ironic/ironic/api/controllers/v1/collection.py

88 lines
2.9 KiB
Python

# Copyright 2013 Red Hat, Inc.
# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
from ironic import api
from ironic.api.controllers import link
def has_next(collection, limit):
"""Return whether collection has more items."""
return len(collection) and len(collection) == limit
def list_convert_with_links(items, item_name, limit, url=None, fields=None,
sanitize_func=None, key_field='uuid', **kwargs):
"""Build a collection dict including the next link for paging support.
:param items:
List of unsanitized items to include in the collection
:param item_name:
Name of dict key for items value
:param limit:
Paging limit
:param url:
Base URL for building next link
:param fields:
Optional fields to use for sanitize function
:param sanitize_func:
Optional sanitize function run on each item
:param key_field:
Key name for building next URL
:param kwargs:
other arguments passed to ``get_next``
:returns:
A dict containing ``item_name`` and ``next`` values
"""
items_dict = {
item_name: items
}
next_uuid = get_next(
items, limit, url=url, fields=fields, key_field=key_field, **kwargs)
if next_uuid:
items_dict['next'] = next_uuid
if sanitize_func:
for item in items:
sanitize_func(item, fields=fields)
return items_dict
def get_next(collection, limit, url=None, key_field='uuid', **kwargs):
"""Return a link to the next subset of the collection."""
if not has_next(collection, limit):
return None
fields = kwargs.pop('fields', None)
# NOTE(saga): If fields argument is present in kwargs and not None. It
# is a list so convert it into a comma seperated string.
if fields:
kwargs['fields'] = ','.join(fields)
q_args = ''.join(['%s=%s&' % (key, kwargs[key]) for key in kwargs])
last_item = collection[-1]
# handle items which are either objects or dicts
if hasattr(last_item, key_field):
marker = getattr(last_item, key_field)
else:
marker = last_item.get(key_field)
next_args = '?%(args)slimit=%(limit)d&marker=%(marker)s' % {
'args': q_args, 'limit': limit,
'marker': marker}
return link.make_link('next', api.request.public_url,
url, next_args)['href']