Initial commit

app/models/common_data/singleton.rb

@@ -0,0 +1,25 @@
+class CommonDataSingleton
+  include Singleton
+
+  def initialize
+    @common_data = nil
+    @last_usage = Time.now
+  end
+
+  def datasets(visualizations_api_url)
+    now = Time.now
+    if @common_data.nil? || (now - @last_usage > (cache_ttl * 60))
+      @common_data = CommonData.new(visualizations_api_url)
+      @last_usage = now
+    end
+    @common_data.datasets
+  end
+
+  def cache_ttl
+    ttl = 0
+    if Cartodb.config[:common_data].present?
+      ttl = Cartodb.config[:common_data]['cache_ttl'] || ttl
+    end
+    ttl
+  end
+end