我在这里做错了什么？因为我一直无法将关键字类别解析为字段错误。
此行抛出的异常
services = services.filter(categories__category__name=category)
但是，通过查看代码，可以看到service_categories字段与ServiceCategory之间存在关联，ServiceCategoryServicePage的相关名称为“categories”。所以我认为不应该抛出无法解析字段的异常错误。在这一点上的任何帮助将非常感激。
def get_service_context(context):
context['all_categories'] = ServiceCategory.objects.all()
context['root_categories'] = ServiceCategory.objects.filter(
parent=None,
).prefetch_related(
'children',
).annotate(
service_count=Count('servicepage'),
)
return context
class ServiceIndexPage(Page):
header_image = models.ForeignKey(
'wagtailimages.Image',
null=True,
blank=True,
on_delete=models.SET_NULL,
related_name='+'
)
heading = models.CharField(max_length=500, null=True, blank=True)
sub_heading = models.CharField(max_length=500, null=True, blank=True)
body = RichTextField(null=True, blank=True)
def get_context(self, request, category=None, *args, **kwargs):
context = super(ServiceIndexPage, self).get_context(request, *args, **kwargs)
services = self.get_children().live().order_by('-first_published_at') #.prefetch_related('categories', 'categories__category')
if category is None:
if request.GET.get('category'):
category = get_object_or_404(ServiceCategory, slug=request.GET.get('category'))
if category:
if not request.GET.get('category'):
category = get_object_or_404(ServiceCategory, slug=category)
services = services.filter(categories__category__name=category)
# Pagination
page = request.GET.get('page')
page_size = 10
if hasattr(settings, 'SERVICE_PAGINATION_PER_PAGE'):
page_size = settings.SERVICE_PAGINATION_PER_PAGE
if page_size is not None:
paginator = Paginator(services, page_size) # Show 10 services per page
try:
services = paginator.page(page)
except PageNotAnInteger:
services = paginator.page(1)
except EmptyPage:
services = paginator.page(paginator.num_pages)
context['services'] = services
context['category'] = category
context = get_service_context(context)
return context
@register_snippet
class ServiceCategory(models.Model):
name = models.CharField(max_length=250, unique=True, verbose_name=_('Category Name'))
slug = models.SlugField(unique=True, max_length=250)
parent = models.ForeignKey('self', blank=True, null=True, related_name="children")
date = models.DateField(auto_now_add=True, auto_now=False, null=True, blank=True)
description = RichTextField(blank=True)
class Meta:
ordering = ['-date']
verbose_name = _("Service Category")
verbose_name_plural = _("Service Categories")
panels = [
FieldPanel('name'),
FieldPanel('parent'),
FieldPanel('description'),
]
def __str__(self):
return self.name
def clean(self):
if self.parent:
parent = self.parent
if self.parent == self:
raise ValidationError('Parent category cannot be self.')
if parent.parent and parent.parent == self:
raise ValidationError('Cannot have circular Parents.')
def save(self, *args, **kwargs):
if not self.slug:
slug = slugify(self.name)
count = ServiceCategory.objects.filter(slug=slug).count()
if count > 0:
slug = '{}-{}'.format(slug, count)
self.slug = slug
return super(ServiceCategory, self).save(*args, **kwargs)
class ServiceCategoryServicePage(models.Model):
category = models.ForeignKey(ServiceCategory, related_name="+", verbose_name=_('Category'))
page = ParentalKey('ServicePage', related_name='categories')
panels = [
FieldPanel('category'),
]
class ServicePage(Page):
header_image = models.ForeignKey(
'wagtailimages.Image',
null=True,
blank=True,
on_delete=models.SET_NULL,
related_name='+',
verbose_name=_('Header image')
)
service_title = models.CharField(max_length=300, null=True, blank=True)
body = StreamField([
('h1', CharBlock(icon="title", classanme="title")),
('h2', CharBlock(icon="title", classanme="title")),
('h3', CharBlock(icon="title", classanme="title")),
('h4', CharBlock(icon="title", classanme="title")),
('h5', CharBlock(icon="title", classanme="title")),
('h6', CharBlock(icon="title", classanme="title")),
('paragraph', RichTextBlock(icon="pilcrow")),
('aligned_image', ImageBlock(label="Aligned image", icon="image")),
('pullquote', PullQuoteBlock()),
('raw_html', RawHTMLBlock(label='Raw HTML', icon="code")),
('embed', EmbedBlock(icon="code")),
])
date = models.DateField("Post date")
service_categories = models.ManyToManyField(ServiceCategory, through=ServiceCategoryServicePage, blank=True)
feed_image = models.ForeignKey(
'wagtailimages.Image',
null=True,
blank=True,
on_delete=models.SET_NULL,
related_name='+',
verbose_name=_('Feed image')
)
search_fields = Page.search_fields + [
index.SearchField('body'),
index.SearchField('service_title'),
index.SearchField('title'),]
def get_absolute_url(self):
return self.url
def get_service_index(self):
# Find closest ancestor which is a service index
return self.get_ancestors().type(ServiceIndexPage).last()
def get_context(self, request, *args, **kwargs):
context = super(ServicePage, self).get_context(request, *args, **kwargs)
context['services'] = self.get_service_index().serviceindexpage
context = get_service_context(context)
return context
class Meta:
verbose_name = _('Service page')
verbose_name_plural = _('Services pages')
parent_page_types = ['services.ServiceIndexPage']
ServicePage.content_panels = [
FieldPanel('title', classname="full title"),
FieldPanel('service_title'),
ImageChooserPanel('header_image'),
FieldPanel('date'),
InlinePanel('categories', label=_("Categories")),
StreamFieldPanel('body'),
ImageChooserPanel('feed_image'),
]
答案 0 :(得分：1)
在线路上致电self.get_children()时：
services = self.get_children().live().order_by('-first_published_at')
结果是一个Page个对象的查询集，它只包含所有页面类型共有的基本字段，例如title - 因此，无法根据{{1}过滤此查询集}}。发生这种情况是因为Wagtail无法知道ServiceIndexPage的子页面都是ServicePages - 请参阅https://stackoverflow.com/a/46530443/1853523以获得更完整的解释。
但是，您可以按如下方式重写此行：
categories我们可以确定查询集services = ServicePage.objects.child_of(self).live().order_by('-first_published_at')
只包含ServicePage.objects.child_of(self)个对象，因此现在可以对ServicePage进行过滤。