在保存之前修改内联formset

时间:2015-12-11 01:01:58

标签: django django-forms

tldr;我需要在验证和保存表单之前添加所需的“作者”字段。

有两种型号:DocumentsRevisions。每个Document都可以有多个Revisions,每个修订都可以作为作者(User对象)。当然我不希望用户能够自己设置作者ID,所以我需要自己设置。

在编辑页面上,用户可以修改文档标题并创建新修订。有两种形式:DocumentFormRevisionInlineFormset

在我们验证并保存所有内容之前,我似乎无法在RevisionInlineFormset方法中将作者分配给post

forms.py

class DocumentForm(forms.ModelForm):
    class Meta:
        fields = ['title', 'path']
        model = Document

RevisionInlineFormset = inlineformset_factory(
    Document,
    Revision,
    extra=1, max_num=1,
    fields=('content',),
    can_delete=False)

views.py

class DocUpdate(mixins.LoginRequiredMixin, generic.edit.UpdateView):

    """ Edit a document. """

    form_class = DocumentForm
    template_name = 'spaces/document/edit.html'

    def get_object(self):
        try:
            return Document.objects.get_by_path(self.kwargs["path"])
        except ObjectDoesNotExist:
            raise Http404

    def get(self, request, *args, **kwargs):
        """ Handles GET requests. """
        self.object = self.get_object()

        # Get latest revision
        rev_qs = self.object.revision_set.order_by('-created_on')
        if rev_qs.count():
            rev_qs = rev_qs.filter(pk=rev_qs[0].pk)

        form_class = self.get_form_class()
        form = self.get_form(form_class)
        revision_form = RevisionInlineFormset(
            instance=self.object,
            queryset=rev_qs)

        return self.render_to_response(
            self.get_context_data(form=form,
                                  revision_form=revision_form))

    def post(self, request, *args, **kwargs):
        """ Handles POST requests. """
        self.object = self.get_object()

        form_class = self.get_form_class()
        form = self.get_form(form_class)
        revision_form = RevisionInlineFormset(
            self.request.POST, instance=self.object)

        if (form.is_valid() and revision_form.is_valid()):
            return self.form_valid(form, revision_form)
        return self.form_invalid(form, revision_form)

    def form_valid(self, form, revision_form):
        """ All good. Finish up and save. """
        self.object = form.save()

        revision_form.instance = self.object
        revision_form.save()

        return HttpResponseRedirect(self.get_success_url())

1 个答案:

答案 0 :(得分:4)

我建议这样做:

<强> forms.py

from .models import Comment, Post
from django.forms.models import inlineformset_factory, ModelForm, BaseInlineFormSet


class PostCommentBaseFormset(BaseInlineFormSet):
    def __init__(self, *args, **kwargs):
        user = kwargs.pop('user', None)
        super(PostCommentBaseFormset, self).__init__(*args, **kwargs)
        if user:
            for form in self.forms:
                if form.instance.pk is None:
                    form.fields['user'].initial = user #or form.initial['user'] = user

CommentFormset = inlineformset_factory(Post, Comment, extra=3, exclude=[], formset=PostCommentBaseFormset)

<强> views.py

from .forms import CommentFormset

def post_create(request, *args, **kwargs):
    ...
    context['formset'] = CommentFormset(instance=post, user=request.user)
    ...

如果您想避免使用POST数据覆盖'user'字段,请从formset中排除'user'字段:

CommentFormset = inlineformset_factory(Post, Comment, extra=3, exclude=['user'], formset=PostCommentBaseFormset)

并像这样更改PostCommentBaseFormset:

class PostCommentBaseFormset(BaseInlineFormSet):
    def __init__(self, *args, **kwargs):
        user = kwargs.pop('user', None)
        super(PostCommentBaseFormset, self).__init__(*args, **kwargs)
        for form in self.forms:
            if form.instance.pk is None:
                form.instance.user = user 

还有其他方法可以实现您的目标(比如在保存formset之后迭代视图函数中的每个新实例,或者以formset的形式覆盖“clean”方法等等)但是在我看来它们更复杂