Validating data in Django ModelForm - django

And i have a simple modelform for Package
from models import Package
from django import forms
class PackageForm(forms.ModelForm):
class Meta:
model= Package
fields= ['name', 'version', 'url', 'description', 'arch', 'dependancies', 'conflicts', 'file']
How can i ask the modelform to check, within validation, if the file extension (class is FileField) is .sh for example?
is there a way to put this in modelform? of can i only manage it in a view?
Thanks
Edit:
Also, forgot to ask, the model has a Foreignkey to the auth User model... which is going to contain the current user.. how can modelform manage that?
Thanks again
Thanks for the answer! i'm getting hold of this.. although i encounter a problem
Package contains a foreignkey to django.contrib.auth.models User model,
When the form is processed how can i tell the modelform to pass the current user object to the model instance?
i thought of this...
views.py
def add(request):
if request.method == 'POST':
the_model= PackageForm(request.user, request.POST, request.FILES)
if the_model.is_valid():
the_model.save()
i overwrited the init in modelform:
from models import Package
from django import forms
class PackageForm(forms.ModelForm):
def __init__(self,user,*args,**kwargs):
super (PackageForm,self ).__init__(*args,**kwargs) # populates the post
self.fields['maintainer_name'].queryset = user # adds the user object passed by add in views.py
class Meta:
model= Package
fields= ['name', 'version', 'url', 'description', 'arch', 'dependancies', 'conflicts', 'file']
manteiner_name is the ForeignKey(User) object...
it gives me a keyerror :( that's not good...
Any solutions?
Thanks!

You should read the Django documentation on doing extra validation:
You just need to define a clean_file() method.

Related

django don't pass form in html in templates [duplicate]

Could anyone explain to me similarities and differences of Django's forms.Form & forms.ModelForm?
Forms created from forms.Form are manually configured by you. You're better off using these for forms that do not directly interact with models. For example a contact form, or a newsletter subscription form, where you might not necessarily be interacting with the database.
Where as a form created from forms.ModelForm will be automatically created and then can later be tweaked by you. The best examples really are from the superb documentation provided on the Django website.
forms.Form:
Documentation: Form objects
Example of a normal form created with forms.Form:
from django import forms
class ContactForm(forms.Form):
subject = forms.CharField(max_length=100)
message = forms.CharField()
sender = forms.EmailField()
cc_myself = forms.BooleanField(required=False)
forms.ModelForm:
Documentation: Creating forms from models
Straight from the docs:
If your form is going to be used to
directly add or edit a Django model,
you can use a ModelForm to avoid
duplicating your model description.
Example of a model form created with forms.Modelform:
from django.forms import ModelForm
from . import models
# Create the form class.
class ArticleForm(ModelForm):
class Meta:
model = models.Article
This form automatically has all the same field types as the Article model it was created from.
The similarities are that they both generate sets of form inputs using widgets, and both validate data sent by the browser. The differences are that ModelForm gets its field definition from a specified model class, and also has methods that deal with saving of the underlying model to the database.
Here's how I'm extending the builtin UserCreationForm myapp/forms.py:
from django import forms
from django.contrib.auth.forms import UserCreationForm
class RegisterForm(UserCreationForm):
first_name = forms.CharField(max_length=30)
last_name = forms.CharField(max_length=30)
email = forms.CharField(max_length=75)
class Meta(UserCreationForm.Meta):
fields = ('username','first_name','last_name', 'email')
The difference is simple, ModelForm serves to create the form of a Model.
meaning that Model is designed to create kind of schema of your table where you will save data from form submission and ModelForm simply creates a form of the model (from the schema of the table)
# This creates a form from model Article
class ArticleForm(ModelForm):
class Meta:
model = Article
fields = ['pub_date', 'headline', 'content', 'reporter']
Form is a common form that is unrelated to your database (model ).
# A simple form to display Subject and Message field
class ContactForm(forms.Form):
subject = forms.CharField(max_length=100)
message = forms.CharField(widget=forms.Textarea)
To say in other words,
If you have a model in your app and you want to create a Form to enter data in that model (and by it to a db) use forms.ModelForm
If you simple want to create a form using django use form.Form
But you can also use this together:
from django import forms
# A simple form to display Subject and Message field
class ContactForm(forms.ModelForm):
subject = forms.CharField(max_length=100)
message = forms.CharField(widget=forms.Textarea)
class Meta:
model = Contact #when you have this model
fields = [
'subject',
'message',
]

problem in form django have problem in form django i wannt someone to selve [duplicate]

Could anyone explain to me similarities and differences of Django's forms.Form & forms.ModelForm?
Forms created from forms.Form are manually configured by you. You're better off using these for forms that do not directly interact with models. For example a contact form, or a newsletter subscription form, where you might not necessarily be interacting with the database.
Where as a form created from forms.ModelForm will be automatically created and then can later be tweaked by you. The best examples really are from the superb documentation provided on the Django website.
forms.Form:
Documentation: Form objects
Example of a normal form created with forms.Form:
from django import forms
class ContactForm(forms.Form):
subject = forms.CharField(max_length=100)
message = forms.CharField()
sender = forms.EmailField()
cc_myself = forms.BooleanField(required=False)
forms.ModelForm:
Documentation: Creating forms from models
Straight from the docs:
If your form is going to be used to
directly add or edit a Django model,
you can use a ModelForm to avoid
duplicating your model description.
Example of a model form created with forms.Modelform:
from django.forms import ModelForm
from . import models
# Create the form class.
class ArticleForm(ModelForm):
class Meta:
model = models.Article
This form automatically has all the same field types as the Article model it was created from.
The similarities are that they both generate sets of form inputs using widgets, and both validate data sent by the browser. The differences are that ModelForm gets its field definition from a specified model class, and also has methods that deal with saving of the underlying model to the database.
Here's how I'm extending the builtin UserCreationForm myapp/forms.py:
from django import forms
from django.contrib.auth.forms import UserCreationForm
class RegisterForm(UserCreationForm):
first_name = forms.CharField(max_length=30)
last_name = forms.CharField(max_length=30)
email = forms.CharField(max_length=75)
class Meta(UserCreationForm.Meta):
fields = ('username','first_name','last_name', 'email')
The difference is simple, ModelForm serves to create the form of a Model.
meaning that Model is designed to create kind of schema of your table where you will save data from form submission and ModelForm simply creates a form of the model (from the schema of the table)
# This creates a form from model Article
class ArticleForm(ModelForm):
class Meta:
model = Article
fields = ['pub_date', 'headline', 'content', 'reporter']
Form is a common form that is unrelated to your database (model ).
# A simple form to display Subject and Message field
class ContactForm(forms.Form):
subject = forms.CharField(max_length=100)
message = forms.CharField(widget=forms.Textarea)
To say in other words,
If you have a model in your app and you want to create a Form to enter data in that model (and by it to a db) use forms.ModelForm
If you simple want to create a form using django use form.Form
But you can also use this together:
from django import forms
# A simple form to display Subject and Message field
class ContactForm(forms.ModelForm):
subject = forms.CharField(max_length=100)
message = forms.CharField(widget=forms.Textarea)
class Meta:
model = Contact #when you have this model
fields = [
'subject',
'message',
]

Django model validator not working on create

I have model with a field validator
from django.db import models
from django.core.validators import MinValueValidator, MaxValueValidator
class MyModel(model.Model):
name = models.CharField()
size = models.IntegerField(validators=[MinValueValidator(1),MaxValueValidator(10)])
The validator is working well in the django admin panel ,while I try to enter the value more than 10, it's showing me the error message 'Ensure this value is less than or equal to 10' and does not allow to save.
But, when I try in the django shell, the validator is not working, it allows to save the record, I don't know why is the validator not throwing error message here.
>>>form app.models import MyModel
>>>MyModel.objects.create(name="Some Name", size=15)
<MyModel: Some Name>
Can you please suggest me if anything I missed or any mistake i did here. Kindly help me to solve this problem, it will be very greatfull for me, Thanks in advance.
Django validation is mostly application level validation and not validation at DB level. Also Model validation is not run automatically on save/create of the model. If you want to validate your values at certain time in your code then you need to do it manually.
For example:
from django.core.exceptions import ValidationError
form app.models import MyModel
instance = MyModel(name="Some Name", size=15)
try:
instance.full_clean()
except ValidationError:
# Do something when validation is not passing
else:
# Validation is ok we will save the instance
instance.save()
More info you can see at django's documentation https://docs.djangoproject.com/en/1.10/ref/models/instances/#validating-objects
In administration it works automatically because all model forms (ModelForm) will run model validation process alongside form validation.
If you need to validate data because it is coming from untrusted source (user input) you need to use ModelForms and save the model only when the form is valid.
The validator only works when you are using models in a ModelForm.
https://docs.djangoproject.com/en/dev/ref/validators/#how-validators-are-run
You can perform model validation by overidding clean() and full_clean() methods
Validators work only with the Forms and model forms. Can't be used with the model definition because it runs at the app side not the DB side.
You can add this to your model and call it in save().
def save(self, *args, **kwargs):
self.run_validators()
super().save(*args, **kwargs)
def run_validators(self) -> None:
for field_name, field_value in model_to_dict(self).items():
model_field = getattr(UserSearchHistory, field_name)
field = getattr(model_field, 'field', object())
validators = getattr(field, 'validators', list())
for validator_func in validators:
if field_value is not None:
validator_func(field_value)
From django documentation:
Note that validators will not be run automatically when you save a
model, but if you are using a ModelForm, it will run your validators
on any fields that are included in your form.
https://docs.djangoproject.com/en/3.1/ref/validators/#how-validators-are-run
I ran into the same issue.
So the validators only work when you are using Forms and Model Form to fill it.
However, by creating in shell, you probably wanted to test the validators before going live.
So here is the additional piece of code to help in validating the validators.
>>>form app.models import MyModel
>>>MyModel.size.field.run_validators(value=<undesirable value>)
You can not run validator in creating you must run validation in instance if not exception occurred you must save it
It is worth mentioning that model field validators
like validate_color in here:
bg_color = models.CharField(
max_length=50, default="f0f2f5", validators=[validate_color]
)
work with restf_ramework (drf) Serializer class either.
https://github.com/encode/django-rest-framework/blob/master/rest_framework/serializers.py
so validators run when you call is_valid on ModelForm (from django) or is_valid on Serializer (from rest_framework).

Django 1.4 User Admin list_filter using UserProfile field

EDIT: I updated the code to reflect one mistake in the queryset filter, where I had user__user_type, has been replaced with the correct userprofile__user_type.
I'm using Django 1.4, and I understand there's a new feature to create custom list_filters for the admin, that replaced the FilterSpec API.
I've read countless SO posts about creating custom admin list_filters, but I'm still stuck.
My use case is for a list_filter for my User objects that's referencing a field in the UserProfile Model.
So in models.py:
class UserProfile(models.Model):
user = models.OneToOneField(User, unique=True)
user_type = models.CharField(max_length=25, choices=USER_TYPES, default='Client')
...
and in admin.py:
from django.contrib import admin
from django.contrib.admin import site, ModelAdmin, ChoicesFieldListFilter
from django.contrib.auth.models import User
from django.contrib.auth.admin import UserAdmin
from models import UserProfile
class UserTypeFilter(ChoicesFieldListFilter):
title = 'User Type'
parameter_name = 'user_type'
def lookups(self, request, model_admin):
usertypes = set([c.user_type for c in UserProfile.objects.all()])
return [(c.id, c.user_type) for c in usertypes]
def queryset(self, request, queryset):
if self.value():
return queryset.filter(userprofile__user_type=self.value())
else:
return queryset
class UserAdmin(UserAdmin):
list_filter = ('is_staff', UserTypeFilter)
inlines = (UserProfileInline, )
admin.site.unregister(User)
admin.site.register(User, UserAdmin)
Here's the error I get:
'UserAdmin.list_filter[1]' is 'UserTypeFilter' which is of type FieldListFilter but is not associated with a field name.
I originally tried using the SimpleListFilter, and got this error
'unicode' object has no attribute 'id'
Which makes sense, because my user_type field is a choice field, and the choices are unicode objects.
The docs show this example:
class PersonAdmin(UserAdmin):
list_filter = ('company__name',)
But this seems to imply that 'company' is a field on the User model. Do I need to redefine my User model to include a OneToOneField for UserProfile? Or am I missing some obvious way to reference a user's profile?
Thanks,
The first error you reference seems to be specific to FieldListFilter which I've never used. I guess the point of it is to automate something related to a specific field.
I see no use for it with your example as you're supplying all options.
I'd just use a SimpleListFilter for now...
Anyways your error is that usertypes is a set of c.user_type which is a string. It has no id attribute.
You need to return [(c, c) for c in usertypes] where the first value is the value passed to your QS, and the second is the display value.
The rest doesn't need to change.

Django's forms.Form vs forms.ModelForm

Could anyone explain to me similarities and differences of Django's forms.Form & forms.ModelForm?
Forms created from forms.Form are manually configured by you. You're better off using these for forms that do not directly interact with models. For example a contact form, or a newsletter subscription form, where you might not necessarily be interacting with the database.
Where as a form created from forms.ModelForm will be automatically created and then can later be tweaked by you. The best examples really are from the superb documentation provided on the Django website.
forms.Form:
Documentation: Form objects
Example of a normal form created with forms.Form:
from django import forms
class ContactForm(forms.Form):
subject = forms.CharField(max_length=100)
message = forms.CharField()
sender = forms.EmailField()
cc_myself = forms.BooleanField(required=False)
forms.ModelForm:
Documentation: Creating forms from models
Straight from the docs:
If your form is going to be used to
directly add or edit a Django model,
you can use a ModelForm to avoid
duplicating your model description.
Example of a model form created with forms.Modelform:
from django.forms import ModelForm
from . import models
# Create the form class.
class ArticleForm(ModelForm):
class Meta:
model = models.Article
This form automatically has all the same field types as the Article model it was created from.
The similarities are that they both generate sets of form inputs using widgets, and both validate data sent by the browser. The differences are that ModelForm gets its field definition from a specified model class, and also has methods that deal with saving of the underlying model to the database.
Here's how I'm extending the builtin UserCreationForm myapp/forms.py:
from django import forms
from django.contrib.auth.forms import UserCreationForm
class RegisterForm(UserCreationForm):
first_name = forms.CharField(max_length=30)
last_name = forms.CharField(max_length=30)
email = forms.CharField(max_length=75)
class Meta(UserCreationForm.Meta):
fields = ('username','first_name','last_name', 'email')
The difference is simple, ModelForm serves to create the form of a Model.
meaning that Model is designed to create kind of schema of your table where you will save data from form submission and ModelForm simply creates a form of the model (from the schema of the table)
# This creates a form from model Article
class ArticleForm(ModelForm):
class Meta:
model = Article
fields = ['pub_date', 'headline', 'content', 'reporter']
Form is a common form that is unrelated to your database (model ).
# A simple form to display Subject and Message field
class ContactForm(forms.Form):
subject = forms.CharField(max_length=100)
message = forms.CharField(widget=forms.Textarea)
To say in other words,
If you have a model in your app and you want to create a Form to enter data in that model (and by it to a db) use forms.ModelForm
If you simple want to create a form using django use form.Form
But you can also use this together:
from django import forms
# A simple form to display Subject and Message field
class ContactForm(forms.ModelForm):
subject = forms.CharField(max_length=100)
message = forms.CharField(widget=forms.Textarea)
class Meta:
model = Contact #when you have this model
fields = [
'subject',
'message',
]