django model forms filter queryset - django

I have the following model:
class Article(models.Model):
title = models.CharField()
description = models.TextField()
author = models.ForeignKey(User)
class Rating(models.Model):
value = models.IntegerField(choices=RATING_CHOICES)
additional_note = models.TextField(null=True, blank=True)
from_user = models.ForeignKey(User, related_name='from_user')
to_user = models.ForeignKey(User, related_name='to_user')
rated_article = models.ForeignKey(Article, null=True, blank=True)
dtobject = models.DateTimeField(auto_now_add=True)
Based upon the above model, i have created a model form, as follows:
Model Forms:
class RatingForm(ModelForm):
class Meta:
model = Rating
exclude = ('from_user', 'dtobject')
Excluding from_user because the request.user is the from_user.
The form renders well, but in to_user in the dropdown field, the author can rate himself as well. So i would want the current_user's name to populate in the dropdown field. How do i do it?

Override __init__ to remove current user from the to_user choices.
Update: More Explanation
ForeignKey uses ModelChoiceField whose choices are queryset. So in __init__ you have to remove the current user from to_user's queryset.
Update 2: Example
class RatingForm(ModelForm):
def __init__(self, current_user, *args, **kwargs):
super(RatingForm, self).__init__(*args, **kwargs)
self.fields['to_user'].queryset = self.fields['to_user'].queryset.exclude(id=current_user.id)
class Meta:
model = Rating
exclude = ('from_user', 'dtobject')
Now in the view where you create RatingForm object pass request.user as keyword argument current_user like this.
form = RatingForm(current_user=request.user)

Related

Cannot assign "id": "Product.category" must be a "CategoryProduct" instance

i'm working on a django project and i got this error (Cannot assign "'11'": "Product.category" must be a "CategoryProduct" instance.) anyone here can help me please.
Model:
class Product(models.Model):
name = models.CharField("Nombre", max_length=150)
category = models.ForeignKey(CategoryProduct, on_delete=models.SET_NULL, null=True, related_name='category')
def __str__(self):
return self.name
View:
class ProductCreateView(CreateView):
model = Product
form_class = ProductForm
success_url = '/adminpanel/products/'
def post(self, request, *args, **kwargs):
form = self.get_form()
category = CategoryProduct.objects.get(id=request.POST['category'])
if form.is_valid():
product = form.save(commit=False)
product.category = category
product.save()
Form:
class ProductForm(forms.ModelForm):
name = forms.CharField(max_length=150, label="Nombre")
category = forms.ChoiceField(choices=[(obj.id, obj.name) for obj in CategoryProduct.objects.all()], label="Categoría")
class Meta:
model = Product
fields = ['name', 'category']
You can let Django's ModelForm do its work, this will create a ModelChoiceField [Django-doc], which is where the system gets stuck: it tries to assign the primary key to category, but that should be a ProductCategory object, so you can let Django handle this with:
class ProductForm(forms.ModelForm):
class Meta:
model = Product
fields = ['name', 'category']
If you want to specify a different label, you can use the verbose_name=… [Django-doc] from the model field, or specify this in the labels options [Django-doc] of the Meta of the ProductForm. So you can specify Categoria with:
class Product(models.Model):
name = models.CharField('Nombre', max_length=150)
category = models.ForeignKey(
CategoryProduct,
on_delete=models.SET_NULL,
null=True,
related_name='products',
verbose_name='Categoria'
)
def __str__(self):
return self.name
then the CreateView can just use its boilerplate logic:
class ProductCreateView(CreateView):
model = Product
form_class = ProductForm
success_url = '/adminpanel/products/'
Note: The related_name=… parameter [Django-doc]
is the name of the relation in reverse, so from the Category model to the Product
model in this case. Therefore it (often) makes not much sense to name it the
same as the forward relation. You thus might want to consider renaming the category relation to products.

How to retrieve data from model that current user created and list it for another model's field in django

Let us imagine that I have two models.
First model contains curse details and user that created this course
class Course(models.Model):
course_name = models.CharField(max_length=100, null=False)
description = models.CharField(max_length=255)
user_profile = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE)
and my second model is:
class Lesson(models.Model):
course = models.OneToOneField(Course, on_delete=models.CASCADE) #
# inside the course I want my APIVIEW to list only the courses that current user created.
# OnetoOne relationship does not solve the problem.
status = models.CharField(choices=STATUS, null=False, default=GOZLEMEDE,max_length=20)
tariffs = models.FloatField(max_length=5,null=False,default=0.00)
continues_off = models.CharField(max_length=2)
user_profile = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE)
My serializers for both Models:
class LessonSerializer(serializers.ModelSerializer):
class Meta:
model = models.Lesson
fields = ('course', 'status', 'tariffs', 'continues_off', 'user_profile')
def create(self, validated_data):
lesson = models.Lesson.objects.create(
course = validated_data['course'],
status = validated_data['status'],
tariffs=validated_data['tariffs'],
continues_off=validated_data['continues_off'],
user_profile=validated_data['user_profile']
)
return lesson
class CourseSerializer(serializers.ModelSerializer):
"""Serializers Course content"""
class Meta:
model = models.Course
fields = '__all__'
def create(self,validated_data):
course = models.Course.objects.create(
course_name = validated_data['course_name'],
description=validated_data['description'],
user_profile=validated_data['user_profile']
)
return course
My Viewset:
class LessonViewset(viewsets.ModelViewSet):
model = models.Lesson
serializer_class = serializers.LessonSerializer
authentication_classes = (SessionAuthentication,)
permission_classes = (IsAuthenticated,BasePermission,)
def get_queryset(self):
user_current = self.request.user.id
return models.Lesson.objects.filter(user_profile=user_current)
How can I get the desired result. I want to get the courses for the current user and show them as a dropdown list in my API view. Just only the courses that user created should be in the dropdown list not all.
OnetoOne relationship gives all results of course table.
i think change your view code to :
def get_queryset(self,id):
return model.objects.filter(user_profile=id)
#You do not need to call it again when you put the Lesson on the model
\

How to filter data dynamically by supply values from form using django

I want to filter Blog Post objects or records based on the Post Category and a User that uploaded the Post record, it gives me an error when I try to do filter, this is the error.
ValueError at /dashboard/filter-post/
The QuerySet value for an exact lookup must be limited to one result using slicing.
Here is my models.py
class Category(models.Model):
cat_name = models.CharField(max_length=100, verbose_name='Category Name')
cat_desc = models.TextField(blank=True, null=True)
def __str__(self):
return self.cat_name
class Meta():
verbose_name_plural='Category'
class Post(models.Model):
pst_title = models.CharField(max_length=150)
pst_image = models.ImageField(blank=True, null=True, upload_to='uploads/')
user = models.ForeignKey(User, on_delete=models.CASCADE)
category = models.ManyToManyField(Category)
content = models.TextField()
created = models.DateTimeField(auto_now_add=True)
def __str__(self):
return self.pst_title
#property
def img_url(self):
if self.pst_image:
return self.pst_image.url
on forms.py
class FilterForm(forms.ModelForm):
user = forms.ModelChoiceField(
queryset=User.objects.all(),
widget=forms.Select(attrs={'class': 'form-control'}))
category = forms.ModelMultipleChoiceField(
queryset=Category.objects.all(),
widget=forms.SelectMultiple(attrs={'class': 'form-control js-example-disabled-results'}))
catch_bot = forms.CharField(required=False,
widget=forms.HiddenInput, validators=[validators.MaxLengthValidator(0)])
class Meta():
fields = ['user', 'category' ]
model = Post
on views.py
def filter_post(request):
post = FilterForm(request.GET)
queryset = Post.objects.all()
if post.is_valid():
user=post.cleaned_data.get('user')
category=post.cleaned_data.get('category')
if user and category:
queryset = queryset.filter(user__username=user, category__cat_name=category)
return render(request, 'backend/filter-post.html', {'query':queryset, 'post':post})
I am having challenges properly filtering this in my views any help?
Try this:
instead of this:
queryset = queryset.filter(user__username=user, category__cat_name=category)
use this:
queryset = queryset.filter(user=user, category=category)
Also don't name your model fields after the model name, just use name instead of pst_name or cat_name, you will see that when you will try access these values there will be no confusion.
UPDATE
Ok, maybe try to rewrite your view like this:
def filter_post(request):
posts = Post.objects.all()
form = FilterForm(request.GET) # its best practice to call your form instance `form` in the view so that the next line has better readability
if form.is_valid():
user=post.cleaned_data['user']
category=post.cleaned_data['category']
if user:
posts = posts.filter(user=user)
if category:
posts = posts.filter(category=category)
return render(request, 'backend/filter-post.html', {'posts':posts})

django checkbox select multiple models

Hi I have the following django model:
class Issue(models.Model):
title = models.CharField(max_length=200)
date = models.DateTimeField(auto_now=True)
assignee = models.ForeignKey(User, on_delete=models.CASCADE, related_name='assignee')
owner = models.ForeignKey(User, on_delete=models.CASCADE, related_name='owner', null=True, blank=True)
description = models.TextField()
state = models.IntegerField(choices=STATUS_CHOICES, default=1)
priority = models.IntegerField(choices=RELEVANCE_CHOICES, default=2)
expired_date = models.DateField(auto_now=False, null=True, blank=True)
and a form which allow a user to create an Issue instance:
class IssueForm(forms.ModelForm):
class Meta:
model = Issue
fields = ('title', 'description', 'assignee', 'state', 'priority', 'expired_date')
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self.fields['title'].label = "Titolo"
self.fields['description'].label = "Descrizione"
self.fields['state'].label = "Stato"
self.fields['priority'].label = "Priorità"
self.fields['expired_date'].label = "Termine"
self.fields['expired_date'].widget.attrs.update({'class': 'datepicker'})
self.fields['assignee'] = forms.MultipleChoiceField(
choices=self.fields['assignee'].choices,
widget=forms.CheckboxSelectMultiple,
label=("Assegnatario")
)
def clean(self):
cleaned_data = super().clean()
user_id = [i for i in cleaned_data['assignee']]
cleaned_data['assignee'] = [User.objects.get(id=i) for i in user_id]
return cleaned_data
I render this form and the field assignee is a checkbox.
I would like to be able to choose several assignee for the same issue, but I got an error because the Issue model expect just one User instance
How can I modify my model Issue in order to get more than one user ?
Thanks
you can create a new class and name it Issue_Instance where every Issue Object can have an assignee as a foreign key the problem that the relation is one to many because you have to choose more than one assignee and Django doesn't support the idea of having Array or List of Foreign Keys(I don't know any frame works that do :=) ) so I would suggest creating a new class or make the foreign key relation one-to-many key field read about it it will be very useful to solve your problem

Change Label Generic Inline Admin

I the following in the models.py:
class Item(models.Model):
date = models.DateField(_('date'), blank=True, null=True)
description = models.CharField(_('description'), max_length=255)
content_type = models.ForeignKey(ContentType, verbose_name=_('content type'))
object_id = models.PositiveIntegerField(_('object id'), db_index=True)
object = generic.GenericForeignKey('content_type', 'object_id')
class ItemAccountAmountRef(Item):
""" Items of which a Quote or an Invoice exists. """
amount = models.DecimalField(max_digits=10, decimal_places=2)
reference = models.CharField(max_length=200)
debit_account = models.ForeignKey(Account, related_name='receivables_receipt_debit_account')
credit_account = models.ForeignKey(Account, related_name='receivables_receipt_credit_account')
class PaymentItem(ItemAccountAmountRef):
pass
class Payment(models.Model):
invoice = models.ManyToManyField(Invoice, null=True, blank=True)
date = models.DateField('date')
attachments = generic.GenericRelation(Attachment)
site = models.ForeignKey(Site, related_name='payment_site', null=True, blank=True
items = generic.GenericRelation(PaymentItem)
in the admin.py:
class PaymentItemInline(generic.GenericTabularInline):
model = PaymentItem
form = PaymentItemForm
class PaymentAdmin(admin.ModelAdmin):
inlines = [PaymentItemInline]
in forms.py:
class PaymentItemForm(forms.ModelForm):
def __init__(self, *args, **kwargs):
super(PaymentItemForm, self).__init__(*args, **kwargs)
self.fields['credit_account'].label = "Bank Account"
In the PaymentItemInline the label is not changing. I have tried changing other attributes e.g. class which work. If I run through the init in debug mode I can see that the label variable is changing however when the form is rendered the field is still labelled credit account. Any suggestions?
You're 98% of the way there. Instead of trying to futz with the form field in __init__, just redefine it in your ModelForm. If you name it the same thing, django will be able to figure out that it is supposed to validate & save to the ForeignKey field. You can use the same formula to change a Field or Widget completely for a given field in a ModelForm.
You can find the default form field types for each model field type here: https://docs.djangoproject.com/en/dev/topics/forms/modelforms/#field-types
class PaymentItemForm(forms.ModelForm):
credit_account = forms.ModelChoiceField(label="Bank Account", queryset=Account.objects.all())
That's it. No need to override any functions at all : )
Incidentally, the docs for this field are here: https://docs.djangoproject.com/en/dev/ref/forms/fields/#modelchoicefield