Implement a bit of XEP-0060 (PubSub) (#119)

This squashed series of commits implements basic
PubSub functionality like requesting data or
subscribing to a PubSub node.

xmpp.go

@@ -640,6 +640,11 @@ func (c *Client) Recv() (stanza interface{}, err error) {
 		}
 		switch v := val.(type) {
 		case *clientMessage:
+			if v.Event.XMLNS == XMPPNS_PUBSUB_EVENT {
+				// Handle Pubsub notifications
+				return pubsubClientToReturn(v.Event), nil
+			}
+
 			stamp, _ := time.Parse(
 				"2006-01-02T15:04:05Z",
 				v.Delay.Stamp,
@@ -664,19 +669,91 @@ func (c *Client) Recv() (stanza interface{}, err error) {
 		case *clientPresence:
 			return Presence{v.From, v.To, v.Type, v.Show, v.Status}, nil
 		case *clientIQ:
-			// TODO check more strictly
+			switch {
-			if v.Query.XMLName.Space == "urn:xmpp:ping" {
+			case v.Query.XMLName.Space == "urn:xmpp:ping":
+				// TODO check more strictly
 				err := c.SendResultPing(v.ID, v.From)
 				if err != nil {
 					return Chat{}, err
 				}
-			}
+				fallthrough
-			if v.Query.XMLName.Local == "" {
+			case v.Type == "error":
+				switch v.ID {
+				case "sub1":
+					// Pubsub subscription failed
+					var errs []clientPubsubError
+					err := xml.Unmarshal([]byte(v.Error.InnerXML), &errs)
+					if err != nil {
+						return PubsubSubscription{}, err
+					}
+
+					var errsStr []string
+					for _, e := range errs {
+						errsStr = append(errsStr, e.XMLName.Local)
+					}
+
+					return PubsubSubscription{
+						Errors: errsStr,
+					}, nil
+				}
+			case v.Type == "result" && v.ID == "unsub1":
+				// Unsubscribing MAY contain a pubsub element. But it does
+				// not have to
+				return PubsubUnsubscription{
+					SubID:  "",
+					JID:    v.From,
+					Node:   "",
+					Errors: nil,
+				}, nil
+			case v.Query.XMLName.Local == "pubsub":
+				switch v.ID {
+				case "sub1":
+					// Subscription or unsubscription was successful
+					var sub clientPubsubSubscription
+					err := xml.Unmarshal([]byte(v.Query.InnerXML), &sub)
+					if err != nil {
+						return PubsubSubscription{}, err
+					}
+
+					return PubsubSubscription{
+						SubID:  sub.SubID,
+						JID:    sub.JID,
+						Node:   sub.Node,
+						Errors: nil,
+					}, nil
+				case "unsub1":
+					var sub clientPubsubSubscription
+					err := xml.Unmarshal([]byte(v.Query.InnerXML), &sub)
+					if err != nil {
+						return PubsubUnsubscription{}, err
+					}
+
+					return PubsubUnsubscription{
+						SubID:  sub.SubID,
+						JID:    v.From,
+						Node:   sub.Node,
+						Errors: nil,
+					}, nil
+				case "items1", "items3":
+					var p clientPubsubItems
+					err := xml.Unmarshal([]byte(v.Query.InnerXML), &p)
+					if err != nil {
+						return PubsubItems{}, err
+					}
+
+					return PubsubItems{
+						p.Node,
+						pubsubItemsToReturn(p.Items),
+					}, nil
+				}
+			case v.Query.XMLName.Local == "":
 				return IQ{ID: v.ID, From: v.From, To: v.To, Type: v.Type}, nil
-			} else if res, err := xml.Marshal(v.Query); err != nil {
+			default:
-				// should never occur
+				res, err := xml.Marshal(v.Query)
-				return Chat{}, err
+				if err != nil {
-			} else {
+					return Chat{}, err
+				}
+
 				return IQ{ID: v.ID, From: v.From, To: v.To, Type: v.Type,
 					Query: res}, nil
 			}
@@ -832,6 +909,9 @@ type clientMessage struct {
 	Body    string `xml:"body"`
 	Thread  string `xml:"thread"`
 
+	// Pubsub
+	Event clientPubsubEvent `xml:"event"`
+
 	// Any hasn't matched element
 	Other []XMLElement `xml:",any"`
 
@@ -909,11 +989,12 @@ type clientIQ struct {
 }
 
 type clientError struct {
-	XMLName xml.Name `xml:"jabber:client error"`
+	XMLName  xml.Name `xml:"jabber:client error"`
-	Code    string   `xml:",attr"`
+	Code     string   `xml:",attr"`
-	Type    string   `xml:",attr"`
+	Type     string   `xml:"type,attr"`
-	Any     xml.Name
+	Any      xml.Name
-	Text    string
+	InnerXML []byte `xml:",innerxml"`
+	Text     string
 }
 
 type clientQuery struct {

xmpp_pubsub.go

@@ -0,0 +1,133 @@
+package xmpp
+
+import (
+	"encoding/xml"
+	"fmt"
+)
+
+const (
+	XMPPNS_PUBSUB       = "http://jabber.org/protocol/pubsub"
+	XMPPNS_PUBSUB_EVENT = "http://jabber.org/protocol/pubsub#event"
+)
+
+type clientPubsubItem struct {
+	XMLName xml.Name `xml:"item"`
+	ID      string   `xml:"id,attr"`
+	Body    []byte   `xml:",innerxml"`
+}
+
+type clientPubsubItems struct {
+	XMLName xml.Name           `xml:"items"`
+	Node    string             `xml:"node,attr"`
+	Items   []clientPubsubItem `xml:"item"`
+}
+
+type clientPubsub struct {
+	XMLName xml.Name          `xml:"pubsub"`
+	Items   clientPubsubItems `xml:"items"`
+}
+
+type clientPubsubEvent struct {
+	XMLName xml.Name          `xml:"event"`
+	XMLNS   string            `xml:"xmlns,attr"`
+	Items   clientPubsubItems `xml:"items"`
+}
+
+type clientPubsubError struct {
+	XMLName xml.Name
+}
+
+type clientPubsubSubscription struct {
+	XMLName xml.Name `xml:"subscription"`
+	Node    string   `xml:"node,attr"`
+	JID     string   `xml:"jid,attr"`
+	SubID   string   `xml:"subid,attr"`
+}
+
+type PubsubEvent struct {
+	Node  string
+	Items []PubsubItem
+}
+
+type PubsubSubscription struct {
+	SubID  string
+	JID    string
+	Node   string
+	Errors []string
+}
+type PubsubUnsubscription PubsubSubscription
+
+type PubsubItem struct {
+	ID       string
+	InnerXML []byte
+}
+
+type PubsubItems struct {
+	Node  string
+	Items []PubsubItem
+}
+
+// Converts []clientPubsubItem to []PubsubItem
+func pubsubItemsToReturn(items []clientPubsubItem) []PubsubItem {
+	var tmp []PubsubItem
+	for _, i := range items {
+		tmp = append(tmp, PubsubItem{
+			ID:       i.ID,
+			InnerXML: i.Body,
+		})
+	}
+
+	return tmp
+}
+
+func pubsubClientToReturn(event clientPubsubEvent) PubsubEvent {
+	return PubsubEvent{
+		Node:  event.Items.Node,
+		Items: pubsubItemsToReturn(event.Items.Items),
+	}
+}
+
+func pubsubStanza(body string) string {
+	return fmt.Sprintf("<pubsub xmlns='%s'>%s</pubsub>",
+		XMPPNS_PUBSUB, body)
+}
+
+func pubsubSubscriptionStanza(node, jid string) string {
+	body := fmt.Sprintf("<subscribe node='%s' jid='%s'/>",
+		xmlEscape(node),
+		xmlEscape(jid))
+	return pubsubStanza(body)
+}
+
+func pubsubUnsubscriptionStanza(node, jid string) string {
+	body := fmt.Sprintf("<unsubscribe node='%s' jid='%s'/>",
+		xmlEscape(node),
+		xmlEscape(jid))
+	return pubsubStanza(body)
+}
+
+func (c *Client) PubsubSubscribeNode(node, jid string) {
+	c.RawInformation(c.jid,
+		jid,
+		"sub1",
+		"set",
+		pubsubSubscriptionStanza(node, c.jid))
+}
+
+func (c *Client) PubsubUnsubscribeNode(node, jid string) {
+	c.RawInformation(c.jid,
+		jid,
+		"unsub1",
+		"set",
+		pubsubUnsubscriptionStanza(node, c.jid))
+}
+
+func (c *Client) PubsubRequestLastItems(node, jid string) {
+	body := fmt.Sprintf("<items node='%s'/>", node)
+	c.RawInformation(c.jid, jid, "items1", "get", pubsubStanza(body))
+}
+
+func (c *Client) PubsubRequestItem(node, jid, id string) {
+	body := fmt.Sprintf("<items node='%s'><item id='%s'/></items>", node, id)
+	c.RawInformation(c.jid, jid, "items3", "get", pubsubStanza(body))
+}