Added arn to the main repository

arn/Likeable.go

@@ -0,0 +1,78 @@
+package arn
+
+import (
+	"errors"
+	"reflect"
+
+	"github.com/aerogo/aero"
+	"github.com/aerogo/api"
+)
+
+// Likeable ...
+type Likeable interface {
+	Like(userID UserID)
+	Unlike(userID UserID)
+	LikedBy(userID UserID) bool
+	CountLikes() int
+	Link() string
+	Save()
+}
+
+// LikeEventReceiver ...
+type LikeEventReceiver interface {
+	OnLike(user *User)
+}
+
+// LikeAction ...
+func LikeAction() *api.Action {
+	return &api.Action{
+		Name:  "like",
+		Route: "/like",
+		Run: func(obj interface{}, ctx aero.Context) error {
+			field := reflect.ValueOf(obj).Elem().FieldByName("IsDraft")
+
+			if field.IsValid() && field.Bool() {
+				return errors.New("Drafts need to be published before they can be liked")
+			}
+
+			likeable := obj.(Likeable)
+			user := GetUserFromContext(ctx)
+
+			if user == nil {
+				return errors.New("Not logged in")
+			}
+
+			likeable.Like(user.ID)
+
+			// Call OnLike if the object implements it
+			receiver, ok := likeable.(LikeEventReceiver)
+
+			if ok {
+				receiver.OnLike(user)
+			}
+
+			likeable.Save()
+			return nil
+		},
+	}
+}
+
+// UnlikeAction ...
+func UnlikeAction() *api.Action {
+	return &api.Action{
+		Name:  "unlike",
+		Route: "/unlike",
+		Run: func(obj interface{}, ctx aero.Context) error {
+			likeable := obj.(Likeable)
+			user := GetUserFromContext(ctx)
+
+			if user == nil {
+				return errors.New("Not logged in")
+			}
+
+			likeable.Unlike(user.ID)
+			likeable.Save()
+			return nil
+		},
+	}
+}