模型形式的Django必填字段

Question

I have a form where a couple of fields are coming out as required when I don't want them too. Here is the form from models.py

class CircuitForm(ModelForm):
    class Meta:
        model = Circuit
        exclude = ('lastPaged',)
    def __init__(self, *args, **kwargs):
        super(CircuitForm, self).__init__(*args, **kwargs)
        self.fields['begin'].widget = widgets.AdminSplitDateTime()
        self.fields['end'].widget = widgets.AdminSplitDateTime()

In the actual Circuit model, the fields are defined like this:

begin = models.DateTimeField('Start Time', null=True, blank=True)
end = models.DateTimeField('Stop Time', null=True, blank=True)

My views.py for this is here:

def addCircuitForm(request):
    if request.method == 'POST':
        form = CircuitForm(request.POST)
        if form.is_valid():
            form.save()
            return HttpResponseRedirect('/sla/all')
    form = CircuitForm()    
    return render_to_response('sla/add.html', {'form': form})

What can I do so that the two fields aren't required?

Answer 1

If you don't want to modify blank setting for your fields inside models (doing so will break normal validation in admin site), you can do the following in your Form class:

def __init__(self, *args, **kwargs):
    super(CircuitForm, self).__init__(*args, **kwargs)

    for key in self.fields:
        self.fields[key].required = False 

The redefined constructor won't harm any functionality.

Answer 2

If the model field has blank=True, then required is set to False on the form field. Otherwise, required=True

Says so here: http://docs.djangoproject.com/en/dev/topics/forms/modelforms/

Looks like you are doing everything right. You could check the value of self.fields['end'].required .

Answer 3

Expanding on DataGreed's answer, I created a Mixin that allows you to specify a fields_required variable on the Meta class like this:

class MyForm(RequiredFieldsMixin, ModelForm):

    class Meta:
        model = MyModel
        fields = ['field1', 'field2']
        fields_required = ['field1']

Here it is:

class RequiredFieldsMixin():

    def __init__(self, *args, **kwargs):

        super().__init__(*args, **kwargs)

        fields_required = getattr(self.Meta, 'fields_required', None)

        if fields_required:
            for key in self.fields:
                if key not in fields_required:
                    self.fields[key].required = False

Answer 4

It's not an answer, but for anyone else who finds this via Google, one more bit of data: this is happening to me on a Model Form with a DateField. It has required set to False, the model has "null=True, blank=True" and the field in the form shows required=False if I look at it during the clean() method, but it's still saying I need a valid date format. I'm not using any special widget and I get the "Enter a valid date" message even when I explicitly set input_formats=['%Y-%m-%d', '%m/%d/%Y', '%m/%d/%y', ''] on the form field.

EDIT: Don't know if it'll help anyone else, but I solved the problem I was having. Our form has some default text in the field (in this case, the word "to" to indicate the field is the end date; the field is called "end_time"). I was specifically looking for the word "to" in the form's clean() method (I'd also tried the clean_end_time() method, but it never got called) and setting the value of the clean_data variable to None as suggested in this Django ticket . However, none of that mattered as (I guess) the model's validation had already puked on the invalid date format of "to" without giving me a chance to intercept it.

Answer 5

This is a bug when using the widgets:

workaround: Using Django time/date widgets in custom form

or ticket 12303

Answer 6

From the model field documentation ,

If you have a model as shown below,

class Article(models.Model):
    headline = models.CharField(
        max_length=200,
        null=True,
        blank=True,
        help_text='Use puns liberally',
    )
    content = models.TextField()

You can change the headline's form validation to required=True instead of blank=False as that of the model as defining the field as shown below.

class ArticleForm(ModelForm):
    headline = MyFormField(
        max_length=200,
        required=False,
        help_text='Use puns liberally',
    )

    class Meta:
        model = Article
        fields = ['headline', 'content']

So answering the question,

class CircuitForm(ModelForm):
    begin = forms.DateTimeField(required=False)
    end = forms.DateTimeField(required=False)
        class Meta:
            model = Circuit
            exclude = ('lastPaged',)

this makes begin and end to required=False