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I need to generate Django forms.Form object with fields not from Model.fields (Database Table Columns names), but by records in Model.Table.
I have table Model in models.py:
class MntClasses(models.Model):
type = models.CharField(max_length=2, blank=True, null=True)
class_subtype = models.CharField(max_length=45, blank=True, null=True)
text = models.CharField(max_length=45, blank=True, null=True)
explanation = models.CharField(max_length=45, blank=True, null=True)
name = models.CharField(max_length=45, blank=True, null=True)
views.py
# Form generate
class Form_classes(forms.Form):
def __int__(self, *args, **kwargs,):
super(Form_classes, self).__init__(*args, **kwargs)
print("some")
for fld_ in args:
self.fields[fld_.name] = forms.BooleanField(label=fld_.text)
#Main
def page_Category_Main(request, post):
db_table = MntClasses
form_fld = db_table.objects.all()
'''
This QuerySet 20 records returned of <MntClasses: MntClasses object (0-19)> type.
QuerySet Filds Names: 'name','type','expalnation', 'text'
''':
form_ = Form_classes(*form_fld)
exit_ = {
'form': form_,
}
return render(request, template_name="category.html", context=exit_)
It raise TypeError
init() takes from 1 to 12 positional arguments but 20 were given
So, i have no idea what does it mean this code taken from were: Auto-generate form fields for a Form in django:
def __int__(self, *args, **kwargs,):
super(Form_classes, self).__init__(*args, **kwargs)
What is this "*args", how to use it?
How can I generate Form.fields by QuerySet form_fld.name in that case?
About args
To understand what args is you can take a look at this post which will eventually direct you to https://docs.python.org/3/tutorial/controlflow.html#arbitrary-argument-lists.
Basically it's a special python syntax which allows a function to retrieve multiple arguments as a tuple in a single variable.
About Django's Models
Do you really want to generate multiple forms?
If this is the case you would need to loop over your table:
forms = []
db_table = MntClasses
for item in db_table.objects.all():
forms.append(Form_classes(item))
exit_ = {
'form': forms,
}
the trick is then how you deal with the multiple forms on the front end.
Also you probably want to switch to a ModelForm which would look something like:
from django import forms
from myapp.models import MntClasses
class FormMnt(forms.ModelForm):
class Meta:
model = MntClasses
...
In case you want to handle multiple instances of MntClasses in a single form, you should look at Django's formsets.
taking my initial lessons with django ModelForm ,I wanted to give the user ,ability to edit an entry in a blog.The BlogEntry has a date,postedTime, title and content.I want to show the user an editform which shows all these fields,but with only title and content as editable. The date and postedTime should be shown as uneditable.
class BlogEntry(models.Model):
title = models.CharField(unique=True,max_length=50)
description = models.TextField(blank=True)
date = models.DateField(default=datetime.date.today)
postedTime = models.TimeField(null=True)
...
For adding an entry ,I use a ModelForm in the normal way..
class BlogEntryAddForm(ModelForm):
class Meta:
model = BlogEntry
...
But how do I create the edit form?I want it to show the date,postedTime as uneditable (but still show them on the form) and let the user edit the title and description.
if I use,exclude in class Meta for date and postedTime,that will cause them not to appear on the form.So,how can I show them as uneditable?
class BlogEntryEditForm(ModelForm):
class Meta:
model = BlogEntry
...?...
In the form object, declare the attribute of the field as readonly:
form.fields['field'].widget.attrs['readonly'] = True
Is date field represent a date when the entry first created or when it was modified last time? If first then use auto_now_add option else use auto_now. That is:
date = models.DateField(auto_now_add=True)
will set date to now when entry will be created.
auto_now_add makes field uneditable. For other cases use editable option to make any field uneditable. For example
postedDate = models.TimeField(null=True, editable=False)
Also, likely you will add posted boolean field to Entry model, so it is convinient to set auto_now on postedDate. It will set postedDate to now every time you modify a Entry including one when you set posted to True.
I implemented it this way: https://djangosnippets.org/snippets/10514/
this implementation uses the data of model instance for all read-only fields and not the data obtained while processing the form
below the same code but using his example
from __future__ import unicode_literals
from django.utils import six
from django.utils.encoding import force_str
__all__ = (
'ReadOnlyFieldsMixin',
'new_readonly_form_class'
)
class ReadOnlyFieldsMixin(object):
"""Usage:
class MyFormAllFieldsReadOnly(ReadOnlyFieldsMixin, forms.Form):
...
class MyFormSelectedFieldsReadOnly(ReadOnlyFieldsMixin, forms.Form):
readonly_fields = ('field1', 'field2')
...
"""
readonly_fields = ()
def __init__(self, *args, **kwargs):
super(ReadOnlyFieldsMixin, self).__init__(*args, **kwargs)
self.define_readonly_fields(self.fields)
def clean(self):
cleaned_data = super(ReadOnlyFieldsMixin, self).clean()
for field_name, field in six.iteritems(self.fields):
if self._must_be_readonly(field_name):
cleaned_data[field_name] = getattr(self.instance, field_name)
return cleaned_data
def define_readonly_fields(self, field_list):
fields = [field for field_name, field in six.iteritems(field_list)
if self._must_be_readonly(field_name)]
map(lambda field: self._set_readonly(field), fields)
def _all_fields(self):
return not bool(self.readonly_fields)
def _set_readonly(self, field):
field.widget.attrs['disabled'] = 'true'
field.required = False
def _must_be_readonly(self, field_name):
return field_name in self.readonly_fields or self._all_fields()
def new_readonly_form_class(form_class, readonly_fields=()):
name = force_str("ReadOnly{}".format(form_class.__name__))
class_fields = {'readonly_fields': readonly_fields}
return type(name, (ReadOnlyFieldsMixin, form_class), class_fields)
Usage:
class BlogEntry(models.Model):
title = models.CharField(unique=True,max_length=50)
description = models.TextField(blank=True)
date = models.DateField(default=datetime.date.today)
postedTime = models.TimeField(null=True)
# all fields are readonly
class BlogEntryReadOnlyForm(ReadOnlyFieldsMixin, forms.ModelForm):
class Meta:
model = BlogEntry
# selected fields are readonly
class BlogEntryReadOnlyForm2(ReadOnlyFieldsMixin, forms.ModelForm):
readonly_fields = ('date', 'postedTime')
class Meta:
model = BlogEntry
or use the function
class BlogEntryForm(forms.ModelForm):
class Meta:
model = BlogEntry
BlogEntryFormReadOnlyForm = new_readonly_form_class(BlogEntryForm, readonly_fields=('description', ))
This will prevent any user from hacking the request:
self.fields['is_admin'].disabled = True
Custom form example:
class MemberShipInlineForm(forms.ModelForm):
is_admin = forms.BooleanField(required=False)
def __init__(self, *args, **kwargs):
super(MemberShipInlineForm, self).__init__(*args, **kwargs)
if 'instance' in kwargs and kwargs['instance'].is_group_creator:
self.fields['is_admin'].disabled = True
class Meta:
model = MemberShip
fields = '__all__'
From the documentation,
class BlogEntryEditForm(ModelForm):
class Meta:
model = BlogEntry
readonly_fields = ['date','postedTime']
I have a model like this:
class MyModel(models.Model):
REGULAR = 1
PREMIUM = 2
STATUS_CHOICES = ((REGULAR, "regular"), (PREMIUM, "premium"))
name = models.CharField(max_length=30)
status = models.IntegerField(choices = STATUS_CHOICES, default = REGULAR)
class MyForm(forms.ModelForm):
class Meta:
model = models.MyModel
In a view I initialize one field and try to make it non-editable:
myform = MyForm(initial = {'status': requested_status})
myform.fields['status'].editable = False
But the user can still change that field.
What's the real way to accomplish what I'm after?
Step 1: Disable the frontend widget
Use the HTML readonly attribute:
http://www.w3schools.com/tags/att_input_readonly.asp
Or disabled attribute:
http://www.w3.org/TR/html401/interact/forms.html#adef-disabled
You can inject arbitrary HTML key value pairs via the widget attrs property:
myform.fields['status'].widget.attrs['readonly'] = True # text input
myform.fields['status'].widget.attrs['disabled'] = True # radio / checkbox
Step 2: Ensure the field is effectively disabled on backend
Override your clean method for your field so that regardless of POST input (somebody can fake a POST, edit the raw HTML, etc.) you get the field value that already exists.
def clean_status(self):
# when field is cleaned, we always return the existing model field.
return self.instance.status
From django 1.9:
from django.forms import Textarea
class MyModelForm(forms.ModelForm):
class Meta:
model = MyModel
fields = '__all__'
widgets = {'my_field_in_my_model': Textarea(attrs={'cols':80,'rows':1}),}
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self.fields['my_field_in_my_model'].disabled = True
Have you tried using the exclude function?
something like this
class PartialAuthorForm(ModelForm):
class Meta:
model = Author
fields = ('name', 'title')
class PartialAuthorForm(ModelForm):
class Meta:
model = Author
exclude = ('birth_date',)
Reference Here
Just customize the widget instance for the status field:
class MyModel(models.Model):
REGULAR = 1
PREMIUM = 2
STATUS_CHOICES = ((REGULAR, "regular"), (PREMIUM, "premium"))
name = models.CharField(max_length=30)
status = models.IntegerField(choices = STATUS_CHOICES, default = REGULAR)
class MyForm(forms.ModelForm):
status = forms.CharField(widget=forms.TextInput(attrs={'readonly':'True'}))
class Meta:
model = models.MyModel
see: Django Documentation
There is a very easy way of doing it:
class GenerateCertificate(models.Model):
field_name = models.CharField(
max_length=15,
editable=False)
def __unicode__(self):
return unicode(self.field_name)
The editable=False will make the field disabled for editing.
I have a situation where I want to use the Meta options of unique_together to enforce a certain rule, here's the intermediary model:
class UserProfileExtension(models.Model):
extension = models.ForeignKey(Extension, unique=False)
userprofile = models.ForeignKey(UserProfile, unique=False)
user = models.ForeignKey(User, unique=False)
class Meta:
unique_together = (("userprofile", "extension"),
("user", "extension"),
# How can I enforce UserProfile's Client
# and Extension to be unique? This obviously
# doesn't work, but is this idea possible without
# creating another FK in my intermediary model
("userprofile__client", "extension"))
and here's UserProfile:
class UserProfile(models.Model):
user = models.ForeignKey(User, unique=True)
client = models.ForeignKey(Client)
Thanks.
You can't.
The unique_together clause is directly translated to the SQL unique index. And you can only set those on columns of a single table, not a combination of several tables.
You can add validation for it yourself though, simply overwrite the validate_unique method and add this validation to it.
Docs: http://docs.djangoproject.com/en/dev/ref/models/instances/#django.db.models.Model.validate_unique
My 2 cents, complementing the accepted response from #Wolph
You can add validation for it yourself though, simply overwrite the validate_unique method and add this validation to it.
This is a working example code someone could find usefull.
from django.core.exceptions import ValidationError
class MyModel(models.Model):
fk = models.ForeignKey(AnotherModel, on_delete=models.CASCADE)
my_field = models.CharField(...) # whatever
def validate_unique(self, *args, **kwargs):
super().validate_unique(*args, **kwargs)
if self.__class__.objects.\
filter(fk=self.fk, my_field=self.my_field).\
exists():
raise ValidationError(
message='MyModel with this (fk, my_field) already exists.',
code='unique_together',
)
My solution was to use Django's get_or_create. By using get_or_create, a useless get will occur if the row already exists in the database, and the row will be created if it does not exist.
Example:
extension = Extension.objects.get(pk=someExtensionPK)
userProfile = UserProfile.objects.get(pk=someUserProfilePK)
UserProfileExtension.objects.get_or_create(extension=extension, userprofile=userProfile)
From django 2.2+ versions, it is suggested to use constraint & Index as model class meta option:
https://docs.djangoproject.com/en/3.2/ref/models/options/#django.db.models.Options.unique_together
https://docs.djangoproject.com/en/3.2/ref/models/options/#django.db.models.Options.constraints
class UniqueConstraintModel(models.Model):
race_name = models.CharField(max_length=100)
position = models.IntegerField()
global_id = models.IntegerField()
fancy_conditions = models.IntegerField(null=True)
class Meta:
constraints = [
models.UniqueConstraint(
name="unique_constraint_model_global_id_uniq",
fields=('global_id',),
),
models.UniqueConstraint(
name="unique_constraint_model_fancy_1_uniq",
fields=('fancy_conditions',),
condition=models.Q(global_id__lte=1)
),
models.UniqueConstraint(
name="unique_constraint_model_fancy_3_uniq",
fields=('fancy_conditions',),
condition=models.Q(global_id__gte=3)
),
models.UniqueConstraint(
name="unique_constraint_model_together_uniq",
fields=('race_name', 'position'),
condition=models.Q(race_name='example'),
)
]
You need to call Models.full_clean() method to call validate_unique for foreignKey. You can override save() to call this
class UserProfileExtension(models.Model):
extension = models.ForeignKey(Extension, unique=False)
userprofile = models.ForeignKey(UserProfile, unique=False)
user = models.ForeignKey(User, unique=False)
def save(self, *args, **kwargs):
self.full_clean()
super().save(*args, **kwargs)
class Meta:
unique_together = (("userprofile", "extension"),
("user", "extension"),
# How can I enforce UserProfile's Client
# and Extension to be unique? This obviously
# doesn't work, but is this idea possible without
# creating another FK in my intermediary model
("userprofile__client", "extension"))
from django.core.exceptions import ValidationError
.....
class UserProfileExtension(models.Model):
extension = models.ForeignKey(Extension, unique=False)
userprofile = models.ForeignKey(UserProfile, unique=False)
user = models.ForeignKey(User, unique=False)
def validate_unique(self, *args, **kwargs):
super(UserProfileExtension, self).validate_unique(*args, **kwargs)
query = UserProfileExtension.objects.filter(extension=self.extension)
if query.filter(userprofile__client=self.userprofile.client).exists():
raise ValidationError({'extension':['Extension already exits for userprofile__client',]})
The first query is to filter all records in UserProfileExtension model which has the same extension we are putting in the current record.
Then we filter the query returned to find if it already contains userprofile__client which we are passing in the current record.
Another possible solution is to add this on your save method from your Model:
def save(self, *args, **kwargs):
unique = self.__class__.objects.filter( extension =self.extension, userprofile=self.userprofile )
if unique.exists():
self.id = unique[0].id
super(self.__class__, self).save(*args, **kwargs)
If I have a Django form such as:
class ContactForm(forms.Form):
subject = forms.CharField(max_length=100)
message = forms.CharField()
sender = forms.EmailField()
And I call the as_table() method of an instance of this form, Django will render the fields as the same order as specified above.
My question is how does Django know the order that class variables where defined?
(Also how do I override this order, for example when I want to add a field from the classe's init method?)
New to Django 1.9 is Form.field_order and Form.order_fields().
# forms.Form example
class SignupForm(forms.Form):
password = ...
email = ...
username = ...
field_order = ['username', 'email', 'password']
# forms.ModelForm example
class UserAccount(forms.ModelForm):
custom_field = models.CharField(max_length=254)
def Meta:
model = User
fields = ('username', 'email')
field_order = ['username', 'custom_field', 'password']
[NOTE: this answer is now pretty completely outdated - please see the discussion below it, and more recent answers].
If f is a form, its fields are f.fields, which is a django.utils.datastructures.SortedDict (it presents the items in the order they are added). After form construction f.fields has a keyOrder attribute, which is a list containing the field names in the order they should be presented. You can set this to the correct ordering (though you need to exercise care to ensure you don't omit items or add extras).
Here's an example I just created in my current project:
class PrivEdit(ModelForm):
def __init__(self, *args, **kw):
super(ModelForm, self).__init__(*args, **kw)
self.fields.keyOrder = [
'super_user',
'all_districts',
'multi_district',
'all_schools',
'manage_users',
'direct_login',
'student_detail',
'license']
class Meta:
model = Privilege
I went ahead and answered my own question. Here's the answer for future reference:
In Django form.py does some dark magic using the __new__ method to load your class variables ultimately into self.fields in the order defined in the class. self.fields is a Django SortedDict instance (defined in datastructures.py).
So to override this, say in my example you wanted sender to come first but needed to add it in an init method, you would do:
class ContactForm(forms.Form):
subject = forms.CharField(max_length=100)
message = forms.CharField()
def __init__(self,*args,**kwargs):
forms.Form.__init__(self,*args,**kwargs)
#first argument, index is the position of the field you want it to come before
self.fields.insert(0,'sender',forms.EmailField(initial=str(time.time())))
Fields are listed in the order they are defined in ModelClass._meta.fields. But if you want to change order in Form, you can do by using keyOrder function.
For example :
class ContestForm(ModelForm):
class Meta:
model = Contest
exclude=('create_date', 'company')
def __init__(self, *args, **kwargs):
super(ContestForm, self).__init__(*args, **kwargs)
self.fields.keyOrder = [
'name',
'description',
'image',
'video_link',
'category']
With Django >= 1.7 your must modify ContactForm.base_fields as below:
from collections import OrderedDict
...
class ContactForm(forms.Form):
...
ContactForm.base_fields = OrderedDict(
(k, ContactForm.base_fields[k])
for k in ['your', 'field', 'in', 'order']
)
This trick is used in Django Admin PasswordChangeForm: Source on Github
Form fields have an attribute for creation order, called creation_counter. .fields attribute is a dictionary, so simple adding to dictionary and changing creation_counter attributes in all fields to reflect new ordering should suffice (never tried this, though).
Use a counter in the Field class. Sort by that counter:
import operator
import itertools
class Field(object):
_counter = itertools.count()
def __init__(self):
self.count = Field._counter.next()
self.name = ''
def __repr__(self):
return "Field(%r)" % self.name
class MyForm(object):
b = Field()
a = Field()
c = Field()
def __init__(self):
self.fields = []
for field_name in dir(self):
field = getattr(self, field_name)
if isinstance(field, Field):
field.name = field_name
self.fields.append(field)
self.fields.sort(key=operator.attrgetter('count'))
m = MyForm()
print m.fields # in defined order
Output:
[Field('b'), Field('a'), Field('c')]
If either fields = '__all__':
class AuthorForm(ModelForm):
class Meta:
model = Author
fields = '__all__'
or exclude are used:
class PartialAuthorForm(ModelForm):
class Meta:
model = Author
exclude = ['title']
Then Django references the order of fields as defined in the model. This just caught me out, so I thought I'd mention it. It's referenced in the ModelForm docs:
If either of these are used, the order the fields appear in the form will be the order the fields are defined in the model, with ManyToManyField instances appearing last.
As of Django 1.7 forms use OrderedDict which does not support the append operator. So you have to rebuild the dictionary from scratch...
class ChecklistForm(forms.ModelForm):
class Meta:
model = Checklist
fields = ['name', 'email', 'website']
def __init__(self, guide, *args, **kwargs):
self.guide = guide
super(ChecklistForm, self).__init__(*args, **kwargs)
new_fields = OrderedDict()
for tier, tasks in guide.tiers().items():
questions = [(t['task'], t['question']) for t in tasks if 'question' in t]
new_fields[tier.lower()] = forms.MultipleChoiceField(
label=tier,
widget=forms.CheckboxSelectMultiple(),
choices=questions,
help_text='desired set of site features'
)
new_fields['name'] = self.fields['name']
new_fields['email'] = self.fields['email']
new_fields['website'] = self.fields['website']
self.fields = new_fields
For future reference: things have changed a bit since newforms. This is one way of reordering fields from base formclasses you have no control over:
def move_field_before(form, field, before_field):
content = form.base_fields[field]
del(form.base_fields[field])
insert_at = list(form.base_fields).index(before_field)
form.base_fields.insert(insert_at, field, content)
return form
Also, there's a little bit of documentation about the SortedDict that base_fields uses here: http://code.djangoproject.com/wiki/SortedDict
The easiest way to order fields in django 1.9 forms is to use field_order in your form Form.field_order
Here is a small example
class ContactForm(forms.Form):
subject = forms.CharField(max_length=100)
message = forms.CharField()
sender = forms.EmailField()
field_order = ['sender','message','subject']
This will show everything in the order you specified in field_order dict.
Using fields in inner Meta class is what worked for me on Django==1.6.5:
#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""
Example form declaration with custom field order.
"""
from django import forms
from app.models import AppModel
class ExampleModelForm(forms.ModelForm):
"""
An example model form for ``AppModel``.
"""
field1 = forms.CharField()
field2 = forms.CharField()
class Meta:
model = AppModel
fields = ['field2', 'field1']
As simple as that.
I've used this to move fields about:
def move_field_before(frm, field_name, before_name):
fld = frm.fields.pop(field_name)
pos = frm.fields.keys().index(before_name)
frm.fields.insert(pos, field_name, fld)
This works in 1.5 and I'm reasonably sure it still works in more recent versions.
To add something, you can use this (Django 3+):
class ...(forms.ModelForm):
field = ...
class Meta:
model = Xxxxxx
fields = '__all__'
field_order = ['field', '__all__']
__all__ works
It has to do with the meta class that is used in defining the form class. I think it keeps an internal list of the fields and if you insert into the middle of the list it might work. It has been a while since I looked at that code.
None of these answers worked for me, Actually, you do not have to do anything custom, you can just order the fields in the order you want in your Model class. For eg ... the below code
from django.db import models
class Student(models.Model):
class Meta:
verbose_name_plural = "categories"
id = models.AutoField(primary_key=True)
name = models.CharField(max_length=300)
nick_name = models.CharField(max_length=300)
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now=True)
def __str__(self):
return self.name
Your admin interface for model Will display the fields exactly in the same order in which you have declared in this case it will be (id, name, nick_name )
The order of the fields in the form depends on the order of the enumeration in the View , tested in Django 4.0.5.
class Sec_CreateView(CreateView):
model = Sec
template_name = 'forms/sec_create.html'
fields = ['rto', 'ssid', 'lic', 'IPv4', 'vlans']