Add filtering on state

app/controllers/api/v1/parks_controller.rb

@@ -2,10 +2,11 @@ class Api::V1::ParksController < ApplicationController
   DEFAULT_PAGE_SIZE = 10
 
   def index
-    parks = Park
+    parks = Park.all
-      .limit(per_page)
+    if params[:state].present?
-      .offset((page - 1) * per_page)
+      parks = parks.where("states like '%' || ? || '%'", params[:state])
-    render json: parks
+    end
+    render json: parks.limit(per_page).offset((page - 1) * per_page)
   end
 
   private