azure.core.paging — Azure SDK for Python 2.0.0 documentation

# --------------------------------------------------------------------------## Copyright (c) Microsoft Corporation. All rights reserved.## The MIT License (MIT)## Permission is hereby granted, free of charge, to any person obtaining a copy# of this software and associated documentation files (the ""Software""), to# deal in the Software without restriction, including without limitation the# rights to use, copy, modify, merge, publish, distribute, sublicense, and/or# sell copies of the Software, and to permit persons to whom the Software is# furnished to do so, subject to the following conditions:## The above copyright notice and this permission notice shall be included in# all copies or substantial portions of the Software.## THE SOFTWARE IS PROVIDED *AS IS*, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS# IN THE SOFTWARE.## --------------------------------------------------------------------------import itertoolsfrom typing import ( # pylint: disable=unused-import Callable, Optional, TypeVar, Iterator, Iterable, Tuple, Any,)import loggingfrom .exceptions import AzureError_LOGGER = logging.getLogger(__name__)ReturnType = TypeVar("ReturnType")ResponseType = TypeVar("ResponseType")[docs]class PageIterator(Iterator[Iterator[ReturnType]]): def __init__( self, get_next: Callable[[Optional[str]], ResponseType], extract_data: Callable[[ResponseType], Tuple[str, Iterable[ReturnType]]], continuation_token: Optional[str] = None, ):"""Return an iterator of pages. :param get_next: Callable that take the continuation token and return a HTTP response :param extract_data: Callable that take an HTTP response and return a tuple continuation token, list of ReturnType :param str continuation_token: The continuation token needed by get_next """ self._get_next = get_next self._extract_data = extract_data self.continuation_token = continuation_token self._did_a_call_already = False self._response: Optional[ResponseType] = None self._current_page: Optional[Iterable[ReturnType]] = None def __iter__(self) -> Iterator[Iterator[ReturnType]]: return self def __next__(self) -> Iterator[ReturnType]: if self.continuation_token is None and self._did_a_call_already: raise StopIteration("End of paging") try: self._response = self._get_next(self.continuation_token) except AzureError as error: if not error.continuation_token: error.continuation_token = self.continuation_token raise self._did_a_call_already = True self.continuation_token, self._current_page = self._extract_data(self._response) return iter(self._current_page) next = __next__ # Python 2 compatibility. Can't be removed as some people are using ".next()" even in Py3[docs]class ItemPaged(Iterator[ReturnType]): def __init__(self, *args: Any, **kwargs: Any) -> None:"""Return an iterator of items. args and kwargs will be passed to the PageIterator constructor directly, except page_iterator_class """ self._args = args self._kwargs = kwargs self._page_iterator: Optional[Iterator[ReturnType]] = None self._page_iterator_class = self._kwargs.pop("page_iterator_class", PageIterator)[docs] def by_page(self, continuation_token: Optional[str] = None) -> Iterator[Iterator[ReturnType]]:"""Get an iterator of pages of objects, instead of an iterator of objects. :param str continuation_token: An opaque continuation token. This value can be retrieved from the continuation_token field of a previous generator object. If specified, this generator will begin returning results from this point. :returns: An iterator of pages (themselves iterator of objects) :rtype: iterator[iterator[ReturnType]] """ return self._page_iterator_class(continuation_token=continuation_token, *self._args, **self._kwargs) def __repr__(self) -> str: return "<iterator object azure.core.paging.ItemPaged at {}>".format(hex(id(self))) def __iter__(self) -> Iterator[ReturnType]: return self def __next__(self) -> ReturnType: if self._page_iterator is None: self._page_iterator = itertools.chain.from_iterable(self.by_page()) return next(self._page_iterator) next = __next__ # Python 2 compatibility. Can't be removed as some people are using ".next()" even in Py3