Filter中添加动态初值

Question

我想为我的 DetailView 添加 django-filter 或 django-autocomplete-light 的动态初始值。我不知道如何最好地使用 django-filter、django-autocomplete-light 或不使用第三方应用程序来构建它。

每个 JournalDetailView 都有一个依赖项下拉列表（在我的例子中，这是期刊 → 期刊年份 → 期刊卷）。依赖下拉列表与 django-autocomplete-light 一起工作，过滤器与 django-filter 一起工作。我想为期刊传递动态字段，所以我有 ForeignKey 用于期刊年份和期刊卷的依赖下拉列表

例如，在本例中我有三个字段：期刊、期刊年份和期刊卷。我想传递价值取决于日记的 DetailView。例如，对于期刊“Nature”，它将传递字段“Nature”；对于期刊“Ca-A Cancer Journal for Clinicians”，它将通过“Ca-A Cancer Journal for Clinicians”。

我有这个

我想建立这个

models.py

class Journal(models.Model):
    slug = models.SlugField(unique=True)
    name = models.CharField(max_length=100, blank=True, null=True)



class Article(models.Model, HitCountMixin):
    slug = models.SlugField(unique=True)
    journal = models.ForeignKey(
        "Journal", on_delete=models.SET_NULL, null=True, blank=True
    )
    journalyear = models.ForeignKey(
        "JournalYear", on_delete=models.SET_NULL, null=True, blank=True
    )
    journalvolume = models.ForeignKey(
        "JournalVolume", on_delete=models.SET_NULL, null=True, blank=True
    )

    def __str__(self):
        return self.title



class JournalYear(models.Model):
    journal = models.ForeignKey(
        "Journal", on_delete=models.SET_NULL, null=True, blank=True
    )
    name = models.CharField(max_length=10, blank=True, null=True)

    def __str__(self):
        return self.name


class JournalVolume(models.Model):
    journalyear = models.ForeignKey(
        "JournalYear", on_delete=models.CASCADE, blank=True, null=True
    )
    name = models.CharField(max_length=10, blank=True, null=True)

    def __str__(self):
        return self.name

views.py

class JournalAutocomplete2(autocomplete.Select2QuerySetView):
    def get_queryset(self):
        # Don't forget to filter out results depending on the visitor !
        if not self.request.user.is_authenticated:
            return Journal.objects.none()

        qs = Journal.objects.all()

        if self.q:
            qs = qs.filter(name__icontains=self.q)
            
        return qs


class JournalYearAutocomplete2(autocomplete.Select2QuerySetView):
    def get_queryset(self):
        # Don't forget to filter out results depending on the visitor !
        if not self.request.user.is_authenticated:
            return JournalYear.objects.none()

        journal = self.forwarded.get("journal")

        qs = JournalYear.objects.all()

        if journal:
            qs = qs.filter(journal=journal)

        if self.q:
            qs = qs.filter(name__icontains=self.q)

        return qs


class JournalVolumeAutocomplete2(autocomplete.Select2QuerySetView):
    def get_queryset(self):
        # Don't forget to filter out results depending on the visitor !
        if not self.request.user.is_authenticated:
            return JournalVolume.objects.none()

        qs = JournalVolume.objects.all()

        journalyear = self.forwarded.get("journalyear", None)

        if journalyear:
            qs = qs.filter(journalyear=journalyear)

        if self.q:
            qs = qs.filter(name__icontains=self.q)

        return qs

class JournalListView(ListView):
    model = Journal
    template_name = "journals/journals.html"
    context_object_name = "journals"

class JournalDetailView(DetailView):
    model = Journal
    template_name = "journals/journal_detail.html"
    context_object_name = "journal"

    def get_context_data(self, **kwargs):
        context_data = super(JournalDetailView, self).get_context_data()
        journal_slug = self.kwargs.get("slug", None)
        f = JournalFilter(
            self.request.GET,
            queryset=Article.objects.filter(
                journal__slug__exact=self.kwargs["slug"]),
        )
        context_data["filter"] = f
        return context_data

filters.py

class JournalFilter(django_filters.FilterSet):
    journal = django_filters.ModelChoiceFilter(
        queryset=Journal.objects.all(),
        widget=autocomplete.ModelSelect2(url="journalautocomplete2"),
    )
    journalyear = django_filters.ModelChoiceFilter(
        queryset=JournalYear.objects.all(),
        widget=autocomplete.ModelSelect2(
            url="journalyearautocomplete2", forward=["journal"]
        ),
    )
    journalvolume = django_filters.ModelChoiceFilter(
        queryset=JournalVolume.objects.all(),
        widget=autocomplete.ModelSelect2(
            url="journalvolumeautocomplete2", forward=["journalyear"]
        ),
    )

    class Meta:
        model = Article
        fields = {"journalyear", "journalvolume", "journal"}

urls.py

urlpatterns = [
    path("journals/", JournalListView.as_view(), name="journals"),
    path("journal/<str:slug>", JournalDetailView.as_view(), name="journal_detail"),
    # Django-autocomplete-light
    path(
        "journalyearautocomplete2/",
        JournalYearAutocomplete2.as_view(),
        name="journalyearautocomplete2",
    ),
    path(
        "journalvolumeautocomplete2/",
        JournalVolumeAutocomplete2.as_view(),
        name="journalvolumeautocomplete2",
    ),
    path(
        "journalautocomplete2/",
        JournalAutocomplete2.as_view(),
        name="journalautocomplete2",
    ),
]

编辑： 它对读者有效。

def article_list(request, slug):
    journal = get_object_or_404(Journal, slug=slug)
    my_filter_defaults = {'journal': journal}
    f = JournalFilter(request.GET or my_filter_defaults)
    return render(request, 'journals/journaldetail_list.html', {'filter': f, 'journal': journal})

Answer 1

Django-filter 绑定一个字典，通常是 request.GET 来过滤它的查询集。来自文档：

def product_list(request):
    f = ProductFilter(request.GET, queryset=Product.objects.all())
    return render(request, 'my_app/template.html', {'filter': f})

因此，如果您在未指定过滤的情况下需要默认值，您可以这样做

    my_filter_defaults = { ... }
    f = ProductFilter(request.GET or my_filter_defaults, queryset=Product.objects.all())

（Pythonic 用法：空字典是错误的，因此使用默认值代替）

您也可以修改 request.GET，但请注意它是 QueryDict 且不可变，因此您必须先复制它

my_dict = request.GET.copy( )

if not my_dict.get( 'foo', None):
    my_dict['foo'] = 'my_foo_default'
...
f = ProductFilter(my_dict, queryset=Product.objects.all())

我对 DAL 不熟悉。

Filter中添加动态初值

Add a dynamic initial value in Filter

django

django-filter

django-autocomplete-light