PubSub protocol support (#142)

* PubSub protocol support
Added support for :
- XEP-0050   (Command))
- XEP-0060   (PubSub)
- XEP-0004   (Forms)

Fixed the NewClient function by adding parsing of the domain from the JID if no domain is provided in transport config.
Updated xmpp_jukebox example

* Delete useless pubsub errors

* README.md update
Fixed import in echo example

* Typo

* Fixed raw send on client example

* Fixed jukebox example and added a README.md

stanza/jid_test.go

@@ -0,0 +1,86 @@
+package stanza
+
+import (
+	"testing"
+)
+
+func TestValidJids(t *testing.T) {
+	tests := []struct {
+		jidstr   string
+		expected Jid
+	}{
+		{jidstr: "test@domain.com", expected: Jid{"test", "domain.com", ""}},
+		{jidstr: "test@domain.com/resource", expected: Jid{"test", "domain.com", "resource"}},
+		// resource can contain '/' or '@'
+		{jidstr: "test@domain.com/a/b", expected: Jid{"test", "domain.com", "a/b"}},
+		{jidstr: "test@domain.com/a@b", expected: Jid{"test", "domain.com", "a@b"}},
+		{jidstr: "domain.com", expected: Jid{"", "domain.com", ""}},
+	}
+
+	for _, tt := range tests {
+		jid, err := NewJid(tt.jidstr)
+		if err != nil {
+			t.Errorf("could not parse correct jid: %s", tt.jidstr)
+			continue
+		}
+
+		if jid == nil {
+			t.Error("jid should not be nil")
+		}
+
+		if jid.Node != tt.expected.Node {
+			t.Errorf("incorrect jid Node (%s): %s", tt.expected.Node, jid.Node)
+		}
+
+		if jid.Node != tt.expected.Node {
+			t.Errorf("incorrect jid domain (%s): %s", tt.expected.Domain, jid.Domain)
+		}
+
+		if jid.Resource != tt.expected.Resource {
+			t.Errorf("incorrect jid resource (%s): %s", tt.expected.Resource, jid.Resource)
+		}
+	}
+}
+
+func TestIncorrectJids(t *testing.T) {
+	badJids := []string{
+		"",
+		"user@",
+		"@domain.com",
+		"user:name@domain.com",
+		"user<name@domain.com",
+		"test@domain.com@otherdomain.com",
+		"test@domain com/resource",
+	}
+
+	for _, sjid := range badJids {
+		if _, err := NewJid(sjid); err == nil {
+			t.Error("parsing incorrect jid should return error: " + sjid)
+		}
+	}
+}
+
+func TestFull(t *testing.T) {
+	jid := "test@domain.com/my resource"
+	parsedJid, err := NewJid(jid)
+	if err != nil {
+		t.Errorf("could not parse jid: %v", err)
+	}
+	fullJid := parsedJid.Full()
+	if fullJid != jid {
+		t.Errorf("incorrect full jid: %s", fullJid)
+	}
+}
+
+func TestBare(t *testing.T) {
+	jid := "test@domain.com"
+	fullJid := jid + "/my resource"
+	parsedJid, err := NewJid(fullJid)
+	if err != nil {
+		t.Errorf("could not parse jid: %v", err)
+	}
+	bareJid := parsedJid.Bare()
+	if bareJid != jid {
+		t.Errorf("incorrect bare jid: %s", bareJid)
+	}
+}