Fixes #12180 - lookup_value presence validation moved from lookup_key

Global parameters can have empty values so smart variables that are also global should be allowed to accept empty values too.
The validation on lookup_value to make sure it isn't empty is in the LookupKey class therefore affecting both VariableLookupKey and PuppetClassLookupKey.
This validation should affect on the child class - PuppetClassLookupKey.

app/models/lookup_keys/lookup_key.rb

@@ -82,6 +82,10 @@ def self.find_by_name(str)
     nil
   end
 
+  def reject_invalid_lookup_values(attributes)
+    attributes[:match].empty?
+  end
+
   def audit_class
     self
   end
@@ -117,12 +121,6 @@ def path=(v)
     write_attribute(:path, using_default ? nil : v)
   end
 
-  def reject_invalid_lookup_values(attributes)
-    attributes[:match].empty? ||
-        (attributes[:value].blank? &&
-            (attributes[:use_puppet_default].nil? || attributes[:use_puppet_default] == "0"))
-  end
-
   def default_value_before_type_cast
     return read_attribute(:default_value) if errors[:default_value].present?
     value_before_type_cast default_value

app/models/lookup_value.rb

@@ -29,7 +29,7 @@ class LookupValue < ActiveRecord::Base
   scoped_search :in => :lookup_key, :on => :key, :rename => :lookup_key, :complete_value => true
 
   def value_present?
-    self.errors.add(:value, :blank) if value.nil? && !use_puppet_default
+    self.errors.add(:value, :blank) if value.to_s.empty? && !use_puppet_default && lookup_key.puppet?
   end
 
   def value=(val)

test/functional/api/v2/override_values_controller_test.rb

@@ -70,15 +70,24 @@ class Api::V2::OverrideValuesControllerTest < ActionController::TestCase
 
   [{ :value => 'xyz=10'}, { :match => 'os=string'}].each do |override_value|
     test "should not create override value without #{override_value.keys.first}" do
-      lookup_key = FactoryGirl.create(:variable_lookup_key, :puppetclass => puppetclasses(:two))
+      lookup_key = FactoryGirl.create(:puppetclass_lookup_key, :as_smart_class_param, :puppetclass => puppetclasses(:two))
       refute lookup_key.override
       assert_difference('LookupValue.count', 0) do
-        post :create, { :smart_variable_id => lookup_key.id, :override_value => override_value }
+        post :create, {:smart_class_parameter_id => lookup_key.id, :override_value => override_value}
       end
       response = ActiveSupport::JSON.decode(@response.body)
       param_not_posted = override_value.keys.first.to_s == 'match' ? 'Value' : 'Match' # The opposite of override_value is missing
       assert_match /Validation failed: #{param_not_posted} can't be blank/, response['error']['message']
       assert_response :error
     end
   end
+
+  test "should create override value without value for smart variable" do
+    lookup_key = FactoryGirl.create(:variable_lookup_key, :puppetclass => puppetclasses(:two))
+    refute lookup_key.override
+    assert_difference('LookupValue.count', 1) do
+      post :create, {:smart_variable_id => lookup_key.id, :override_value =>  { :match => 'os=string'}}
+    end
+    assert_response :success
+  end
 end

test/unit/lookup_value_test.rb

@@ -223,4 +223,26 @@ def setup
       refute_valid @value
     end
   end
+
+  context "when key type is puppetclass lookup and value is empty" do
+    def setup
+      @key = FactoryGirl.create(:puppetclass_lookup_key, :as_smart_class_param,
+                                :with_override, :with_use_puppet_default,
+                                :key_type => 'string',
+                                :puppetclass => puppetclasses(:one))
+      @value = FactoryGirl.build_stubbed(:lookup_value, :value => "",
+                                         :match => "hostgroup=Common",
+                                         :lookup_key_id => @key.id,
+                                         :use_puppet_default => true)
+    end
+
+    test "value is validated if use_puppet_default is true" do
+      assert_valid @value
+    end
+
+    test "value is not validated if use_puppet_default is false" do
+      @value.use_puppet_default = false
+      refute_valid @value
+    end
+  end
 end