def _items(self, request, do_authz=False, parent_id=None):
     """Retrieves and formats a list of elements of the requested entity."""
     # NOTE(salvatore-orlando): The following ensures that fields which
     # are needed for authZ policy validation are not stripped away by the
     # plugin before returning.
     original_fields, fields_to_add = self._do_field_list(
         api_common.list_args(request, 'fields'))
     filters = api_common.get_filters(
         request, self._attr_info,
         ['fields', 'sort_key', 'sort_dir',
          'limit', 'marker', 'page_reverse'],
         is_filter_validation_supported=self._filter_validation)
     kwargs = {'filters': filters,
               'fields': original_fields}
     sorting_helper = self._get_sorting_helper(request)
     pagination_helper = self._get_pagination_helper(request)
     sorting_helper.update_args(kwargs)
     sorting_helper.update_fields(original_fields, fields_to_add)
     pagination_helper.update_args(kwargs)
     pagination_helper.update_fields(original_fields, fields_to_add)
     if parent_id:
         kwargs[self._parent_id_name] = parent_id
     obj_getter = getattr(self._plugin, self._plugin_handlers[self.LIST])
     obj_list = obj_getter(request.context, **kwargs)
     obj_list = sorting_helper.sort(obj_list)
     obj_list = pagination_helper.paginate(obj_list)
     # Check authz
     if do_authz:
         # FIXME(salvatore-orlando): obj_getter might return references to
         # other resources. Must check authZ on them too.
         # Omit items from list that should not be visible
         tmp_list = []
         for obj in obj_list:
             self._set_parent_id_into_ext_resources_request(
                 request, obj, parent_id, is_get=True)
             if policy.check(
                     request.context, self._plugin_handlers[self.SHOW],
                     obj, plugin=self._plugin, pluralized=self._collection):
                 tmp_list.append(obj)
         obj_list = tmp_list
     # Use the first element in the list for discriminating which attributes
     # should be filtered out because of authZ policies
     # fields_to_add contains a list of attributes added for request policy
     # checks but that were not required by the user. They should be
     # therefore stripped
     fields_to_strip = fields_to_add or []
     if obj_list:
         fields_to_strip += self._exclude_attributes_by_policy(
             request.context, obj_list[0])
     collection = {self._collection:
                   [self._filter_attributes(obj,
                       fields_to_strip=fields_to_strip)
                    for obj in obj_list]}
     pagination_links = pagination_helper.get_links(obj_list)
     if pagination_links:
         collection[self._collection + "_links"] = pagination_links
     # Synchronize usage trackers, if needed
     resource_registry.resync_resource(
         request.context, self._resource, request.context.tenant_id)
     return collection

 def _items(self, request, do_authz=False, parent_id=None):
     """Retrieves and formats a list of elements of the requested entity."""
     # NOTE(salvatore-orlando): The following ensures that fields which
     # are needed for authZ policy validation are not stripped away by the
     # plugin before returning.
     original_fields, fields_to_add = self._do_field_list(api_common.list_args(request, "fields"))
     filters = api_common.get_filters(
         request, self._attr_info, ["fields", "sort_key", "sort_dir", "limit", "marker", "page_reverse"]
     )
     kwargs = {"filters": filters, "fields": original_fields}
     sorting_helper = self._get_sorting_helper(request)
     pagination_helper = self._get_pagination_helper(request)
     sorting_helper.update_args(kwargs)
     sorting_helper.update_fields(original_fields, fields_to_add)
     pagination_helper.update_args(kwargs)
     pagination_helper.update_fields(original_fields, fields_to_add)
     if parent_id:
         kwargs[self._parent_id_name] = parent_id
     obj_getter = getattr(self._plugin, self._plugin_handlers[self.LIST])
     obj_list = obj_getter(request.context, **kwargs)
     obj_list = sorting_helper.sort(obj_list)
     obj_list = pagination_helper.paginate(obj_list)
     # Check authz
     if do_authz:
         # FIXME(salvatore-orlando): obj_getter might return references to
         # other resources. Must check authZ on them too.
         # Omit items from list that should not be visible
         obj_list = [
             obj
             for obj in obj_list
             if policy.check(request.context, self._plugin_handlers[self.SHOW], obj, plugin=self._plugin)
         ]
     # Use the first element in the list for discriminating which attributes
     # should be filtered out because of authZ policies
     # fields_to_add contains a list of attributes added for request policy
     # checks but that were not required by the user. They should be
     # therefore stripped
     fields_to_strip = fields_to_add or []
     if obj_list:
         fields_to_strip += self._exclude_attributes_by_policy(request.context, obj_list[0])
     collection = {
         self._collection: [
             self._filter_attributes(request.context, obj, fields_to_strip=fields_to_strip) for obj in obj_list
         ]
     }
     pagination_links = pagination_helper.get_links(obj_list)
     if pagination_links:
         collection[self._collection + "_links"] = pagination_links
     return collection

    def _items(self, request, do_authz=False, parent_id=None):
        """Retrieves and formats a list of elements of the requested entity."""
        # NOTE(salvatore-orlando): The following ensures that fields which
        # are needed for authZ policy validation are not stripped away by the
        # plugin before returning.
        original_fields, fields_to_add = self._do_field_list(
            api_common.list_args(request, 'fields'))
        filters = api_common.get_filters(request, self._attr_info,
                                         ['fields', 'sort_key', 'sort_dir',
                                          'limit', 'marker', 'page_reverse'])
        kwargs = {'filters': filters,
                  'fields': original_fields}
        sorting_helper = self._get_sorting_helper(request)
        pagination_helper = self._get_pagination_helper(request)
        sorting_helper.update_args(kwargs)
        sorting_helper.update_fields(original_fields, fields_to_add)
        pagination_helper.update_args(kwargs)
        pagination_helper.update_fields(original_fields, fields_to_add)
        if parent_id:
            kwargs[self._parent_id_name] = parent_id
        obj_getter = getattr(self._plugin, self._plugin_handlers[self.LIST])
        obj_list = obj_getter(request.context, **kwargs)
        obj_list = sorting_helper.sort(obj_list)
        obj_list = pagination_helper.paginate(obj_list)
        # Check authz
        if do_authz:
            # FIXME(salvatore-orlando): obj_getter might return references to
            # other resources. Must check authZ on them too.
            # Omit items from list that should not be visible
            obj_list = [obj for obj in obj_list
                        if policy.check(request.context,
                                        self._plugin_handlers[self.SHOW],
                                        obj,
                                        plugin=self._plugin)]
        collection = {self._collection:
                      [self._view(request.context, obj,
                                  fields_to_strip=fields_to_add)
                       for obj in obj_list]}
        pagination_links = pagination_helper.get_links(obj_list)
        if pagination_links:
            collection[self._collection + "_links"] = pagination_links

        return collection

 def show(self, request, id, **kwargs):
     """Returns detailed information about the requested entity."""
     try:
         # NOTE(salvatore-orlando): The following ensures that fields
         # which are needed for authZ policy validation are not stripped
         # away by the plugin before returning.
         field_list, added_fields = self._do_field_list(api_common.list_args(request, "fields"))
         parent_id = kwargs.get(self._parent_id_name)
         return {
             self._resource: self._view(
                 request.context,
                 self._item(request, id, do_authz=True, field_list=field_list, parent_id=parent_id),
                 fields_to_strip=added_fields,
             )
         }
     except exceptions.PolicyNotAuthorized:
         # To avoid giving away information, pretend that it
         # doesn't exist
         raise webob.exc.HTTPNotFound()

    def _items(self, request, do_authz=False, parent_id=None):
        """Retrieves and formats a list of elements of the requested entity."""
        # NOTE(salvatore-orlando): The following ensures that fields which
        # are needed for authZ policy validation are not stripped away by the
        # plugin before returning.
        #brk(host="10.10.12.21", port=49175)
        original_fields, fields_to_add = self._do_field_list(
            api_common.list_args(request, 'fields')) #获取查询条件字段??
        filters = api_common.get_filters(request, self._attr_info,
                                         ['fields', 'sort_key', 'sort_dir',
                                          'limit', 'marker', 'page_reverse','offset'])

        # ### add by xm at 2015.9.22 权限控制
        # #LOG.debug(_("111111 222 %s"), filters)
        # #LOG.debug(_("111111 222 context: %s"), request.context.__dict__)
        # if request.context.gc_resource_type == '0':
        #     #LOG.debug(_("111111 222 context.user_id:%s  gc_resource_type:%s"),  request.context.user_id, request.context.gc_resource_type)
        #     user_id = [request.context.user_id]
        #     user_id = list(set(user_id) | set(filters.get("user_id", [])))
        #     filters.update({"user_id": user_id})
        #     #LOG.debug(_("111111 222 ddd %s"), filters)
        # #LOG.debug(_("111111 222 %s"), filters)
        # ###end by xm

        #validate create_time_first and create_time_end
        api_common.validate_update_time_range(filters)


        kwargs = {'filters': filters,
                  'fields': original_fields}

        #according to  filters params:only_statics ,get is_query_items
        is_query_items=self._get_is_query_detail_items_infos(filters)

        filters_copy=filters.copy()
        # first get resources count number by resources filters
        counter=self._get_items_count_by_filter(request=request,filters=filters_copy)

        collection={}
        if is_query_items :#this function is not only statics
        #get resources items
            obj_list=None
            pagination_helper=None
            #change from counter >=0 to counter !=0  for no method of 'get_xxx_count'
            if (counter is not None and counter != 0) or (counter is None):
                    obj_list,pagination_helper = self._get_items_by_filter_and_order_and_page(request=request
                                                                  ,kwargs=kwargs,
                                                                  original_fields=original_fields
                                                                  ,fields_to_add=fields_to_add,
                                                                  do_authz=do_authz,
                                                                  parent_id=parent_id)
            # Use the first element in the list for discriminating which attributes
            # should be filtered out because of authZ policies
            # fields_to_add contains a list of attributes added for request policy
            # checks but that were not required by the user. They should be
            # therefore stripped
            fields_to_strip = fields_to_add or []
            if obj_list:
                fields_to_strip += self._exclude_attributes_by_policy(
                    request.context, obj_list[0])

            if obj_list:
                collection = {self._collection:
                          [self._filter_attributes(
                              request.context, obj,
                              fields_to_strip=fields_to_strip)
                           for obj in obj_list]}
            else:
                 collection = {self._collection:[]}
                 counter=0
        if counter is not None and counter>=0 :
            collection["list"]={"count":counter}
        #delete by luoyibing
        #pagination_links = pagination_helper.get_links(obj_list)

        #if pagination_links:
           # collection[self._collection + "_links"] = pagination_links
        return collection