Add include_keys filter

lib/lit.rb

@@ -10,6 +10,7 @@ module Lit
   mattr_accessor :humanize_key
   mattr_accessor :humanize_key_ignored_keys
   mattr_accessor :humanize_key_ignored
+  mattr_accessor :included_keys
   mattr_accessor :ignored_keys
   mattr_accessor :ignore_yaml_on_startup
   mattr_accessor :api_enabled
@@ -31,6 +32,13 @@ def self.init
       Lit.humanize_key_ignored = %w[i18n date datetime number time support ]
       Lit.humanize_key_ignored |= Lit.humanize_key_ignored_keys
       Lit.humanize_key_ignored = %r{(#{Lit.humanize_key_ignored.join('|')}).*}
+
+      if Lit.included_keys.is_a?(String)
+        keys = Lit.included_keys.split(',').map(&:strip)
+        Lit.included_keys = keys
+      end
+      Lit.included_keys = [] unless Lit.included_keys.is_a?(Array)
+
       if Lit.ignored_keys.is_a?(String)
         keys = Lit.ignored_keys.split(',').map(&:strip)
         Lit.ignored_keys = keys

lib/lit/i18n_backend.rb

@@ -177,7 +177,9 @@ def valid_locale?(locale)
     end
 
     def is_ignored_key(key_without_locale)
-      Lit.ignored_keys.any?{ |k| key_without_locale.start_with?(k) }
+      return true  if Lit.included_keys.any? && !Lit.included_keys.any?{ |k| key_without_locale.start_with?(k) }
+
+      Lit.ignored_keys.any?{ |k| key_without_locale.start_with?(k) }      
     end
 
     def should_cache?(key_with_locale, options)

test/unit/lit_behaviour_test.rb

@@ -121,6 +121,40 @@ def teardown
     Lit.loader = old_loader
   end
 
+
+  test 'it wont store key if prefix is added to ignored, but in included keys' do
+    old_loader = Lit.loader
+    key = 'test.of.storage'
+    existing_key = 'existing.string'
+    Lit.included_keys = ['existing']
+    Lit.loader = nil
+    Lit.init
+    I18n.t(key)
+    I18n.t(existing_key)
+    assert !Lit::LocalizationKey.where(localization_key: key).exists?
+    assert Lit::LocalizationKey.where(localization_key: existing_key).exists?
+    Lit.loader = old_loader
+  end
+
+  test 'it wont store key if prefix is added to ignored, but not in included keys' do
+    old_loader = Lit.loader
+    included_key = 'test.of.storage'
+    ignored_key = 'test.of.storage2'
+    ignored_key2 = 'existing.string'
+    Lit.included_keys = ['test']
+    Lit.ignored_keys = ['test.of.storage2']
+    Lit.loader = nil
+    Lit.init
+    I18n.t(included_key)
+    I18n.t(ignored_key)
+    I18n.t(ignored_key2)
+    assert !Lit::LocalizationKey.where(localization_key: ignored_key).exists?
+    assert !Lit::LocalizationKey.where(localization_key: ignored_key2).exists?
+    assert Lit::LocalizationKey.where(localization_key: included_key).exists?
+    Lit.loader = old_loader
+  end
+
+
   test 'it wont store key if ignored_key prefix is a string' do
     old_loader = Lit.loader
     first_key = 'test.of.storage'