I want to override the bahaviour of saveas button - i need after pushing it to redirecrt me not in list of objects, but in a new object directly.
So i need to override the standart save method of ModelForm and get in there the request object - to check if saveas button was pressed:
*admin.py
class AirplanesAdmin(admin.ModelAdmin):
form = AirplaneEditForm
forms.py
class AirplaneEditForm(forms.ModelForm):
def __init__(self, *args, **kwargs):
self.request = kwargs.pop('request', None)
super(AirplaneEditForm, self).__init__(*args, **kwargs)
def clean(self):
print self.request
return self.cleaned_data
def save(self, force_insert=False, force_update=False, commit=True,):
plane = super(AirplaneEditForm, self).save(commit=False)
print self.request
if commit:
plane.save()
return plane
class Meta:
model = Airplanes
But in both prints request is None... Did I do something wrong ?
Django forms are something between models and views, which means they are context-agnostic. You generally should not do things that depend on request objects inside your form.
What #Rohan means is that AirplanesAdmin does not pass in request objects when your form is initialized, so when you kwargs.pop('request', None) the is actually an internal KeyError and the default value (the second argument, None) is returned. Nothing is really popped from kwargs. To override this behavior, you will need to override rendering methods of ModelAdmin.
Read the doc for methods you can use.
Request object is not being passed to forms.py from admin.py
So, in admin.py:
class AirplanesAdmin(admin.ModelAdmin):
form = AirplaneEditForm(request=request)
See another example here
Related
I created the FormView below that will dynamically return a form class based on what step in the process that the user is in. I'm having trouble with the get_form method. It returns the correct form class in a get request, but the post request isn't working.
tournament_form_dict = {
'1':TournamentCreationForm,
'2':TournamentDateForm,
'3':TournamentTimeForm,
'4':TournamentLocationForm,
'5':TournamentRestrictionForm,
'6':TournamentSectionForm,
'7':TournamentSectionRestrictionForm,
'8':TournamentSectionRoundForm,}
class CreateTournament(FormView):
template_name = 'events/create_tournament_step.html'
def __init__(self, *args, **kwargs):
form_class = self.get_form()
success_url = self.get_success_url()
super(CreateTournament, self).__init__(*args, **kwargs)
def get_form(self, **kwargs):
if 'step' not in kwargs:
step = '1'
else:
step = kwargs['step']
return tournament_form_dict[step]
def get_success_url(self, **kwargs):
if 'step' not in kwargs:
step = 1
else:
step = int(kwargs['step'])
step += 1
if 'record_id' not in kwargs:
record_id = 0
else:
record_id = int(kwargs['record_id'])
return 'events/tournaments/create/%d/%d/' % (record_id, step)
The post request fails at the django\views\generic\edit.py at the get_form line, which I realize is because I've overwritten it in my FormView:
def post(self, request, *args, **kwargs):
"""
Handle POST requests: instantiate a form instance with the passed
POST variables and then check if it's valid.
"""
form = self.get_form()
if form.is_valid(): …
return self.form_valid(form)
else:
return self.form_invalid(form)
However, when I change the name of my custom get_form method to say gen_form, like so:
def __init__(self, *args, **kwargs):
form_class = self.gen_form()
success_url = self.get_success_url()
super(CreateTournament, self).__init__(*args, **kwargs)
def gen_form(self, **kwargs):
if 'step' not in kwargs:
step = '1'
else:
step = kwargs['step']
return tournament_form_dict[step]
my form class doesn't get processed in the get request and evaluates to None. I'm scratching my head as to why when I override the get_form method, it works, but my own named method doesn't? Does anyone know what the flaw might be?
Django's FormMixin [Django-doc] defines a get_form function [Django-doc]. You here thus basically subclassed the FormView and "patched" the get_form method.
Your attempt with the gen_form does not work, since you only defined local variables, and thus do not make much difference anyway, only the super(..) call will have some side effects. The other commands will keep the CPU busy for some time, but at the end, will only assign a reference to a Form calls to the form_class variable, but since it is local, you will throw it away.
That being said, your function contains some errors. For example the **kwargs will usually contain at most one parameter: form_class. So the steps will not do much. You can access the URL parameters through self.args and self.kwargs, and the querystring parameters through self.request.GET. Furthermore you probably want to patch the get_form_class function anyway, since you return a reference to a class, not, as far as I understand it, a reference to an initilized form.
Constructing URLs through string processing is probably not a good idea either, since if you would (slightly) change the URL pattern, then it is likely you will forget to replace the success_url, and hence you will refer to a path that no longer exists. Using the reverse function is a safer way, since you pass the name of the view, and parameters, and then this function will "calculate" the correct URL. This is basically the mechanism behind the {% url ... %} template tag in Django templates.
A better approach is thus:
from django.urls import reverse
class CreateTournament(FormView):
template_name = 'events/create_tournament_step.html'
def get_form_class(self):
return tournament_form_dict[self.kwargs.get('step', '1')]
def get_success_url(self):
new_step = int(self.kwargs.get('step', 1)) + 1
# use a reverse
return reverse('name_of_view', kwargs={'step': new_step})
Have an admin form with overrided save method:
*models.py
class Banners(models.Model):
<...>
pages = models.ManyToManyField(Page, verbose_name='Pages', blank=True)
*forms.py
class BannerAdminForm(forms.ModelForm):
def __init__(self, *args, **kwargs):
super(BannerAdminForm, self).__init__(*args, **kwargs)
self.fields['pages'].queryset = Page.objects.filter(publisher_is_draft=1)
def save(self, force_insert=False, force_update=False, commit=True, *args, **kwargs):
banner = super(BannerAdminForm, self).save(commit=False, *args, **kwargs)
for c in banner.pages.all():
print c
if commit:
banner.save()
return banner
class Meta:
model = Banners
I overrided save() method because i want to intercept pages that will be added to banners, and add some extra pages depending of what pages was chosen by user. So I need to catch what pages object was chosen... But code for c in banner.pages.all(): returns me the already existed pages in banner, not the new ones.
If there some way to catch new values before i will save() the form ?
And the second question - if comes some new pages and deleted some old ones at the same time... is there will be the same mechanism to catch all that data ?
You should be able to get the pages selected from the form's cleaned_data.
self.cleaned_data['pages']
I have a Person model, which has a ForeignKey field to itself, called mother.
When the user goes to the 'add' admin form, I want to define an initial value for mother, in case there is a GET('mother') parameter, or leave it blank, in case there is not.
I have actually 2 questions:
How to access request inside ModelAdmin?
How to define initial value for a ForeignKey field?
In models.py:
class Person(models.Model):
name=models.CharField()
mother=models.ForeignKey('self')
In admin.py:
class PersonAdminForm(forms.ModelForm):
class Meta:
model = Person
class PersonAdmin(admin.ModelAdmin):
mother = request.GET.get('mother','') #don`t know how to access request
if mother != '':
form = PersonAdminForm
form.initial={'mother':Person.objects.get(id=mother)}
Well, this ain't working. Even if I only try to define a hardcoded initial value, it doesn`t work.
What am I doing wrong?
PS.: Of course, I may be asking the wrong questions, so I appreciate any help that solves the problem.
My solution:
class PersonAdmin(admin.ModelAdmin):
form = PersonAdminForm
# ...
def get_form(self, request, obj=None, *args, **kwargs):
form = super(PersonAdmin, self).get_form(request, *args, **kwargs)
# Initial values
form.base_fields['mother'].initial = None
if obj and obj.mother:
form.base_fields['mother'].initial = obj.mother
return form
Oh, it happens to be a lot easier than I thought.
If you pass a GET parameter with the name of the field as key to a Django`s add form, the GET parameters value will be set as initial value for that field.
In my case, I just needed to redirect to
localhost/admin/my_app/person/add/?&mother=< id >
There was no need for manipulating admin or anything.
Try overriding the get_form() method on ModelAdmin:
class PersonAdmin(admin.ModelAdmin):
form = PersonAdminForm
def get_form(self, request, *args, **kwargs):
form = super(PersonAdmin, self).get_form(request, *args, **kwargs)
mother = request.GET.get('mother', None)
if mother:
form.initial = {'mother': Person.objects.get(id=mother)}
return form
How can I set an initial value of a field in the automatically generated form for adding a Django model instance, before the form is displayed? I am using Django 1.3.1.
My model is the following:
class Foo(models.Model):
title = models.CharField(max_length=50)
description = models.TextField()
and the current admin form is really nothing special
class FooAdmin(admin.ModelAdmin):
ordering = ('title',)
When I use the admin page to add a new instance of Foo, I get a nice form with empty fields for title and description. What I would like is that the description field is set with a template that I obtain by calling a function.
My current best attempt at getting there is this:
def get_default_content():
return 'this is a template for a Foo description'
class FooAdminForm(django.forms.ModelForm):
class Meta:
model = Foo
def __init__(self, *args, **kwargs):
kwargs['initial'].update({'description': get_default_content()})
super(FooAdminForm, self).__init__(self, *args, **kwargs)
class FooAdmin(admin.ModelAdmin):
ordering = ('title',)
form = FooAdminForm
but if I try this I get this Django error:
AttributeError at /admin/bar/foo/add/
'FooForm' object has no attribute 'get'
Request Method: GET
Request URL: http://localhost:8000/admin/bar/foo/add/
Django Version: 1.3.1
Exception Type: AttributeError
Exception Value: 'FooForm' object has no attribute 'get'
Exception Location: /www/django-site/venv/lib/python2.6/site-packages/django/forms/widgets.py in value_from_datadict, line 178
I don't know what is wrong here, and what I should do to make it work. What I also find strange about this error (apart from the fact that I see it at all) is that there is no FooForm in my code at all?
Alasdair's approach is nice but outdated. Radev's approach looks quite nice and as mentioned in the comment, it strikes me that there is nothing about this in the documentation.
Apart from those, since Django 1.7 there is a function get_changeform_initial_data in ModelAdmin that sets initial form values:
def get_changeform_initial_data(self, request):
return {'name': 'custom_initial_value'}
You need to include self as the first argument in your __init__ method definition, but should not include it when you call the superclass' method.
def __init__(self, *args, **kwargs):
# We can't assume that kwargs['initial'] exists!
if 'initial' not in kwargs:
kwargs['initial'] = {}
kwargs['initial'].update({'description': get_default_content()})
super(FooAdminForm, self).__init__(*args, **kwargs)
Having said that, a model field can take a callable for its default, so you may not have to define a custom admin form at all.
class Foo(models.Model):
title = models.CharField(max_length=50)
description = models.TextField(default=get_default_content)
More then 3 years later,
But actually what you should do is override admin.ModelAdmin formfield_for_dbfield .. like this:
class FooAdmin(admin.ModelAdmin):
def formfield_for_dbfield(self, db_field, **kwargs):
field = super(FooAdmin, self).formfield_for_dbfield(db_field, **kwargs)
if db_field.name == 'description':
field.initial = 'My initial description'
elif db_field.name == 'counter':
field.initial = get_counter() + 1
return field
Cheers;
When adding new objects, it is convenient to use get_changeform_initial_data() as suggested by Wtower.
However, when changing existing objects, that does not work (see source).
In that case, you could extend ModelAdmin.get_form() as follows (using the OP's example):
def get_form(self, request, obj=None, change=False, **kwargs):
if obj and not obj.description:
obj.description = get_default_content()
return super().get_form(request, obj, change, **kwargs)
I've just created a forms.models.BaseInlineFormSet to override the default formset for a TabularInline model. I need to evaluate the user's group in formset validation (clean) because some groups must write a number inside a range (0,20).
I'm using django admin to autogenerate the interface.
I've tried getting the request and the user from the kwargs in the init method, but I couldn't get the reference.
This is what I have now:
class OrderInlineFormset(forms.models.BaseInlineFormSet):
def __init__(self, *args, **kwargs):
self.user = kwargs.pop('user')
super(OrderInlineFormset, self).__init__(*args, **kwargs)
def clean(self):
# get forms that actually have valid data
count = 0
for form in self.forms:
try:
if form.cleaned_data:
count += 1
if self.user.groups.filter(name='Seller').count() == 1:
if form.cleaned_data['discount'] > 20:
raise forms.ValidationError('Not authorized to specify a discount greater than 20%')
except AttributeError:
# annoyingly, if a subform is invalid Django explicity raises
# an AttributeError for cleaned_data
pass
if count < 1:
raise forms.ValidationError('You need to specify at least one item')
class OrderItemInline(admin.TabularInline):
model = OrderItem
formset = OrderInlineFormset
Then I use it as inlines = [OrderItemInline,] in my ModelAdmin.
Unfortunatly self.user is always None so I cannot compare the user group and the filter is not applied. I need to filter it because other groups should be able to specify any discount percent.
How can I do? If you also need the ModelAdmin code I'll publish it (I just avoided to copy the whole code to avoid confusions).
Well, I recognise my code there in your question, so I guess I'd better try and answer it. But I would say first of all that that snippet is really only for validating a minimum number of forms within the formset. Your use case is different - you want to check something within each form. That should be done with validation at the level of the form, not the formset.
That said, the trouble is not actually with the code you've posted, but with the fact that that's only part of it. Obviously, if you want to get the user from the kwargs when the form or formset is initialized, you need to ensure that the user is actually passed into that initialization - which it isn't, by default.
Unfortunately, Django's admin doesn't really give you a proper hook to intercept the initialization itself. But you can cheat by overriding the get_form function and using functools.partial to wrap the form class with the request argument (this code is reasonably untested, but should work):
from functools import partial
class OrderForm(forms.ModelForm):
def __init__(self, *args, **kwargs):
self.user = kwargs.pop('user')
super(OrderForm, self).__init__(*args, **kwargs)
def clean(self)
if self.user.groups.filter(name='Seller').count() == 1:
if self.cleaned_data['discount'] > 20:
raise forms.ValidationError('Not authorized to specify a discount greater than 20%')
return self.cleaned_data
class MyAdmin(admin.ModelAdmin):
form = OrderForm
def get_form(self, request, obj=None, **kwargs):
form_class = super(MyAdmin, self).get_form(request, obj, **kwargs)
return functools.partial(form_class, user=request.user)
Here's another option without using partials. First override the get_formset method in your TabularInline class.
Assign request.user or what ever extra varaibles you need to be available in the formset as in example below:
class OrderItemInline(admin.TabularInline):
model = OrderItem
formset = OrderInlineFormset
def get_formset(self, request, obj=None, **kwargs):
formset = super(OrderProductsInline, self).get_formset(request, obj, **kwargs)
formset.user = request.user
return formset
Now the user is available in the formset as self.user
class OrderInlineFormset(forms.models.BaseInlineFormSet):
def clean(self):
print(self.user) # is available here