[Django] #20347: Creating a formset with more than max_num forms
Django
-------------------------------+--------------------
Reporter: CarstenF | Owner: nobody
Type: Uncategorized | Status: new
Component: Forms | Version: 1.5
Severity: Normal | Keywords:
Triage Stage: Unreviewed | Has patch: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------+--------------------
The documentation at
https://docs.djangoproject.com/en/1.5/topics/forms/formsets/#limiting-the-
maximum-number-of-forms seems to indicate (if I understood it correctly)
that the purpose of the `max_num` parameter is to prevent that someone
sends a manipulated, excessively large value in the hidden form field that
states the number of (extra) forms that are submitted, whereas it is not
(directly) related to the number of forms that are //actually// POSTed, or
initialized via parameter `initials`.
However, following the example at that page, with `MyInitials` being a
list of e.g. 1500 initial values and `request.POST` containing more than
1500 formsets:
{{{
#!python
>>> ArticleFormSet = formset_factory(ArticleForm, extra=0)
>>> formset1 = ArticleFormSet(initial=MyInitials)
>>> formset2 = ArticleFormSet(request.POST)
}}}
Now, accessing `formset1.forms[1000]` throws an IndexError exception.
The `max_num` is at its default value of 1000, but in the above context,
it is not expected that `formset1` or `formset2` is reduced to `max_num`
forms -- I'd have expected each to have the full number of forms as
initialized.
Related thread at django-users:
http://thread.gmane.org/gmane.comp.python.django.user/152946
--
Ticket URL: <https://code.djangoproject.com/ticket/20347>
Django <https://code.djangoproject.com/>
The Web framework for perfectionists with deadlines.
Django
--------------------------------------+------------------------------------
Reporter: CarstenF | Owner: nobody
Type: Cleanup/optimization | Status: new
Component: Documentation | Version: 1.5
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 1 | UI/UX: 0
--------------------------------------+------------------------------------
Changes (by timo):
* needs_better_patch: => 0
* component: Forms => Documentation
* needs_tests: => 0
* easy: 0 => 1
* needs_docs: => 0
* type: Uncategorized => Cleanup/optimization
* stage: Unreviewed => Accepted
Comment:
I believe the code is working as intended, accepting as a documentation
clarification.
--
Ticket URL: <https://code.djangoproject.com/ticket/20347#comment:1>
Django
--------------------------------------+------------------------------------
Type: Cleanup/optimization | Status: new
Component: Documentation | Version: 1.5
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 1 | UI/UX: 0
--------------------------------------+------------------------------------
Comment (by anonymous):
Clarifying the documentation would certainly help, but doesn't this mean
that we have to use `max_num=len(MyInitials)` as a "permanent" work-around
in user code?
{{{
#!python
ArticleFormSet = formset_factory(ArticleForm, max_num=len(MyInitials),
extra=0)
}}}
--
Ticket URL: <https://code.djangoproject.com/ticket/20347#comment:2>
Django
--------------------------------------+------------------------------------
Type: Cleanup/optimization | Status: new
Component: Documentation | Version: 1.5
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 1 | UI/UX: 0
--------------------------------------+------------------------------------
Comment (by CarstenF):
(Sorry, the above comment was by me, but I realized too late that I wasn't
logged in when submitting.)
--
Ticket URL: <https://code.djangoproject.com/ticket/20347#comment:3>
Django
Reporter: CarstenF | Owner: nobody
Type: Bug | Status: new
Component: Forms | Version: 1.5
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 1 | UI/UX: 0
Changes (by carljm):
* type: Cleanup/optimization => Bug
* component: Documentation => Forms
Comment:
Yes, this is actually a bug, and it is already fixed in master as part of
the fix for #20084. `absolute_max`, which unlike `max_num` is a hard limit
on the number of forms instantiated, in Django 1.5.1 is set to `max(1000,
max_num)`, which means that if `max_num >= 1000`, then `absolute_max ==
max_num`, meaning `max_num` essentially becomes a hard limit (which it is
not intended or documented to be).
Even with the fix for #20084, where `absolute_max` is set to `max_num +
1000` instead, it would still be possible for someone to hit this issue if
they instantiate a formset with over 1000 more initial forms than
`max_num`. Given that it seems people are using formsets with higher
numbers of forms than anticipated, I think we should probably go further
than #20084 did and fix this fully, by documenting `absolute_max` and
making it explicitly configurable in `formset_factory`.
The other question is whether this deserves a backport to 1.5.X. I think
it probably does, given that it could be a data-loss situation.
--
Ticket URL: <https://code.djangoproject.com/ticket/20347#comment:4>
Django
Reporter: CarstenF | Owner: ethurgood
Type: Bug | Status: assigned
Component: Forms | Version: 1.5
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 1 | UI/UX: 0
Changes (by ethurgood):
* status: new => assigned
* owner: nobody => ethurgood
--
Ticket URL: <https://code.djangoproject.com/ticket/20347#comment:5>
Django
-----------------------------+-------------------------------------
Reporter: CarstenF | Owner: ethurgood
Type: New feature | Status: assigned
Component: Forms | Version: 1.5
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Needs tests: 0 | Patch needs improvement: 1
Easy pickings: 0 | UI/UX: 0
Changes (by timo):
* needs_better_patch: 0 => 1
* has_patch: 0 => 1
* type: Bug => New feature
* easy: 1 => 0
Comment:
[https://github.com/django/django/pull/1593 Pull request] which has some
minor comments from Carl.
--
Ticket URL: <https://code.djangoproject.com/ticket/20347#comment:6>
Django
Reporter: Carsten Fuchs | Owner: David Smith
Type: New feature | Status: assigned
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Has patch: 1 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Changes (by David Smith):
* owner: ethurgood => David Smith
* needs_better_patch: 1 => 0
--
Ticket URL: <https://code.djangoproject.com/ticket/20347#comment:7>
Django
-------------------------------+---------------------------------------
Reporter: Carsten Fuchs | Owner: David Smith
Type: New feature | Status: assigned
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Has patch: 1 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Changes (by felixxm):
* version: 1.5 => master
Comment:
[https://github.com/django/django/pull/12830 PR]
--
Ticket URL: <https://code.djangoproject.com/ticket/20347#comment:8>
Django
-------------------------------+---------------------------------------
Reporter: Carsten Fuchs | Owner: David Smith
Type: New feature | Status: assigned
Component: Forms | Version: master
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Has patch: 1 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Changes (by felixxm):
* needs_better_patch: 0 => 1
--
Ticket URL: <https://code.djangoproject.com/ticket/20347#comment:9>
Django
-------------------------------+---------------------------------------
Reporter: Carsten Fuchs | Owner: David Smith
Type: New feature | Status: assigned
Component: Forms | Version: master
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Has patch: 1 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Changes (by David Smith):
* needs_better_patch: 1 => 0
--
Ticket URL: <https://code.djangoproject.com/ticket/20347#comment:10>
Django
Reporter: Carsten Fuchs | Owner: David
| Smith
Type: New feature | Status: assigned
Component: Forms | Version: master
Severity: Normal | Resolution:
| checkin
Has patch: 1 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Changes (by felixxm):
* stage: Accepted => Ready for checkin
--
Ticket URL: <https://code.djangoproject.com/ticket/20347#comment:11>
Django
-------------------------------------+-------------------------------------
Reporter: Carsten Fuchs | Owner: David
| Smith
Type: New feature | Status: assigned
Component: Forms | Version: master
Severity: Normal | Resolution:
Keywords: | Triage Stage: Ready for
| checkin
Has patch: 1 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Comment (by Mariusz Felisiak <felisiak.mariusz@…>):
In [changeset:"b5aa9cb20f2d8fbffec3bc18aa31fca5f26d6f64" b5aa9cb2]:
{{{
#!CommitTicketReference repository=""
revision="b5aa9cb20f2d8fbffec3bc18aa31fca5f26d6f64"
Refs #20347 -- Added test for formset_factory()'s absolute_max default.
Co-authored-by: ethurgood <ethu...@gmail.com>
}}}
--
Ticket URL: <https://code.djangoproject.com/ticket/20347#comment:12>
Django
-------------------------------------+-------------------------------------
Reporter: Carsten Fuchs | Owner: David
| Smith
Component: Forms | Version: master
Severity: Normal | Resolution: fixed
Keywords: | Triage Stage: Ready for
| checkin
Has patch: 1 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Changes (by Mariusz Felisiak <felisiak.mariusz@…>):
* status: assigned => closed
* resolution: => fixed
Comment:
In [changeset:"433dd737f94b09043f64b873b0ac067b3f97364b" 433dd73]:
{{{
#!CommitTicketReference repository=""
revision="433dd737f94b09043f64b873b0ac067b3f97364b"
Fixed #20347 -- Allowed customizing the maximum number of instantiated
forms in formsets.
Co-authored-by: ethurgood <ethu...@gmail.com>
}}}
--
Ticket URL: <https://code.djangoproject.com/ticket/20347#comment:13>
Django
-------------------------------------+-------------------------------------
Reporter: Carsten Fuchs | Owner: David
| Smith
Type: New feature | Status: closed
Component: Forms | Version: master
Severity: Normal | Resolution: fixed
Keywords: | Triage Stage: Ready for
| checkin
Has patch: 1 | Needs documentation: 0
Easy pickings: 0 | UI/UX: 0
Comment (by Mariusz Felisiak <felisiak.mariusz@…>):
In [changeset:"3254991762b49cfbeb8434842c19bbbad87cd9c6" 3254991]:
{{{
#!CommitTicketReference repository=""
revision="3254991762b49cfbeb8434842c19bbbad87cd9c6"
Refs #20347 -- Allowed customizing the maximum number of instantiated
forms in generic_inlineformset_factory().
Follow up to 433dd737f94b09043f64b873b0ac067b3f97364b.
}}}
--
Ticket URL: <https://code.djangoproject.com/ticket/20347#comment:14>