Add post action creator

lib/post_action_creator.rb

@@ -0,0 +1,20 @@
+# creates post actions based on a post and a user
+class PostActionCreator
+
+  def initialize(user, post)
+    @user = user
+    @post = post
+  end
+
+  def perform(action)
+    guardian.ensure_post_can_act!(@post, action, taken_actions: PostAction.counts_for([@post], @user)[@post.id])
+    PostAction.act(@user, @post, action)
+  end
+
+  private
+
+  def guardian
+    @guardian ||= Guardian.new(@user)
+  end
+
+end