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Django - get data from form and return to user so they can edit/delete

New to Django and making a restuarant booking system. I have everything going to my database but now i'm trying to return the info back to the user, ideally in a similar form view to what i have, so they can edit or delete the booking.
My code so far is as follows:
models.py:
class Reservations(models.Model):
reservation form categories and attributes
name = models.CharField(max_length=50)
phone_number = models.CharField(validators=[phoneNumberRegex], max_length=16,
unique=True)
email = models.EmailField()
date = models.DateField()
time = models.CharField(choices=time_options, default="12pm", max_length=10)
number_of_party = models.IntegerField(choices=party_size, default=1)
reservation_id = models.UUIDField(primary_key=True, default=uuid.uuid4,
editable=False, max_length=15)
class Meta:
ordering = ['date']
verbose_name = 'Reservation'
verbose_name_plural = 'Reservations'
def __str__(self):
return self.name
Then my form looks like this:
form.py:
class ReservationForm(forms.ModelForm):
class Meta:
model = Reservations
fields = ['name', 'phone_number', 'email', 'date', 'time', 'number_of_party']
widgets = {
'date': DatePickerInput(format='%d-%m-%Y'),
}
Then where I think i'm really getting lost is with the views.
view.py:
class ReservationsFormView(CreateView):
model = Reservations
template_name = "reservations/reservations.html"
form_class = ReservationForm
success_url = "reservation_complete/"
def form_valid(self, form):
return super().form_valid(form)
class EditReservationView(LoginRequiredMixin, UserPassesTestMixin, UpdateView):
model = Reservations
template_name = "reservations/edit_reservations.html"
form_class = ReservationForm
success_url = "reservation_complete/"
def test_func(self):
return self.request.user == self.get_object().user
class ReservationCompleteView(CreateView):
template_name = "reservations/reservation_complete.html"
success_url = "/reservation_complete/"
form_class = ReservationForm
model = Reservations
class ReservationAccountView(TemplateView):
template_name = "reservations/reservations_account.html"
class DeleteReservationView(LoginRequiredMixin, UserPassesTestMixin, DeleteView):
""" A view to delete an reservation """
model = Reservations
success_url = "/reservations/"
def test_func(self):
return self.request.user == self.get_object().user
So basically if someone could help me extract the data and present back to the user in a html file I would greatly appreciate it.
A lot of the material online isn't using class based views but i start that way so sticking it out.
Sorry for the verbose code.
Thanks in advance

While Django's Edit, Create, etc views are quick and helpful, I find them hard to manipulate, especially if I haven't used them in a while. I recommend getting used to writing your own views, that way you can set whatever action you want the view to perform.
Let's say your URL looks like this - edit/4281ee81-a12a-4a0f-8928-2d9639903bd7/
forms.py
class EditReservationForm(forms.Form):
name = forms.CharField()
email = forms.EmailField()
views.py
class EditReservationView(LoginRequiredMixing, View):
def get(self, request, *args **kwargs):
reservation = Reservations.objects.get(uuid=kwargs['uuid'])
form = EditReservationForm(initial={"name": reservation.name, "email": reservation.email})
return render(request, "reservation/edit-reservation.html", {"form": form})
You now have a bound form to data from a specific reservation. I hope this helps. And more info on initial data here - initial form values

How to pre fill fields in a form when using django-bootstrap-modal-forms

I am using django-bootstrap-modal-forms and it works perfectly as in documentation when using fields form my model. Some of the fields are ForeignKeys and they are displayed properly for user to select a value from database table that is referenced by the key, but instead of that I need to put username of the current user.
I tried to change how the CreateView class handles fields, but with no luck. Probably doing something wrong.
models.py
class userSchoolYear(models.Model):
user_in_school = models.ForeignKey(get_user_model(), null=True, on_delete=models.CASCADE)
school = models.ForeignKey(sifMusicSchool, on_delete=models.CASCADE)
school_year = models.ForeignKey(sifSchoolYear, on_delete=models.CASCADE)
school_year_grade = models.CharField(max_length=4, choices=IZBOR_RAZREDA, default=None, null=True)
user_instrument = models.ForeignKey(instType, on_delete=models.CASCADE, default=None, null=True)
user_profesor = models.ForeignKey(profSchool, on_delete=models.CASCADE, default=None, null=True)
views.py
class SchoolYearCreateView(BSModalCreateView):
template_name = 'school_year.html'
form_class = SchoolYearForm
success_message = 'Success!'
success_url = reverse_lazy('school')
def __init__(self, *args, **kwargs):
self.form_class.user_in_school = 'johnny' ### HERE
print(user.username)
super().__init__(*args, **kwargs)
forms.py
class SchoolYearForm(BSModalForm):
class Meta:
model = userSchoolYear
fields = '__all__'

Thanks to the author Uroš Trstenjak I was able to find a solution. I was wrong trying to set field values from views.py, instead it should be done in forms.py. So, basically I had to write a init for the form and alter fields values. Uroš pointed out that at from level I can get current user from self.request.user and it did work.

CreateView doesn't save related objects

I have two models: Student and Group. A group consists of multiple students and a student can be in only one group. Here are the models:
class Group(models.Model):
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now=True)
class Student(models.Model):
first_name = models.CharField(max_length=50)
last_name = models.CharField(max_length=50)
section = models.PositiveSmallIntegerField(default=1)
group = models.ForeignKey(
Group, on_delete=models.SET_NULL, null=True, blank=True
)
I am trying to build a form where I can select multiple students to create a group.
class CreateGroupForm(forms.ModelForm):
students = forms.ModelMultipleChoiceField(
required=True,
queryset=Student.objects.all()
)
class Meta:
model = Group
fields = ('students', )
I am using the following view for the form:
class SelectGroup(CreateView):
model = Group
form_class = CreateGroupForm
template_name = 'selection.html'
success_url = reverse_lazy('test')
When I submit the form, it creates a group but the group's student_set is empty. I am guessing this is because I cannot add students to a group without saving the group first. Is there a way for me to modify this view to save the students or should I use something else?

Since students is not a field of the group model, the model form's save does not know what to do with it. You have to override the save method and handle the students field manually:
class CreateGroupForm(forms.ModelForm):
# ...
def save(self, commit=True):
# you have to commit, else the reverse fk has nothing to point to
group = super(CreateGroupForm, self).save(commit=True)
group.student_set.add(*self.cleaned_data['students'])
return group
If you prefer not to remove the non-commit save option on the form, you can also override the form_valid method of the view:
class SelectGroup(CreateView):
# ...
def form_valid(self, form):
self.object.student_set.add(*self.form.cleaned_data['students'])
return super(SelectGroup, self).form_valid(form)

Replace PrimaryKeyRelatedField with another field

I have models which consist in a User model and a Present one. A User can have multiple Present but a Present has a unique User:
My models.py is:
from django.db import models
from django.contrib.auth.models import User
class Present(models.Model):
name = models.CharField(max_length=15)
price = models.FloatField()
link = models.CharField(max_length=15)
isAlreadyBought = models.BooleanField()
user = models.ForeignKey(User, related_name='presents', on_delete=models.CASCADE)
My serializers.py are:
from django.contrib.auth.models import User, Group
from rest_framework import serializers
from blog.models import Present, Location
from django.contrib.auth.models import User
class UserSerializer(serializers.ModelSerializer):
presents = serializers.PrimaryKeyRelatedField(many=True, queryset=Present.objects.all(), required=False)
class Meta:
model = User
fields = ('username', 'password', 'email', 'presents')
def create(self, validated_data):
user = super().create(validated_data)
if 'password' in validated_data:
user.set_password(validated_data['password'])
user.save()
return user
class PresentSerializer(serializers.ModelSerializer):
user = serializers.PrimaryKeyRelatedField(queryset=User.objects.all(), read_only=False, many=False)
class Meta:
model = Present
fields = ('name', 'link', 'price', 'isAlreadyBought', 'user')
def create(self, validated_data):
return Present.objects.create(**validated_data)
Currently, if I want to get the all the presents associate with a given User, I use the primary key (in views.py):
class PresentsOfUser(viewsets.ModelViewSet):
queryset = Present.objects.all().filter(user=33)
serializer_class = PresentSerializer
However, I would rather use the username field of the User instead of the primary key.
I have tried using a SlugRelatedField but I am not sure this is the right way to achieve my goal:
class PresentSerializer(serializers.ModelSerializer):
user = serializers.SlugRelatedField(queryset=User.objects.all(), slug_field='username', read_only=False, many=False)
class Meta:
model = Present
fields = ('name', 'link', 'price', 'isAlreadyBought', 'user')
def create(self, validated_data):
return Present.objects.create(**validated_data)
And with this modification, I now use the following View to get the user 'Marcel' whose id is 33:
class PresentsOfUser(viewsets.ModelViewSet):
queryset = Present.objects.all().filter(user='Marcel')
serializer_class = PresentSerializer
But in this case, I get:
ValueError: invalid literal for int() with base 10: 'Marcel'
But if I replace user='Marcel' by user=33 (as previously), I get:
[{"name":"Nintendo","link":"fake_link","price":50.8,"isAlreadyBought":true,"user":"Marcel"},{"name":"Gamecube","link":"fake_link","price":50.8,"isAlreadyBought":true,"user":"Marcel"}]
where the user field is now the username and not the user's id.
However, I do not understand why filtering with user='Marcel' fails...

I ended up by overriding the get_querysetmethod while keeping the PrimaryKeyRelatedField in my serializer (with user__username='Marcel'as mishbah suggested):
class PresentsOfUser(viewsets.ModelViewSet):
serializer_class = PresentSerializer
def get_queryset(self):
"""
Optionally restricts the returned purchases to a given user,
by filtering against a `username` query parameter in the URL.
"""
queryset = Present.objects.all()
username = self.kwargs['user']
if username is not None:
queryset = queryset.filter(user__username=username)
if len(queryset) == 0:
raise Http404
return queryset
It also works when replacing PrimaryKeyRelatedField by SlugRelatedField:
user = serializers.SlugRelatedField(queryset=User.objects.all(), slug_field='username', read_only=False, many=False)
and adding to_field='username'in the ForeignKey of my Present model:
user = models.ForeignKey(User, related_name='presents', to_field='username', on_delete=models.CASCADE)

I think your issue is w/ this line:
queryset = Present.objects.all().filter(user='Marcel')
With the assumption Marcel is username with pk => 33
You can't filter using a string, instead something like this:
queryset = Present.objects.all().filter(user__username='Marcel')
Hope that helps.

Cannot post entry specifying specific id if the id is specified as ForeignKey in Django

I have two models, Book and ReadBy as specified in models.py:
class Book(models.Model):
created = models.DateTimeField(auto_now_add=True)
owner = models.ForeignKey(MyUser)
class ReadBy(models.Model):
created = models.DateTimeField(auto_now_add=True)
owner = models.ForeignKey(MyUser)
book = models.ForeignKey(Book)
views.py:
class BookViewSet(viewsets.ModelViewSet):
queryset = Book.objects.all()
serializer_class = BookSerializer
permission_classes = (permissions.IsAuthenticatedOrReadOnly,)
def pre_save(self, obj):
obj.owner = self.request.user
class ReadByViewSet(viewsets.ModelViewSet):
queryset = ReadBy.objects.all()
serializer_class = ReadBySerializer
permission_classes = (permissions.IsAuthenticatedOrReadOnly,)
def pre_save(self, obj):
obj.owner = self.request.user
serializers.py:
class BookSerializer(serializers.ModelSerializer):
readby = serializers.SerializerMethodField('get_ready_by')
def get_read_by(self, obj):
user = self.context['request'].user
book = obj
return ReadBy.objects.filter(book=book, owner=user).exists()
class Meta:
model = Book
fields = ('id', 'created', 'owner', 'readby')
class ReadBySerializer(serializers.ModelSerializer):
owner = serializers.Field(source='owner.id')
book = serializers.Field(source='book.id')
class Meta:
model = ReadBy
fields = ('id', 'created', 'owner', 'book')
Book is a ForeignKey in ReadBy. The reason for this is that I want to see if the book has been read by defining the readby field in BookSerializer to true or false.
Now when I try to POST a ReadBy item I cannot explicitly set the book_id, even if I try do I still get the same error:
"Column 'book_id' cannot be null"
What I need to know is how I can explicitly specify book_id to be able to "read" a book.
Thanks.

class ReadBy(models.Model):
... snip ...
book = models.ForeignKey(Book, null=True, blank=True)

OK I solved this.
I forgot to define the book field in the ReadBySerializer as PrimaryKeyRelatedField:
book = serializers.PrimaryKeyRelatedField(source='book.id')
In fact it seems like I can remove this line altogether since PrimaryKeyRelatedField is default if nothing is specified.