def set_required_metadata_variables
      set_project_id
      set_vm_id
      set_vm_name
      set_location

      # All metadata parameters must now be set.
      missing = []
      missing << 'project_id' unless @project_id
      if @platform != Platform::OTHER
        missing << 'zone' unless @zone
        missing << 'vm_id' unless @vm_id
      end
      return if missing.empty?
      raise Fluent::ConfigError,
            "Unable to obtain metadata parameters: #{missing.join(' ')}"
    end
def set_required_metadata_variables
      set_project_id
      set_vm_id
      set_vm_name
      set_location

      # All metadata parameters must now be set.
      missing = []
      missing << 'project_id' unless @project_id
      if @platform != Platform::OTHER
        missing << 'zone' unless @zone
        missing << 'vm_id' unless @vm_id
      end
      return if missing.empty?
      raise Fluent::ConfigError,
            "Unable to obtain metadata parameters: #{missing.join(' ')}"
    end
Set required variables like @project_id, @vm_id, @vm_name and @zone.