Support cancellation for miq_request and miq_request_task

app/models/miq_request.rb

@@ -590,6 +590,14 @@ def self.display_name(number = 1)
     n_('Request', 'Requests', number)
   end
 
+  def cancel
+    raise _("Cancel operation is not supported for #{self.class.name}")
+  end
+
+  def canceling?
+    false
+  end
+
   private
 
   def clean_up_keys_for_request_task

app/models/miq_request_task.rb

@@ -206,6 +206,14 @@ def self.display_name(number = 1)
     n_('Request Task', 'Request Tasks', number)
   end
 
+  def cancel
+    raise _("Cancel operation is not supported for #{self.class.name}")
+  end
+
+  def canceling?
+    false
+  end
+
   private
 
   def validate_request_type

app/models/service_template_transformation_plan_request.rb

@@ -23,4 +23,14 @@ def validate_vm(_vm_id)
   def approve_vm(vm_id)
     vm_resources.find_by(:resource_id => vm_id).update_attributes!(:status => ServiceResource::STATUS_APPROVED)
   end
+
+  def cancel
+    options['cancel_requested'] = true
+    save!
+    miq_request_tasks.each(&:cancel)
+  end
+
+  def canceling?
+    options['cancel_requested']
+  end
 end

app/models/service_template_transformation_plan_task.rb

@@ -102,6 +102,15 @@ def transformation_log_queue(userid = nil)
     MiqTask.generic_action_with_callback(options, queue_options)
   end
 
+  def cancel
+    options['cancel_requested'] = true
+    save!
+  end
+
+  def canceling?
+    options['cancel_requested']
+  end
+
   private
 
   def vm_resource