struct {
+	to string `xml:"attr"`
+	from string `xml:"attr"`
+	id string `xml:"attr"`
+	lang string `xml:"attr"`
+	version string `xml:"attr"`
+}
+var _ xml.Marshaler = &Stream{}
+
+type StreamError struct {
+	cond definedCondition
+	text errText
+}
+var _ xml.Marshaler = &StreamError{}
+
+type definedCondition struct {
+	// Must always be in namespace nsStreams
+	XMLName xml.Name
+}
+
+type errText struct {
+	XMLName xml.Name
+	Lang string
+	text string `xml:"chardata"`
+}
+var _ xml.Marshaler = &errText{}
+
+func (jid *JID) String() string {
+	result := jid.Domain
+	if jid.Node != nil {
+		result = *jid.Node + "@" + result
+	}
+	if jid.Resource != nil {
+		result = result + "/" + *jid.Resource
+	}
+	return result
+}
+
+func (s *Stream) MarshalXML() ([]byte, os.Error) {
+	buf := bytes.NewBuffer(nil)
+	buf.WriteString("<stream:stream")
+	writeField(buf, "to", s.to)
+	writeField(buf, "from", s.from)
+	writeField(buf, "id", s.id)
+	writeField(buf, "xml:lang", s.lang)
+	writeField(buf, "version", s.version)
+	buf.WriteString(">")
+	// We never write </stream:stream>
+	return buf.Bytes(), nil
+}
+
+func (s *StreamError) MarshalXML() ([]byte, os.Error) {
+	buf := bytes.NewBuffer(nil)
+	buf.WriteString("<stream:error>")
+	xml.Marshal(buf, s.cond)
+	xml.Marshal(buf, s.text)
+	buf.WriteString("</stream:error>")
+	return buf.Bytes(), nil
+}
+
+func (e *errText) MarshalXML() ([]byte, os.Error) {
+	buf := bytes.NewBuffer(nil)
+	buf.WriteString("<text")
+	writeField(buf, "xmlns", nsStreams)
+	writeField(buf, "xml:lang", e.Lang)
+	buf.WriteString(">")
+	xml.Escape(buf, []byte(e.text))
+	buf.WriteString("</text>")
+	return buf.Bytes(), nil
+}
+
+func writeField(w io.Writer, field, value string) {
+	if value != "" {
+		io.WriteString(w, " ")
+		io.WriteString(w, field)
+		io.WriteString(w, `="`)
+		xml.Escape(w, []byte(value))
+		io.WriteString(w, `"`)
+	}
+}