Django doesn't call model clean method

Question

I have a view, which creates models from CSV file. I've added clean method to the model class definition, but it isn't called when model is created.

Here is example of models.py:

class Run(models.Model):
    name = models.CharField(max_length=120)
    tested_build = models.ForeignKey('apps.Build')
    timestamp_start = models.DateTimeField()
    timestamp_end = models.DateTimeField()

class CommonMeasurement(models.Model):
    timestamp = models.DateTimeField()
    value = models.FloatField()
    run = models.ForeignKey(Run)

    def clean(self):
        super(CommonMeasurement, self).clean()
        print 'here we go'
        if self.timestamp < self.run.timestamp_start or self.timestamp > self.run.timestamp_end:
            raise django_excetions.ValidationError('Measurement is outside the run')


class ClientMeasurement(CommonMeasurement):
    metric = models.ForeignKey(ClientMetric)
    account = models.CharField(max_length=120, blank=True)

Here is my Form View code examples:

class BaseMeasurementsUpload(generic_views.FormView):
    template_name = 'upload.html'
    models_to_upload = None   

    def get_success_url(self):
        return self.request.get_full_path()

    def form_valid(self, form):
        uploader = getattr(importers, form.cleaned_data['uploader'])
        try:
            the_uploader = uploader(form.cleaned_data, self.models_to_upload)
            upload_results = the_uploader.get_result_info()
        except django_exceptions.ValidationError as e:
            custom_errors = e
        return render_to_response(self.template_name,
                                  {'upload_results': upload_results,
                                   'custom_errors': custom_errors},
                                  context_instance=RequestContext(self.request))


class ClientMeasurementsUploadView(BaseMeasurementsUpload):
    form_class = forms.ClientMeasurementsUploadForm
    models_to_upload = models.ClientMeasurement

    def get_form(self, form_class):
        uploaders = (('MeasurementsSimpleCsv', importers.MeasurementsSimpleCsv.__doc__),
                     ('ClientMeasurementsBulkCsv', importers.ClientMeasurementsBulkCsv.__doc__,))
        if self.request.POST:
            # get bound form
            return self.form_class(uploaders,
                                   self.request.POST,
                                   self.request.FILES)
        else:
            return forms.ClientMeasurementsUploadForm(uploaders)

importers perform actual validation and call create method for each model.

Can you post your view code? Perhaps you are not calling is_valid on your ModelForm? — Fiver
– Fiver, Commented Sep 14, 2013 at 15:35
clean is for ModelForm or Form objects. Not for models. this would never get called automatically. — karthikr
– karthikr, Commented Sep 14, 2013 at 15:58
@karthikr -- while you're correct that this clean() will not be called automatically, you're incorrect that it's "not for models" -- see the documentation on this point — Paul Bissex
– Paul Bissex, Commented Dec 21, 2018 at 3:08

Seenu S · Accepted Answer · 2017-10-11 14:46:09Z

55

To call the model clean method we will override save method. Check the link: https://docs.djangoproject.com/en/2.0/ref/models/instances/#django.db.models.Model.clean

class CommonMeasurement(models.Model):
    timestamp = models.DateTimeField()
    value = models.FloatField()
    run = models.ForeignKey(Run)

    def clean(self):
        if self.timestamp < self.run.timestamp_start or self.timestamp > self.run.timestamp_end:
            raise django_excetions.ValidationError('Measurement is outside the run')

    def save(self, *args, **kwargs):
        self.full_clean()
        return super(CommonMeasurement, self).save(*args, **kwargs)

edited Oct 11, 2017 at 14:46

answered Aug 27, 2015 at 14:22

Seenu S

3,5016 gold badges34 silver badges46 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

SirSaleh Over a year ago

Thanks. In djangorestframework, the clean method not calling which using this method my problem solved.

aviya.developer Over a year ago

@SirSaleh did you manage to get an error sent back to the REST api or did it just showed a debugger error?

Nikolai Golub · Accepted Answer · 2013-09-14 15:14:53Z

15

I've found a solution to override method:

class CommonMeasurement(models.Model):
    timestamp = models.DateTimeField()
    value = models.FloatField()
    run = models.ForeignKey(Run)

    objects = models.Manager()
    analyzes = managers.MeasureStatManager()

    def save(self, **kwargs):
        self.clean()
        return super(CommonMeasurement, self).save(**kwargs)

    def clean(self):
        super(CommonMeasurement, self).clean()
        print 'here we go'
        if self.timestamp < self.run.timestamp_start or self.timestamp > self.run.timestamp_end:
            raise django_excetions.ValidationError('Measurement is outside the run')

But I'm not sure that it can be a good decision.

answered Sep 14, 2013 at 15:14

Nikolai Golub

3,5864 gold badges37 silver badges61 bronze badges

6 Comments

Fiver Over a year ago

I believe calling clean from save will prevent your ValidationError from reaching your view/template, so the user would not see the error message but a debug message w/traceback if debug=True or a server error if debug is False.

Nikolai Golub Over a year ago

Actually, validation error is successfully passed to upper view layer.

John Pang Over a year ago

This works however Django doesn't like ValidationError during save() and return a (horrible) 500 Server Error instead of 400 Bad Request. I'm still looking for solution on this.

mhyousefi Over a year ago

I'm using Django==2.2.5 and djangorestframework==3.10.3 and this annoying 500 error is still happening! Any solutions?

Damir Nafikov Over a year ago

if there are people with problem of 500 debug message instead of with normal admin error message - in django==3.2 its better call ValidationError from django.core.exceptions.ValidationError

|

Thomas Maurin · Accepted Answer · 2014-11-26 23:09:30Z

8

Apparently model.clean() is never called to ensure backward compatibility. For more information on this: https://code.djangoproject.com/ticket/13100

answered Nov 26, 2014 at 23:09

Thomas Maurin

3674 silver badges9 bronze badges

2 Comments

Nikolai Golub Over a year ago

Is it bad practice to use my solution? Which compatibility I break with auto-calling clean() method from save?

Thomas Maurin Over a year ago

1. My solution was to move all the code I would have put in clean() in save(). In that respect I think your solution is cleaner. 2. I have no idea what it is supposed to break.

Ariel · Accepted Answer · 2019-01-28 08:46:31Z

3

Apparently in newer versions of Django the ModelForm.full_clean does call it's instance's full_clean method:

https://github.com/django/django/blob/14e2b1/django/forms/models.py#L403

edited Jan 28, 2019 at 8:46

answered Oct 1, 2015 at 12:58

Ariel

3,6516 gold badges45 silver badges64 bronze badges

3 Comments

Flimm Over a year ago

Yes, but save doesn't call full_clean either.

Adam Barnes Over a year ago

github.com/django/django/blob/… for a link that won't become confusingly invalid in future.

Ariel Over a year ago

Thanks @AdamBarnes, I've updated the link in the answer ;)

Collectives™ on Stack Overflow

Django doesn't call model clean method

4 Answers 4

2 Comments

6 Comments

2 Comments

3 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

2 Comments

6 Comments

2 Comments

3 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related