Add schema and metadata information to the definition file

Since the definition file is often used in third party applications, I
need a way to reference changes to the schema itself directly in the
file.

I adopted the approach where the will be always a _ element in the file
containing metadata, such as the schema version.

Consumers should always check if (and compare the version) before
processing the definition list.

.simplecov

@@ -1,3 +1,4 @@
 SimpleCov.start do
   add_filter "/spec/"
-end
+  add_filter "/utils/"
+end

lib/whois/server.rb

@@ -61,6 +61,7 @@ def self.load_definitions
     def self.load_json(file)
       type = File.basename(file, File.extname(file)).to_sym
       JSON.load(File.read(file)).each do |allocation, settings|
+        next if allocation == "_"
         define(type, allocation, settings.delete("host"), Hash[settings.map { |k,v| [k.to_sym, v] }])
       end
     end

utils/deftld.rb

@@ -5,6 +5,14 @@
 require 'json'
 
 class TldDefs
+
+  KEY_SCHEMA = "_".freeze
+
+  # The current schema version for the definition file
+  #
+  # @return [String] version
+  SCHEMA_VERSION = "2".freeze
+
   class TldDef
     attr_accessor :name
 
@@ -86,6 +94,7 @@ def read
   end
 
   def write(data)
+    data[KEY_SCHEMA] = schema_attributes
     data = Hash[data.sort_by { |tld, _| tld.split(".").reverse.join(".") }]
     JSON.pretty_generate(data)
   end
@@ -128,6 +137,16 @@ def validate
       TldDef.new(tld, data)
     end; nil
   end
+
+  private
+
+  def schema_attributes
+    {
+        "schema" => SCHEMA_VERSION,
+        "updated" => Time.now.utc,
+    }
+  end
+
 end
 
 args = ARGV