Replaced the CashReportView list view with the cash view function, to simplify. Moved the pagination query parameter parser from the view to Pagination.

accounting/urls.py

@@ -43,7 +43,7 @@ urlpatterns = [
     path("", views.home, name="home"),
     path("cash", views.cash_home, name="cash.home"),
     path("cash/<str:subject_code>/<str:period_spec>",
-         views.CashReportView.as_view(), name="cash"),
+         views.cash, name="cash"),
     path("cash-summary",
          mia_core_views.todo, name="cash-summary.home"),
     path("cash-summary/<str:subject_code>",

accounting/views/__init__.py

@@ -18,24 +18,20 @@
 """The view controllers of the accounting application.
 
 """
-from datetime import date
-
-from django.http import HttpResponseRedirect, HttpResponse
 
+from django.http import HttpResponseRedirect
+from django.shortcuts import render
 from django.urls import reverse
 from django.utils import dateformat
-from django.utils.decorators import method_decorator
 from django.utils.timezone import localdate
 from django.utils.translation import get_language, pgettext
-from django.views import generic
 from django.views.decorators.http import require_GET
 
 from accounting.models import Record, Transaction, Subject
-from mia_core.period import Period
 from mia import settings
 from mia_core.digest_auth import digest_login_required
-from mia_core.utils import UrlBuilder, Pagination, \
+from mia_core.period import Period
-    PageNoOutOfRangeException
+from mia_core.utils import Pagination
 
 
 @require_GET
@@ -65,99 +61,22 @@ def cash_home(request):
         reverse("accounting:cash", args=(subject_code, period_spec)))
 
 
-@method_decorator(digest_login_required, name='dispatch')
+@require_GET
-class BaseReportView(generic.ListView):
+@digest_login_required
-    """A base account report.
+def cash(request, subject_code, period_spec):
-
+    """The cash account report."""
-    Attributes:
-        page_no (int): The specified page number
-        page_size (int): The specified page size
-        period (Period): The template period helper
-        subject (Subject): The currently-specified subject
-    """
-    page_no = None
-    page_size = None
-    pagination = None
-    period = None
-    subject = None
-
-    def get(self, request, *args, **kwargs):
-        """Adds object_list to the context.
-
-        Args:
-            request (HttpRequest): The request.
-            args (list): The remaining arguments.
-            kwargs (dict): The keyword arguments.
-
-        Returns:
-            The response
-        """
-        if request.user.is_anonymous:
-            return HttpResponse(status=401)
-        try:
-            self.page_size = int(request.GET["page-size"])
-            if self.page_size < 1:
-                return HttpResponseRedirect(
-                    str(UrlBuilder(request.get_full_path())
-                        .del_param("page-size")))
-        except KeyError:
-            self.page_size = None
-        except ValueError:
-            return HttpResponseRedirect(
-                    str(UrlBuilder(request.get_full_path())
-                        .del_param("page-size")))
-        try:
-            self.page_no = int(request.GET["page"])
-            if self.page_no < 1:
-                return HttpResponseRedirect(
-                    str(UrlBuilder(request.get_full_path())
-                        .del_param("page")))
-        except KeyError:
-            self.page_no = None
-        except ValueError:
-            return HttpResponseRedirect(
-                str(UrlBuilder(request.get_full_path())
-                    .del_param("page")))
-        try:
-            r = super(BaseReportView, self) \
-                .get(request, *args, **kwargs)
-        except PageNoOutOfRangeException:
-            return HttpResponseRedirect(
-                str(UrlBuilder(request.get_full_path())
-                    .del_param("page")))
-        return r
-
-    def get_context_data(self, **kwargs):
-        data = super(BaseReportView, self).get_context_data(**kwargs)
-        data["period"] = self.period
-        data["subject"] = self.subject
-        data["pagination"] = self.pagination
-        return data
-
-
-class CashReportView(BaseReportView):
-    """The accounting cash report."""
-    http_method_names = ["get"]
-    template_name = "accounting/cash.html"
-    context_object_name = "records"
-
-    def get_queryset(self):
-        """Return the accounting records for the cash report.
-
-        Returns:
-            List[Record]: The accounting records for the cash report
-        """
     first_txn = Transaction.objects.order_by("date").first()
     data_start = first_txn.date if first_txn is not None else None
     last_txn = Transaction.objects.order_by("-date").first()
     data_end = last_txn.date if last_txn is not None else None
-        self.period = Period(
+    period = Period(
         get_language(), data_start, data_end,
-            self.kwargs["period_spec"])
+        period_spec)
-        if self.kwargs["subject_code"] == "0":
+    # The list data
-            self.subject = Subject(code="0")
+    if subject_code == "0":
-            self.subject.title_zhtw = pgettext(
+        subject = Subject(code="0")
-                "Accounting|", "Current assets and liabilities")
+        subject.title_zhtw = pgettext(
+            "Accounting|", "Current Assets And Liabilities")
         records = Record.objects.raw(
             """SELECT r.*
 FROM accounting_records AS r
@@ -188,10 +107,9 @@ ORDER BY
   t.ord,
   CASE WHEN is_credit THEN 1 ELSE 2 END,
   r.ord""",
-                [self.period.start, self.period.end])
+            [period.start, period.end])
     else:
-            self.subject = Subject.objects.filter(
+        subject = Subject.objects.filter(code=subject_code).first()
-                code=self.kwargs["subject_code"]).first()
         records = Record.objects.raw(
             """SELECT r.*
 FROM accounting_records AS r
@@ -216,11 +134,14 @@ ORDER BY
   t.ord,
   CASE WHEN is_credit THEN 1 ELSE 2 END,
   r.ord""",
-                [self.period.start,
+            [period.start,
-                 self.period.end,
+             period.end,
-                 self.subject.code + "%",
+             subject.code + "%",
-                 self.subject.code + "%"])
+             subject.code + "%"])
-        self.pagination = Pagination(
+    pagination = Pagination(request, records, True)
-            self.request.get_full_path(), records,
+    return render(request, "accounting/cash.html", {
-            self.page_no, self.page_size, True)
+        "records": pagination.records,
-        return self.pagination.records
+        "pagination": pagination,
+        "subject": subject,
+        "period": period,
+    })

mia_core/utils.py

@@ -46,10 +46,10 @@ class UrlBuilder:
             return
         self.base_path = start_url[:pos]
         self.params = []
-        for piece in start_url[pos+1:].split("&"):
+        for piece in start_url[pos + 1:].split("&"):
             pos = piece.find("=")
             name = urllib.parse.unquote(piece[:pos])
-            value = urllib.parse.unquote(piece[pos+1:])
+            value = urllib.parse.unquote(piece[pos + 1:])
             self.params.append(self.Param(name, value))
 
     def add_param(self, name, value):
@@ -143,14 +143,11 @@ class UrlBuilder:
                 urllib.parse.quote(self.value))
 
 
-DEFAULT_PAGE_SIZE = 10
-
-
 class Pagination:
     """The pagination.
 
     Args:
-        current_url (str): The current URL
+        request (HttpRequest): The request
         records (list[Model]): All the records
         page_no (int): The specified page number
         page_size (int): The specified number of records per page
@@ -158,8 +155,7 @@ class Pagination:
                             page first
 
     Raises:
-        PageNoOutOfRangeError: if the specified page number is out
+        PaginationException: With invalid pagination parameters
-            of range or is redundant.
 
     Attributes:
         is_reversed (bool): Whether we should display the last
@@ -182,30 +178,57 @@ class Pagination:
     page_no = None
     records = None
 
-    def __init__(self, current_url, records, page_no,
+    DEFAULT_PAGE_SIZE = 10
-                 page_size, is_reversed=False):
+
+    def __init__(self, request, records, is_reversed=False):
+        current_url = request.get_full_path()
         self._current_url = current_url
-        self._base_url = UrlBuilder(current_url).del_param("page")
         self.is_reversed = is_reversed
-        self.page_size = page_size \
+
-            if page_size is not None \
+        # The page size
-            else DEFAULT_PAGE_SIZE
+        try:
+            self.page_size = int(request.GET["page-size"])
+            if self.page_size == self.DEFAULT_PAGE_SIZE:
+                raise PaginationException(str(
+                    UrlBuilder(current_url).del_param("page-size")))
+            if self.page_size < 1:
+                raise PaginationException(str(
+                    UrlBuilder(current_url).del_param("page-size")))
+        except KeyError:
+            self.page_size = self.DEFAULT_PAGE_SIZE
+        except ValueError:
+            raise PaginationException(str(
+                UrlBuilder(current_url).del_param("page-size")))
         self.total_pages = int(
             (len(records) - 1) / self.page_size) + 1
+        default_page_no = 1 if not is_reversed else self.total_pages
         self.is_paged = self.total_pages > 1
+
+        # The page number
+        try:
+            self.page_no = int(request.GET["page"])
+            if not self.is_paged:
+                raise PaginationException(str(
+                    UrlBuilder(current_url).del_param("page")))
+            if self.page_no == default_page_no:
+                raise PaginationException(str(
+                    UrlBuilder(current_url).del_param("page")))
+            if self.page_no < 1:
+                raise PaginationException(str(
+                    UrlBuilder(current_url).del_param("page")))
+            if self.page_no > self.total_pages:
+                raise PaginationException(str(
+                    UrlBuilder(current_url).del_param("page")))
+        except KeyError:
+            self.page_no = default_page_no
+        except ValueError:
+            raise PaginationException(str(
+                UrlBuilder(current_url).del_param("page")))
+
         if not self.is_paged:
             self.page_no = 1
             self.records = records
-            self._links = []
             return
-        default_page = 1 if not is_reversed else self.total_pages
-        if page_no == default_page:
-            raise PageNoOutOfRangeException()
-        self.page_no = page_no \
-            if page_no is not None \
-            else default_page
-        if self.page_no > self.total_pages:
-            raise PageNoOutOfRangeException()
         start_no = self.page_size * (self.page_no - 1)
         self.records = records[start_no:start_no + self.page_size]
 
@@ -321,9 +344,24 @@ class Pagination:
     def page_size_options(self):
         base_url = UrlBuilder(self._current_url).del_param(
             "page").del_param("page-size")
-        return [self.PageSizeOption(x, _page_size_url(base_url, x))
+        return [self.PageSizeOption(x, self._page_size_url(base_url, x))
                 for x in [10, 100, 200]]
 
+    @staticmethod
+    def _page_size_url(base_url, size):
+        """Returns the URL for a new page size.
+
+        Args:
+            base_url (UrlBuilder): The base URL builder.
+            size (int): The new page size.
+
+        Returns:
+            str: The URL for the new page size.
+        """
+        if size == Pagination.DEFAULT_PAGE_SIZE:
+            return str(base_url)
+        return str(base_url.clone().add_param("page-size", str(size)))
+
     class PageSizeOption:
         """A page size option.
 
@@ -343,23 +381,16 @@ class Pagination:
             self.url = url
 
 
-def _page_size_url(base_url, size):
+class PaginationException(Exception):
-    """Returns the URL for a new page size.
+    """The exception thrown with invalid pagination parameters.
 
     Args:
-        base_url (UrlBuilder): The base URL builder.
+        url (str): The canonical URL to redirect to.
-        size (int): The new page size.
 
-    Returns:
+    Attributes:
-        str: The URL for the new page size.
+        url (str): The canonical URL to redirect to.
     """
-    if size == DEFAULT_PAGE_SIZE:
+    url = None
-        return str(base_url)
-    return str(base_url.clone().add_param("page-size", str(size)))
 
-
+    def __init__(self, url):
-class PageNoOutOfRangeException(Exception):
+        self.url = url
-    """The error thrown when the specified page number is out of
-    range.
-    """
-    pass