Revised the pagination utility to handle the empty data. better

This commit is contained in:
依瑪貓 2023-02-04 12:19:30 +08:00
parent a7a432914d
commit fd63149066
2 changed files with 69 additions and 41 deletions

View File

@ -59,15 +59,15 @@ class Redirection(RequestRedirect):
"""The HTTP code.""" """The HTTP code."""
DEFAULT_PAGE_SIZE: int = 10
"""The default page size."""
T = t.TypeVar("T") T = t.TypeVar("T")
class Pagination(t.Generic[T]): class Pagination(t.Generic[T]):
"""The pagination utilities""" """The pagination utility."""
AVAILABLE_PAGE_SIZES: list[int] = [10, 100, 200]
"""The available page sizes."""
DEFAULT_PAGE_SIZE: int = 10
"""The default page size."""
def __init__(self, items: list[T], is_reversed: bool = False): def __init__(self, items: list[T], is_reversed: bool = False):
"""Constructs the pagination. """Constructs the pagination.
@ -77,32 +77,75 @@ class Pagination(t.Generic[T]):
otherwise. otherwise.
:raise Redirection: When the pagination parameters are malformed. :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 \ self.__current_uri: str = request.full_path if request.query_string \
else request.path else request.path
"""The current URI.""" """The current URI."""
self.__items: list[T] = items
"""All the items."""
self.__is_reversed: bool = is_reversed self.__is_reversed: bool = is_reversed
"""Whether the default page is the last page.""" """Whether the default page is the last page."""
self.__page_size: int = self.__get_page_size() self.__page_size: int = self.__get_page_size()
"""The number of items in a page.""" """The number of items in a page."""
self.__total_pages: int = 0 if len(items) == 0 \ self.__total_pages: int = int((len(items) - 1) / self.__page_size) + 1
else int((len(items) - 1) / self.__page_size) + 1
"""The total number of pages.""" """The total number of pages."""
self.is_paged: bool = self.__total_pages > 1 self.is_paged = self.__total_pages > 1
"""Whether there should be pagination.""" self.__default_page_no: int = self.__total_pages \
self.__default_page_no: int = 0 if self.__is_reversed else 1
"""The default page number.""" """The default page number."""
self.__page_no: int = 0 self.__page_no: int = self.__get_page_no()
"""The current page number.""" """The current page number."""
self.list: list[T] = [] lower_bound: int = (self.__page_no - 1) * self.__page_size
"""The items shown in the list""" upper_bound: int = lower_bound + self.__page_size
if self.__total_pages > 0: if upper_bound > len(items):
self.__set_list() upper_bound = len(items)
self.page_links: list[Link] = self.__get_page_links() self.list = items[lower_bound:upper_bound]
"""The pagination links.""" self.page_links = self.__get_page_links()
self.page_sizes: list[Link] = self.__get_page_sizes() self.page_sizes = self.__get_page_sizes()
"""The links to switch the number of items in a page."""
def __get_page_size(self) -> int: def __get_page_size(self) -> int:
"""Returns the page size. """Returns the page size.
@ -111,29 +154,15 @@ class Pagination(t.Generic[T]):
:raise Redirection: When the page size is malformed. :raise Redirection: When the page size is malformed.
""" """
if "page-size" not in request.args: if "page-size" not in request.args:
return self.DEFAULT_PAGE_SIZE return DEFAULT_PAGE_SIZE
try: try:
page_size: int = int(request.args["page-size"]) page_size: int = int(request.args["page-size"])
except ValueError: except ValueError:
raise Redirection(self.__uri_set("page-size", None)) 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)) raise Redirection(self.__uri_set("page-size", None))
return page_size 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: def __get_page_no(self) -> int:
"""Returns the page number. """Returns the page number.
@ -255,7 +284,7 @@ class Pagination(t.Generic[T]):
""" """
if page_size == self.__page_size: if page_size == self.__page_size:
return self.__current_uri 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", None)
return self.__uri_set("page-size", str(page_size)) return self.__uri_set("page-size", str(page_size))

View File

@ -24,7 +24,7 @@ import httpx
from flask import Flask, request from flask import Flask, request
from accounting.utils.next_url import append_next, inherit_next, or_next 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 accounting.utils.query import parse_query_keywords
from test_site import create_app from test_site import create_app
from testlib import get_csrf_token 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", self.__test_malformed("q=word&page-size=100a&page-no=37&next=%2F",
range(1, 691), "q=word&page-no=37&next=%2F") range(1, 691), "q=word&page-no=37&next=%2F")
# A default page size # A default page size
self.__test_malformed("q=word" self.__test_malformed(f"q=word&page-size={DEFAULT_PAGE_SIZE}"
f"&page-size={Pagination.DEFAULT_PAGE_SIZE}"
"&page-no=37&next=%2F", "&page-no=37&next=%2F",
range(1, 691), "q=word&page-no=37&next=%2F") range(1, 691), "q=word&page-no=37&next=%2F")
# An invalid page size # An invalid page size