Move examples out of the cmd directory

They are now in _examples dir.
Fix #26

_examples/xmpp_component/README.md

@@ -0,0 +1,20 @@
+# xmpp_component
+
+This component will connect to ejabberd and act as a subdomain "service" of your primary XMPP domain
+(in that case localhost).
+
+To be able to connect this component, you need to add a listener to your XMPP server.
+
+Here is an example ejabberd configuration for that component listener:
+
+```yaml
+listen:
+...
+  -
+    port: 8888
+    module: ejabberd_service
+    password: "mypass"
+```
+
+ejabberd will listen for a component (service) on port 8888 and allows it to connect using the
+secret "mypass".

_examples/xmpp_component/xmpp_component.go

@@ -0,0 +1,105 @@
+package main
+
+import (
+	"fmt"
+	"log"
+
+	"gosrc.io/xmpp"
+)
+
+func main() {
+	component := MyComponent{Name: "Test Component", Category: "gateway", Type: "service"}
+	component.xmpp = &xmpp.Component{Host: "service.localhost", Secret: "mypass"}
+	if err := component.xmpp.Connect("localhost:8888"); err != nil {
+		log.Fatal(err)
+	}
+
+	for {
+		packet, err := component.xmpp.ReadPacket()
+		if err != nil {
+			fmt.Println("read error", err)
+			return
+		}
+
+		switch p := packet.(type) {
+		case xmpp.IQ:
+			switch inner := p.Payload[0].(type) {
+			case *xmpp.DiscoInfo:
+				fmt.Println("Disco Info")
+				if p.Type == "get" {
+					DiscoResult(component, p.PacketAttrs, inner)
+				}
+			case *xmpp.DiscoItems:
+				fmt.Println("DiscoItems")
+				if p.Type == "get" {
+					DiscoItems(component, p.PacketAttrs, inner)
+				}
+			default:
+				fmt.Println("ignoring iq packet", inner)
+				xError := xmpp.Err{
+					Code:   501,
+					Reason: "feature-not-implemented",
+					Type:   "cancel",
+				}
+				reply := p.MakeError(xError)
+				_ = component.xmpp.Send(&reply)
+			}
+
+		case xmpp.Message:
+			fmt.Println("Received message:", p.Body)
+
+		case xmpp.Presence:
+			fmt.Println("Received presence:", p.Type)
+
+		default:
+			fmt.Println("ignoring packet:", packet)
+		}
+	}
+}
+
+type MyComponent struct {
+	Name string
+	// Typical categories and types: https://xmpp.org/registrar/disco-categories.html
+	Category string
+	Type     string
+
+	xmpp *xmpp.Component
+}
+
+func DiscoResult(c MyComponent, attrs xmpp.PacketAttrs, info *xmpp.DiscoInfo) {
+	iq := xmpp.NewIQ("result", attrs.To, attrs.From, attrs.Id, "en")
+	var identity xmpp.Identity
+	if info.Node == "" {
+		identity = xmpp.Identity{
+			Name:     c.Name,
+			Category: c.Category,
+			Type:     c.Type,
+		}
+	}
+
+	payload := xmpp.DiscoInfo{
+		Identity: identity,
+		Features: []xmpp.Feature{
+			{Var: xmpp.NSDiscoInfo},
+			{Var: xmpp.NSDiscoItems},
+		},
+	}
+	iq.AddPayload(&payload)
+
+	_ = c.xmpp.Send(iq)
+}
+
+func DiscoItems(c MyComponent, attrs xmpp.PacketAttrs, items *xmpp.DiscoItems) {
+	iq := xmpp.NewIQ("result", attrs.To, attrs.From, attrs.Id, "en")
+
+	var payload xmpp.DiscoItems
+	if items.Node == "" {
+		payload = xmpp.DiscoItems{
+			Items: []xmpp.DiscoItem{
+				{Name: "test node", JID: "service.localhost", Node: "node1"},
+			},
+		}
+	}
+	iq.AddPayload(&payload)
+	_ = c.xmpp.Send(iq)
+}