From fd6314906600eef339390d4ec4f3cf12902fb91d Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=E4=BE=9D=E7=91=AA=E8=B2=93?= Date: Sat, 4 Feb 2023 12:19:30 +0800 Subject: [PATCH] Revised the pagination utility to handle the empty data. better --- src/accounting/utils/pagination.py | 105 ++++++++++++++++++----------- tests/test_utils.py | 5 +- 2 files changed, 69 insertions(+), 41 deletions(-) diff --git a/src/accounting/utils/pagination.py b/src/accounting/utils/pagination.py index 0afaf84..90cbc91 100644 --- a/src/accounting/utils/pagination.py +++ b/src/accounting/utils/pagination.py @@ -59,15 +59,15 @@ class Redirection(RequestRedirect): """The HTTP code.""" +DEFAULT_PAGE_SIZE: int = 10 +"""The default page size.""" + + T = t.TypeVar("T") class Pagination(t.Generic[T]): - """The pagination utilities""" - AVAILABLE_PAGE_SIZES: list[int] = [10, 100, 200] - """The available page sizes.""" - DEFAULT_PAGE_SIZE: int = 10 - """The default page size.""" + """The pagination utility.""" def __init__(self, items: list[T], is_reversed: bool = False): """Constructs the pagination. @@ -77,32 +77,75 @@ class Pagination(t.Generic[T]): otherwise. :raise Redirection: When the pagination parameters are malformed. """ + pagination: AbstractPagination[T] = EmptyPagination[T]() \ + if len(items) == 0 \ + else NonEmptyPagination[T](items, is_reversed) + self.is_paged: bool = pagination.is_paged + """Whether there should be pagination.""" + self.list: list[T] = pagination.list + """The items shown in the list""" + self.page_links: list[Link] = pagination.page_links + """The pagination links.""" + self.page_sizes: list[Link] = pagination.page_sizes + """The links to switch the number of items in a page.""" + + +class AbstractPagination(t.Generic[T]): + """An abstract pagination.""" + + def __init__(self): + """Constructs an empty pagination.""" + self.is_paged: bool = False + """Whether there should be pagination.""" + self.list: list[T] = [] + """The items shown in the list""" + self.page_links: list[Link] = [] + """The pagination links.""" + self.page_sizes: list[Link] = [] + """The links to switch the number of items in a page.""" + + +class EmptyPagination(AbstractPagination[T]): + """The pagination from empty data.""" + pass + + +class NonEmptyPagination(AbstractPagination[T]): + """The pagination with real data.""" + AVAILABLE_PAGE_SIZES: list[int] = [10, 100, 200] + """The available page sizes.""" + + def __init__(self, items: list[T], is_reversed: bool = False): + """Constructs the pagination. + + :param items: The items. + :param is_reversed: True if the default page is the last page, or False + otherwise. + :raise Redirection: When the pagination parameters are malformed. + """ + super().__init__() self.__current_uri: str = request.full_path if request.query_string \ else request.path """The current URI.""" - self.__items: list[T] = items - """All the items.""" self.__is_reversed: bool = is_reversed """Whether the default page is the last page.""" self.__page_size: int = self.__get_page_size() """The number of items in a page.""" - self.__total_pages: int = 0 if len(items) == 0 \ - else int((len(items) - 1) / self.__page_size) + 1 + self.__total_pages: int = int((len(items) - 1) / self.__page_size) + 1 """The total number of pages.""" - self.is_paged: bool = self.__total_pages > 1 - """Whether there should be pagination.""" - self.__default_page_no: int = 0 + self.is_paged = self.__total_pages > 1 + self.__default_page_no: int = self.__total_pages \ + if self.__is_reversed else 1 """The default page number.""" - self.__page_no: int = 0 + self.__page_no: int = self.__get_page_no() """The current page number.""" - self.list: list[T] = [] - """The items shown in the list""" - if self.__total_pages > 0: - self.__set_list() - self.page_links: list[Link] = self.__get_page_links() - """The pagination links.""" - self.page_sizes: list[Link] = self.__get_page_sizes() - """The links to switch the number of items in a page.""" + lower_bound: int = (self.__page_no - 1) * self.__page_size + upper_bound: int = lower_bound + self.__page_size + if upper_bound > len(items): + upper_bound = len(items) + self.list = items[lower_bound:upper_bound] + self.page_links = self.__get_page_links() + self.page_sizes = self.__get_page_sizes() def __get_page_size(self) -> int: """Returns the page size. @@ -111,29 +154,15 @@ class Pagination(t.Generic[T]): :raise Redirection: When the page size is malformed. """ if "page-size" not in request.args: - return self.DEFAULT_PAGE_SIZE + return DEFAULT_PAGE_SIZE try: page_size: int = int(request.args["page-size"]) except ValueError: raise Redirection(self.__uri_set("page-size", None)) - if page_size == self.DEFAULT_PAGE_SIZE or page_size < 1: + if page_size == DEFAULT_PAGE_SIZE or page_size < 1: raise Redirection(self.__uri_set("page-size", None)) return page_size - def __set_list(self) -> None: - """Sets the items to show in the list. - - :return: None. - """ - self.__default_page_no = self.__total_pages if self.__is_reversed \ - else 1 - self.__page_no = self.__get_page_no() - lower_bound: int = (self.__page_no - 1) * self.__page_size - upper_bound: int = lower_bound + self.__page_size - if upper_bound > len(self.__items): - upper_bound = len(self.__items) - self.list = self.__items[lower_bound:upper_bound] - def __get_page_no(self) -> int: """Returns the page number. @@ -255,7 +284,7 @@ class Pagination(t.Generic[T]): """ if page_size == self.__page_size: return self.__current_uri - if page_size == self.DEFAULT_PAGE_SIZE: + if page_size == DEFAULT_PAGE_SIZE: return self.__uri_set("page-size", None) return self.__uri_set("page-size", str(page_size)) diff --git a/tests/test_utils.py b/tests/test_utils.py index e40a0ff..81fa402 100644 --- a/tests/test_utils.py +++ b/tests/test_utils.py @@ -24,7 +24,7 @@ import httpx from flask import Flask, request from accounting.utils.next_url import append_next, inherit_next, or_next -from accounting.utils.pagination import Pagination +from accounting.utils.pagination import Pagination, DEFAULT_PAGE_SIZE from accounting.utils.query import parse_query_keywords from test_site import create_app from testlib import get_csrf_token @@ -272,8 +272,7 @@ class PaginationTestCase(unittest.TestCase): self.__test_malformed("q=word&page-size=100a&page-no=37&next=%2F", range(1, 691), "q=word&page-no=37&next=%2F") # A default page size - self.__test_malformed("q=word" - f"&page-size={Pagination.DEFAULT_PAGE_SIZE}" + self.__test_malformed(f"q=word&page-size={DEFAULT_PAGE_SIZE}" "&page-no=37&next=%2F", range(1, 691), "q=word&page-no=37&next=%2F") # An invalid page size