Add profile retrieving

cmd/bot/main.go

@@ -23,23 +23,28 @@ func main() {
 
 	conf.Parse()
 
-	m := messenger.New(messenger.Options{
+	client := messenger.New(messenger.Options{
 		Verify:      *verify,
 		VerifyToken: *verifyToken,
 		Token:       *pageToken,
 	})
 
-	m.HandleMessage(func(m messenger.Message, r *messenger.Response) {
+	client.HandleMessage(func(m messenger.Message, r *messenger.Response) {
 		fmt.Printf("%v (Sent, %v)\n", m.Text, m.Time.Format(time.UnixDate))
-		fmt.Println(r.Text("Hello, World!"))
-		fmt.Println(m.Attachments)
+
+		p, err := client.ProfileByID(m.Sender.ID)
+		if err != nil {
+			fmt.Println("Something went wrong!", err)
+		}
+
+		r.Text(fmt.Sprintf("Hello, %v!", p.FirstName))
 	})
 
-	m.HandleDelivery(func(d messenger.Delivery, r *messenger.Response) {
+	client.HandleDelivery(func(d messenger.Delivery, r *messenger.Response) {
 		fmt.Println(d.Watermark().Format(time.UnixDate))
 	})
 
 	fmt.Println("Serving messenger bot on localhost:8080")
 
-	http.ListenAndServe("localhost:8080", m.Handler())
+	http.ListenAndServe("localhost:8080", client.Handler())
 }

messenger.go

@@ -10,6 +10,10 @@ import (
 const (
 	// WebhookURL is where the Messenger client should listen for webhook events.
 	WebhookURL = "/webhook"
+
+	// ProfileURL is the API endpoint used for retrieving profiles.
+	// Used in the form: https://graph.facebook.com/v2.6/<USER_ID>?fields=first_name,last_name,profile_pic&access_token=<PAGE_ACCESS_TOKEN>
+	ProfileURL = "https://graph.facebook.com/v2.6/"
 )
 
 // Options are the settings used when creating a Messenger client.
@@ -71,6 +75,27 @@ func (m *Messenger) Handler() http.Handler {
 	return m.mux
 }
 
+// ProfileByID retrieves the Facebook user associated with that ID
+func (m *Messenger) ProfileByID(id int64) (Profile, error) {
+	p := Profile{}
+	url := fmt.Sprintf("%v%v", ProfileURL, id)
+
+	req, err := http.NewRequest("GET", url, nil)
+	if err != nil {
+		return p, err
+	}
+
+	req.URL.RawQuery = "fields=first_name,last_name,profile_pic&access_token=" + m.token
+
+	client := &http.Client{}
+	resp, err := client.Do(req)
+	defer resp.Body.Close()
+
+	err = json.NewDecoder(resp.Body).Decode(&p)
+
+	return p, err
+}
+
 // handle is the internal HTTP handler for the webhooks.
 func (m *Messenger) handle(w http.ResponseWriter, r *http.Request) {
 	var rec Receive

profile.go

@@ -0,0 +1,8 @@
+package messenger
+
+// Profile is the public information of a Facebook user
+type Profile struct {
+	FirstName     string `json:"first_name"`
+	LastName      string `json:"last_name"`
+	ProfilePicURL string `json:"profile_pic"`
+}