将会话数据传递到 ModelAdmin 内的 ModelForm

Question

我试图在实例方法中初始化 MyModelAdmin 类的表单属性，如下所示：

class MyModelAdmin(admin.ModelAdmin): 
    def queryset(self, request):
        MyModelAdmin.form = MyModelForm(request.user)

我的目标是根据当前会话自定义 MyModelForm 的编辑表单。然而，当我尝试这样做时，我不断收到错误（如下所示）。这是将会话数据传递给 ModelForm 的正确位置吗？如果是这样，那么可能是什么导致了这个错误？

TypeError at ...

异常类型：TypeError

异常值：issubclass() arg 1 必须是类

异常位置：/usr/lib/pymodules/python2.6/django/forms/models.py in 新，第 185 行

Answer 1

结合 Izz ad-Din Ruhulessin 的回答 和 Cikić Nenad 的建议，我最终得到了一个非常出色且简洁的解决方案，如下所示：

class CustomModelAdmin(admin.ModelAdmin):
    def get_form(self, request, obj=None, **kwargs):
        self.form.request = request #so we can filter based on logged in user for example
        return super(CustomModelAdmin, self).get_form(request,**kwargs)

然后只需为 modeladmin 设置一个自定义表单，例如：

form = CustomAdminForm

并在自定义 modelform 类访问请求中，例如：

self.request #对表单附属的请求做一些事情

Answer 2

理论上，您可以重写 ModelAdmin 的 get_form 方法：

# In django.contrib.admin.options.py
def get_form(self, request, obj=None, **kwargs):
    """
    Returns a Form class for use in the admin add view. This is used by
    add_view and change_view.
    """
    if self.declared_fieldsets:
        fields = flatten_fieldsets(self.declared_fieldsets)
    else:
        fields = None
    if self.exclude is None:
        exclude = []
    else:
        exclude = list(self.exclude)
    exclude.extend(kwargs.get("exclude", []))
    exclude.extend(self.get_readonly_fields(request, obj))
    # if exclude is an empty list we pass None to be consistant with the
    # default on modelform_factory
    exclude = exclude or None
    defaults = {
        "form": self.form,
        "fields": fields,
        "exclude": exclude,
        "formfield_callback": curry(self.formfield_for_dbfield, request=request),
    }
    defaults.update(kwargs)
    return modelform_factory(self.model, **defaults)

请注意，这会返回表单类而不是表单实例。

Answer 3

如果像我这样的新手经过这里：
我必须定义：

class XForm(forms.ModelForm):    
    request=None    

然后在上一篇文章的末尾

    mfc=modelform_factory(self.model, **defaults)   
    self.form.request=request   #THE IMPORTANT statement   
    return mfc

Answer 4

我使用查询集来过滤记录，也许这个例子可以帮助你：

.....
.....
def queryset(self, request):
    cuser = User.objects.get(username=request.user)

    qs = self.model._default_manager.get_query_set()
    ordering = self.ordering or () # otherwise we might try to *None, which is bad ;)

    if ordering:
        qs = qs.order_by(*ordering)

    qs = qs.filter(creator=cuser.id)

    return qs

Answer 5

这是 nemesisfixx 解决方案的生产/线程安全变体：

def get_form(self, request, obj=None, **kwargs):
    class NewForm(self.form):
        request = request
    return super(UserAdmin, self).get_form(request, form=NewForm, **kwargs)

Answer 6

class CustomModelAdmin(admin.ModelAdmin):

    def get_form(self, request, obj=None, **kwargs):
        get_form = super(CustomModelAdmin, self).get_form(request,**kwargs)
        get_form.form.request = request
        return get_form

现在在 ModelForm 中，我们可以通过

self.request

示例访问它：

class CustomModelForm(forms.ModelForm):

    def __init__(self, *args, **kwargs):
        super(TollConfigInlineForm, self).__init__(*args, **kwargs)
        request = self.request
        user = request.user