#16168 closed Cleanup/optimization (fixed)
Form validation is bypassed on Admin Inline ModelForms that define extra fields
| Reported by: | Owned by: | nobody | |
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| Component: | Documentation | Version: | dev |
| Severity: | Normal | Keywords: | validation, modelforms |
| Cc: | Triage Stage: | Accepted | |
| Has patch: | yes | Needs documentation: | no |
| Needs tests: | no | Patch needs improvement: | no |
| Easy pickings: | yes | UI/UX: | no |
Description
When defining extra/overridden fields on modelforms, validation is bypassed. This can lead to errors under some circumstances.
For example, you have a model 'Book' that defines a ForeignKey to 'Author' named 'author'. On your ModelForm you replace this field by a CharField (or some other type) for whatever reason.
On submitting an invalid form, a ValueError will be raised complaining that the datatype is incorrect.
My proposed solution is overriding ModelForm._post_clean():
class ModelForm(BaseModelForm): def _post_clean(self): if len(self._errors) == 0: super(ModelForm, self)._post_clean()
Attachments (2)
Change History (10)
comment:1 by , 13 years ago
| Component: | Forms → Documentation |
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| Needs documentation: | set |
| Triage Stage: | Unreviewed → Accepted |
| Type: | Bug → Cleanup/optimization |
| Version: | 1.2 → SVN |
comment:2 by , 13 years ago
| UI/UX: | unset |
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DjangoCon Europe 2011 sprint: commenced work on this ticket
comment:3 by , 13 years ago
I have attached a diff with (I hope) the requested documentation changes.
comment:4 by , 13 years ago
| Has patch: | set |
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comment:5 by , 13 years ago
| Patch needs improvement: | set |
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Looks okay to me, but it needs appropriate rst markup (backticks around ValueError is all that I see missing.)
by , 13 years ago
| Attachment: | 16168_v2.diff added |
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comment:6 by , 13 years ago
| Needs documentation: | unset |
|---|---|
| Patch needs improvement: | unset |
I added backticks around ValueError in PieterSwinkels patch.
comment:7 by , 12 years ago
| Resolution: | → fixed |
|---|---|
| Status: | new → closed |
This does happen in svn as well. However, the problem is not that validation is being bypassed; because of the invalid input type from the form field, the attempt to construct an instance fails loudly. There is no way to get around this cleanly - it's a programming error, not a problem with django. The most we could do would be to add a note to the docs about the dangers of not mimicking data type conversion when overriding fields.