Fixes #38939 - host_param macro & transient parameters

:host_param macro now allows rendering host parameters
that are assigned to the host, but are not in the database.

Background
Transient (new) host parameters associated with the host are not rendered
in the template check action nor in the 'Orchestration:Templates' queue.

This behavior causes issues for image-based provisioning when the activation key
is defined on the host level, rather than on the hostgroup.

Fixed scenarios
* 'host_param' macro now renders all host parameters
* 'hosts#template_used' action now renders templates with all host parameters
* 'Orchestration::Templates' now renders templates with all host parameters

Links
* Community RFC: https://community.theforeman.org/t/provisioning-hosts-doesnt-work-well-with-host-parameters/44334
* Original ticket: https://projects.theforeman.org/issues/38422

Author: stejskalleos

app/models/concerns/host_params.rb

@@ -21,7 +21,11 @@ def inherited_params_hash
     end
 
     def non_inherited_params_hash
-      params_to_hash(host_parameters.authorized(:view_params))
+      items = host_parameters.authorized(:view_params).to_a
+      # Add transient host parameters to the array
+      # :authorized removes records that are not saved in the db
+      items += host_parameters.reject(&:persisted?) if User.current.can?(:view_params)
+      params_to_hash(items.uniq(&:name))
     end
 
     def params_to_hash(params)

test/controllers/hosts_controller_test.rb

@@ -1128,28 +1128,52 @@ class Host::Valid < Host::Managed; end
   describe '#template_used' do
     setup do
       @host.setBuild
-      ActiveRecord::Base.any_instance.expects(:destroy).never
-      ActiveRecord::Base.any_instance.expects(:save).never
       @attrs = host_attributes(@host)
       @attrs['hostgroup_id'] = hostgroups(:common).id
     end
 
     test 'returns templates with interfaces' do
+      ActiveRecord::Base.any_instance.expects(:destroy).never
+      ActiveRecord::Base.any_instance.expects(:save).never
+
       nic = FactoryBot.build(:nic_managed, :host => @host)
       @attrs[:interfaces_attributes] = nic.attributes.except 'updated_at', 'created_at', 'attrs'
       put :template_used, params: {:provisioning => 'build', :host => @attrs, :id => @host.id }, session: set_session_user, xhr: true
       assert_response :success
       assert_template :partial => '_provisioning'
     end
 
-    test 'returns templates with host parameters' do
-      @attrs[:host_parameters_attributes] = {'0' => {:name => 'foo', :value => 'bar'}}
-      put :template_used, params: {:provisioning => 'build', :host => @attrs }, session: set_session_user
+    test 'render templates with host parameters' do
+      template_kind = TemplateKind.find_by_name('provision')
+      template_with_error = FactoryBot.create :provisioning_template,
+        name: 'fail_without_hp_parameter',
+        template: "<% raise 'BOOOM' if host_param('transient-hp', '').empty? -%>",
+        template_kind: template_kind
+      os = FactoryBot.create(:operatingsystem, :with_archs, :with_os_defaults, provisioning_templates: [template_with_error])
+      host = FactoryBot.create(:host, :managed, operatingsystem: os)
+      attrs = host_attributes(host)
+
+      ActiveRecord::Base.any_instance.expects(:destroy).never
+      ActiveRecord::Base.any_instance.expects(:save).never
+
+      put :template_used, params: {:provisioning => 'build', :host => attrs }, session: set_session_user
+      assert_response :success
+      assert_template :partial => '_provisioning'
+      assert response.body.include? 'Templates rendered with errors'
+      assert response.body.include? 'BOOOM'
+
+      attrs[:host_parameters_attributes] = {'0' => {:name => 'transient-hp', :value => 'i-am-not-saved-in-db'}}
+      put :template_used, params: {:provisioning => 'build', :host => attrs }, session: set_session_user
       assert_response :success
       assert_template :partial => '_provisioning'
+      refute response.body.include? 'Templates rendered with errors'
+      refute response.body.include? 'BOOOM'
     end
 
     test 'shows templates for image provisioning' do
+      ActiveRecord::Base.any_instance.expects(:destroy).never
+      ActiveRecord::Base.any_instance.expects(:save).never
+
       image = compute_resources(:one).images.first
       @attrs[:compute_resource_id] = compute_resources(:one).id
       @attrs[:operatingsystem_id] = image.operatingsystem.id

test/models/concerns/host_params_test.rb

@@ -0,0 +1,48 @@
+require 'test_helper'
+
+class HostParamsTest < ActiveSupport::TestCase
+  test 'shows global params' do
+    host = FactoryBot.build_stubbed(:host)
+
+    FactoryBot.create(:common_parameter, :name => 'test_param1', :value => 'test_value1')
+
+    assert_equal 'test_value1', host.host_params['test_param1']
+  end
+
+  test 'renders global params if template specified' do
+    host = FactoryBot.build_stubbed(:host)
+    # rubocop:disable Lint/InterpolationCheck
+    FactoryBot.create(:common_parameter, :name => 'test_param1', :value => '<%= "test_value1-#{@host.name}" %>')
+    # rubocop:enable Lint/InterpolationCheck
+
+    assert_equal "test_value1-#{host.name}", host.host_params['test_param1']
+  end
+
+  test 'transient host parameters in host_params' do
+    host = FactoryBot.build(:host)
+    hp = FactoryBot.build(:host_parameter, name: 'transient-hp', value: 'i-am-not-saved-in-db')
+    host.host_parameters << hp
+
+    assert host.host_params.key? hp.name
+    assert_equal hp.value, host.host_params[hp.name]
+
+    assert host.host_params_hash.key? hp.name
+    assert_equal hp.value, host.host_params_hash.dig(hp.name, :value)
+  end
+
+  test 'transient host params without :view_params permission' do
+    user_role = FactoryBot.create(:user_user_role)
+
+    as_user user_role.owner do
+      host = FactoryBot.build(:host)
+      hp = FactoryBot.build(:host_parameter, name: 'transient-hp', value: 'i-am-not-saved-in-db')
+      host.host_parameters << hp
+
+      refute host.host_params.key? hp.name
+      assert host.host_params.key? parameters(:common).name
+
+      refute host.host_params_hash.key? hp.name
+      assert host.host_params_hash.key? parameters(:common).name
+    end
+  end
+end

test/models/host_test.rb

@@ -3381,24 +3381,6 @@ def to_managed!
     end
   end
 
-  describe 'HostParams module' do
-    test 'shows global params' do
-      host = FactoryBot.build_stubbed(:host)
-      FactoryBot.create(:common_parameter, :name => 'test_param1', :value => 'test_value1')
-
-      assert_equal 'test_value1', host.host_params['test_param1']
-    end
-
-    test 'renders global params if template specified' do
-      host = FactoryBot.build_stubbed(:host)
-      # rubocop:disable Lint/InterpolationCheck
-      FactoryBot.create(:common_parameter, :name => 'test_param1', :value => '<%= "test_value1-#{@host.name}" %>')
-      # rubocop:enable Lint/InterpolationCheck
-
-      assert_equal "test_value1-#{host.name}", host.host_params['test_param1']
-    end
-  end
-
   test "should find smart proxy ids" do
     host_1 = FactoryBot.create(:host, :with_tftp_orchestration)
     host_2 = FactoryBot.create(:host, :with_dns_orchestration)

test/unit/orchestration/templates_test.rb

@@ -27,4 +27,21 @@ class TemplatesTest < ActiveSupport::TestCase
     assert_equal 1, @queue.count
     refute @host.set_renderability
   end
+
+  test 'with transient host parameter' do
+    template = FactoryBot.build :provisioning_template,
+      name: 'fail_without_hp_parameter',
+      template: "<% raise 'BOOOM' if host_param('transient-hp', '').empty? -%>"
+    @host.stubs(:provisioning_template).returns(template)
+
+    @host.queue_render_checks
+    assert_equal 1, @queue.count
+    refute @host.set_renderability
+
+    @host.clear_host_parameters_cache!
+    @host.host_parameters << FactoryBot.build(:host_parameter, name: 'transient-hp', value: 'i-am-not-saved-in-db')
+    @host.queue_render_checks
+    assert_equal 1, @queue.count
+    assert @host.set_renderability
+  end
 end