README.md edited

.venv/lib/python3.10/site-packages/django/contrib/flatpages/forms.py

@@ -0,0 +1,74 @@
+from django import forms
+from django.conf import settings
+from django.contrib.flatpages.models import FlatPage
+from django.core.exceptions import ValidationError
+from django.utils.translation import gettext
+from django.utils.translation import gettext_lazy as _
+
+
+class FlatpageForm(forms.ModelForm):
+    url = forms.RegexField(
+        label=_("URL"),
+        max_length=100,
+        regex=r"^[-\w/.~]+$",
+        help_text=_(
+            "Example: “/about/contact/”. Make sure to have leading and trailing "
+            "slashes."
+        ),
+        error_messages={
+            "invalid": _(
+                "This value must contain only letters, numbers, dots, "
+                "underscores, dashes, slashes or tildes."
+            ),
+        },
+    )
+
+    class Meta:
+        model = FlatPage
+        fields = "__all__"
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        if not self._trailing_slash_required():
+            self.fields["url"].help_text = _(
+                "Example: “/about/contact”. Make sure to have a leading slash."
+            )
+
+    def _trailing_slash_required(self):
+        return (
+            settings.APPEND_SLASH
+            and "django.middleware.common.CommonMiddleware" in settings.MIDDLEWARE
+        )
+
+    def clean_url(self):
+        url = self.cleaned_data["url"]
+        if not url.startswith("/"):
+            raise ValidationError(
+                gettext("URL is missing a leading slash."),
+                code="missing_leading_slash",
+            )
+        if self._trailing_slash_required() and not url.endswith("/"):
+            raise ValidationError(
+                gettext("URL is missing a trailing slash."),
+                code="missing_trailing_slash",
+            )
+        return url
+
+    def clean(self):
+        url = self.cleaned_data.get("url")
+        sites = self.cleaned_data.get("sites")
+
+        same_url = FlatPage.objects.filter(url=url)
+        if self.instance.pk:
+            same_url = same_url.exclude(pk=self.instance.pk)
+
+        if sites and same_url.filter(sites__in=sites).exists():
+            for site in sites:
+                if same_url.filter(sites=site).exists():
+                    raise ValidationError(
+                        _("Flatpage with url %(url)s already exists for site %(site)s"),
+                        code="duplicate_url",
+                        params={"url": url, "site": site},
+                    )
+
+        return super().clean()