paging done, needs some additional refactoring

front-api/controllers/common_for_controllers.rb

@@ -3,6 +3,10 @@ def get_querystring_hash()
    Rack::Utils.parse_nested_query(request.query_string)
 end
 
+def add_total_count_header(total)
+  response.headers['X-Total-Count'] = total
+end
+
 # converts list of parameters to array of integers
 def mass_to_i(*id_strings)
   id_strings.map(&:to_i)

front-api/controllers/item.rb

@@ -21,7 +21,7 @@ end
 
 def filter_by_traits(items)
   get_querystring_hash.each do |k,v|
-    items = items.where(["traits ->> '#{k}' = '#{v}'"])
+    items = items.where(["traits ->> ? = ?", k, v])
   end
   items
 end
@@ -54,9 +54,12 @@ get '/item/category/:category_id/offset/:offset/limit/:limit' do |category_id_s,
   input_invalid = offset_and_limit_invalid?(offset,limit) or category_id <= 0
   return [].to_json if input_invalid 
 
+  all_in_cat = filter_by_traits(Item.all_in_category(category_id))
   items = Item.best_selling_in_category(category_id, offset,limit)
   items = filter_by_traits(items)
 
+  add_total_count_header(all_in_cat.count)
+
   prepare_items_for_mass_display(items)
 end