feat(server): implement miner ranking api

app/controllers/api/v1/statistics_controller.rb

@@ -5,6 +5,11 @@ def index
         statistic_info = StatisticInfo.new
         render json: IndexStatisticSerializer.new(statistic_info)
       end
+
+      def show
+        ranking = MinerRanking.new
+        render json: MinerRankingSerializer.new(ranking)
+      end
     end
   end
 end

app/serializers/miner_ranking_serializer.rb

@@ -0,0 +1,4 @@
+class MinerRankingSerializer
+  include FastJsonapi::ObjectSerializer
+  attributes :ranking
+end

config/routes.rb

@@ -20,7 +20,7 @@
       resources :cell_output_type_scripts, only: :show
       resources :cell_output_data, only: :show
       resources :suggest_queries, only: :index
-      resources :statistics, only: :index
+      resources :statistics, only: %i(index show)
     end
   end
 end