Django - form Clean() and field errors

Question

I'm trying to set field errors in a form clean() and I'm currently doing:

self._errors['address'] = self._errors.get('address', ErrorList())
self._errors['address'].append(_(u'Please specify an address.'))

Is there a better and if possible shorter method for doing this?

use self.errors instead, it returns _errors and is not meant to be private — radtek, Mar 24 '15 at 14:20

score 14 · Answer 1 · edited Jul 17 '18 at 11:28

14

New in Django 1.7 is Form.add_error( field, message ).

edited Jul 17 '18 at 11:28

guettli

answered Oct 28 '14 at 23:44

ManicDee

score 8 · Answer 2 · answered Mar 28 '13 at 09:58

Maybe this will help you . Its generally preferred you override clean and inside the function you could do the following

If you want to raise form specific errors you could do .

self._errors["field"] = ErrorList([u"Error"])

this is make sure you get the error class

if you have an non field error you could simple raise a validation error like so

raise forms.ValidationError(_("Error"))

Hope this helps.

Alexander Lebedev · Answer 3 · 2012-04-02T17:31:47.620

6

Standard way is raise ValidationError(message).
Move field-specific validation to clean_<fieldname>() methods, clean_address in your case. ValidationError raised in such method will attach error message to specific field. One raised from clean() will be attributed to model in general.

edited Apr 02 '12 at 17:31

answered Apr 01 '12 at 21:54

Alexander Lebedev

1

I'm currently using `clean()` for validating certain things related to multiple fields -- I'm quite new to Django and Python in general and I was wondering if there was better/shorter way for checking/creating/appending field specific errors. – RS7 Apr 01 '12 at 22:00
Added item #3, perhaps it describes what you need. Taken from django's internal implementation of `clean_fields` – Alexander Lebedev Apr 01 '12 at 22:11
Can you expand on your suggestion #3? It doesn't work for me. I can see that the [`ValidationError` class](https://code.djangoproject.com/browser/django/trunk/django/core/exceptions.py#L41) accepts a dictionary of errors like that, but [`Forms._clean_form`](https://code.djangoproject.com/browser/django/trunk/django/forms/forms.py#L297) doesn't actually make use of it. – Gareth Rees Apr 02 '12 at 11:21
@AlexLebedev - I haven't tested your third suggestion but according to the docs that would be incorrect, no? When setting field specific errors, one should assign messages to `self._errors`. – RS7 Apr 02 '12 at 15:48
You're right, I confused form and model validation. #3 will only work for models. – Alexander Lebedev Apr 02 '12 at 17:31

3 Answers3