无法使用自定义刀插件中的knife vsphere插件调用

Question

我正在尝试使用自定义刀插件中的knife vsphere插件，如下所示：

Chef::Knife::VsphereVmClone.load_deps
Chef::Knife::Bootstrap.load_deps
require 'chef/knife/base_vsphere_command'
require 'chef/knife/vsphere_vm_clone.rb'
require 'rbvmomi'
require 'netaddr'                    

def self.create_instance()

  createinstance = Chef::Knife::VsphereVmClone.new
  createinstance.config['dest_folder'] = "xxxxxx"
  createinstance.config['resource_pool'] = "xxxxx"
  createinstance.config['source_vm'] = "xxxxx"
  createinstance.config['chef_node_name'] = "xxxx"
  createinstance.config['folder'] = "xxxxxx"
  Chef::Config[:knife]['dest_folder'] = "xxxxxx"
  Chef::Config[:knife]['resource_pool'] = "xxxxxxx"
  createinstance.run

end

当我尝试调用此方法时，它会因以下错误而失败，并开始显示该命令的完整帮助。

You must supply --template TEMPLATE!
knife vsphere vm clone VMNAME (options)

我无法正确实例化VsphereVmClone的对象并设置所需的值。

提供的任何指针都会有很大的帮助。