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Django Rest Framework how do I get the id I use in the URL

I have this serializer and I use it to get post detail of a post belonging to a user. The owner of the post is not the user that is currently logged in. I want to check if the post is bookmarked by the currently logged in user. The currently logged in user's id is passed in the request but I cannot find it in this context.
Here is the serializer:
class UserPostSerializer(serializers.ModelSerializer):
images = PostImageSerializer(many=True, read_only=True, required=False)
profile = serializers.SerializerMethodField()
bookmarked = serializers.SerializerMethodField()
class Meta:
model = Post
fields = [
"id",
"category",
"body",
"images",
"video",
"profile",
"published",
"bookmarked",
"created_at",
"updated_at",
]
depth=1
def get_profile(self, obj):
profile_obj = Profile.objects.get(id=obj.user.profile.id)
profile = ShortProfileSerializer(profile_obj)
return profile.data
def get_bookmarked(self, obj):
breakpoint()
bookmark = Bookmark.objects.filter(owner=obj.user.id, post=obj.id,marktype='post')
if bookmark:
return True
else:
return False
The problem is obj.user.id is the owner of the post. I need the logged in user whose id is passed in the url. Here is the model for the bookmark:
class Bookmark(models.Model):
marktype = models.CharField(max_length=50)
post = models.OneToOneField(Post, on_delete=models.CASCADE, null=True, blank=True)
owner = models.ForeignKey(User, on_delete=models.CASCADE)
created_at = models.DateTimeField(auto_now_add=True, verbose_name="created at")
updated_at = models.DateTimeField(auto_now=True, verbose_name="updated at")
class Meta:
verbose_name = "bookmark"
verbose_name_plural = "bookmarks"
ordering = ["created_at"]
db_table = "bookmarks"
def __str__(self):
return "{}'s bookmark".format(self.owner.username)
and here is the URL:
path("posts/<int:user>/home/", HomeView.as_view(), name="home"),
This self.context['request'].user returns the owner of the post and not the logged in user.
How do I get the id of the currently logged in user or the user whose id I pass in the URL please?

Maybe do you can use filters to the Viewset:
urls.py
path("posts/home/", HomeView.as_view(), name="home")
viewsets.py
from rest_framework import viewsets
from .models import Post
from .serializers import, UserPostSerializer
from .filters import OwnerFilter
class HomeView(viewsets.ModelViewSet):
queryset = Post.objects.all()
serializer_class = UserPostSerializer
filter_backends = (OwnerFilter,)
filters.py
from rest_framework.filters import BaseFilterBackend
class OwnerFilter(BaseFilterBackend):
def filter_queryset(self, request, queryset, view):
owner = request.query_params.get('owner', None)
if not owner:
return queryset.all()
else:
try:
return queryset.filter(bookmarked__owner__id=owner)
except Exception:
return queryset.none()
Running
Then access the URL:
/posts/home/?owner=OWNER_ID_HERE

Solved it and you can get any kwargs from the view that handles the request. In my case adding the following to the get_bookmarked function gives me the id I send in the URL:
loggeduser = self.context.get('view').kwargs.get('user')

How to fetch data by foreign key in Django serializers?

I'm stuck on fetching data with a related foreign key. I am doing some kind of validation in which the create method would be allowed depending on the requesterid to be POSTed.
This is my userTable model:
class userTable(models.Model):
userid = models.UUIDField(primary_key=True, default = uuid.uuid4, editable=False)
username = models.CharField(max_length=50, null=False, unique=True)
userroleid = models.ForeignKey(roleTable, on_delete=models.CASCADE)
def __str__(self):
return self.username
Another model is the requestTable
class requestTable(models.Model):
rid = models.AutoField(primary_key=True)
requesterid = models.ForeignKey(userTable, on_delete=models.CASCADE)
(...)
This is my serializer:
class RequestCreateSerializer(serializers.ModelSerializer):
parts=PartSerializer(many=True)
class Meta:
model = requestTable
fields = ['rid','requesterid', (...)]
def create(self, instance, validated_data):
if instance.requesterid.userroleid == 3: #how can i fetch my `requesterid` data?
parts_data = validated_data.pop('parts')
request = requestTable.objects.create(**validated_data)
for part_data in parts_data:
partsTable.objects.create(request=request, **part_data)
return request
raise ValidationError("Sorry! Your role has no permission to create a request.")
Also, I'm quite confused if I should do validation in serializers, or views. If I do it in views, it just throws the ValidationError, and it doesn't seem to enter the if condition.
For reference, here's my views:
class RequestListCreateView(ListCreateAPIView):
queryset = requestTable.objects.all()
serializer_class = RequestCreateSerializer
def create(self, request, *args, **kwargs):
if request.data.get('requesterid__userroleid') == '3':
write_serializer = RequestCreateSerializer(data=request.data)
write_serializer.is_valid(raise_exception=True)
self.perform_create(write_serializer)
headers = self.get_success_headers(write_serializer.data)
return Response({"Request ID": write_serializer.instance.requestid, "Parts ID": [p.partsid for p in write_serializer.instance.parts.all()]},headers=headers)
raise ValidationError("Sorry! Your role has no permission to create a request.")
Hope someone can help me!

UserCheckout matching query does not exist

I'm trying to display all orders matching each logged in user, I dont understand why it gives me issues when trying to filter for users as it gives me that UserCheckout does not have any matching queries:
orders/views.py
class OrderList(LoginRequiredMixin, ListView):
queryset = Order.objects.all()
def get_queryset(self):
user_check_id = self.request.user.id
user_checkout = UserCheckout.objects.get(id=user_check_id)
return super(OrderList, self).get_queryset().filter(user=user_checkout)
orders/mixins.py
class LoginRequiredMixin(object):
#method_decorator(login_required)
def dispatch(self, request, *args, **kwargs):
return super(LoginRequiredMixin, self).dispatch(request,*args, **kwargs)
orders/models.py
class UserCheckout(models.Model):
user = models.OneToOneField(settings.AUTH_USER_MODEL, null=True, blank=True, on_delete = models.CASCADE) # not required as to allow guests to checkout too
email = models.EmailField(unique=True) # required, unique as if there the guest already has an authentication just one email needed
def __str__(self):
return self.email
class Order(models.Model):
status = models.CharField(max_length=120, choices=ORDER_STATUS_CHOICES, default='created')
cart = models.ForeignKey(Cart, on_delete=models.CASCADE)
user = models.ForeignKey(UserCheckout, null=True, on_delete=models.CASCADE)
billing_address = models.ForeignKey(UserAddress, related_name='billing_address', null=True,on_delete=models.CASCADE)
shipping_address = models.ForeignKey(UserAddress, related_name='shipping_address', null=True, on_delete=models.CASCADE)
shipping_total_price = models.DecimalField(max_digits=50, decimal_places=2, default=5.99)
order_total = models.DecimalField(max_digits=50, decimal_places=2)
def __str__(self):
return str(self.cart.id)
Error it gives me:
DoesNotExist at /orders/
UserCheckout matching query does not exist.

You are getting an error because you are trying to use the User's primary key (id) as the UserCheckout's primary key i.e. the lines:
user_check_id = self.request.user.id
user_checkout = UserCheckout.objects.get(id=user_check_id)
Change these lines to:
user = self.request.user
user_checkout = UserCheckout.objects.get(user=user)
Also this can throw an Exception if a UserCheckout instance doesn't exist you can catch that using try-except or use django's shortcut function get_object_or_404:
from django.shortcuts import get_object_or_404
user_checkout = get_object_or_404(UserCheckout, user=user)

django ValueError Cannot query "abcd#gmail.com": Must be "object" instance

i am trying to make an app for student but i'm getting this error,
as you can see for convenient i wanted to use like that one i showed bellow but it doesn't work, should i keep using like before? or i could use like that ? what would be best way ?
ValueError at /student/program_structure/
Cannot query "abcd#gmail.com": Must be "Student" instance.
thank you so much :)
models.py
class Student(models.Model):
user = models.ForeignKey(
settings.AUTH_USER_MODEL, on_delete=models.CASCADE, null=True)
status = models.CharField(max_length=10, choices=STATUS, default='active')
class Program(models.Model):
#everything was fine when used
user = models.ForeignKey(
settings.AUTH_USER_MODEL, on_delete=models.CASCADE, null=True) #this one
#but when using this one i started getting this error from views.py
user = models.ForeignKey(
Student, on_delete=models.SET_NULL, null=True)
name = models.CharField(max_length=200, unique=True)
prefix = models.CharField(max_length=20)
class Course(models.Model):
user = models.ForeignKey(Student, on_delete=models.SET_NULL, null=True)
name = models.CharField(max_length=200, unique=True)
prefix = models.CharField(max_length=20)
code = models.CharField(max_length=20)
subject = models.ManyToManyField('Subject', related_name='subject_list',
blank=True)
views.py
class Program_structure(generic.View):
def get(self, *args, **kwargs):
profile = get_object_or_404(Student, user=self.request.user)
program_structure = Course.objects.filter(student=profile)
# program_structure =
Course.objects.filter(student__user=self.request.user)
credit = Course.objects.filter(student__user=self.request.user).
annotate(total_no=Sum('subject__credit'))
total_credit = self.request.user.course_set.aggregate(
total_credit=Sum('subject__credit')
)['total_credit'] or 0
context = {
'test':program_structure,
'credit':credit,
'profile':profile,
'total_credit' : total_credit
}
return render(self.request, 'program_structure.html', context)

The user field of the Course refers to the Student object, not a User object, so you can not user request.user for this.
You can however query for a Course where the user is a Student where the user is request.user with:
class Program_structure(generic.View):
def get(self, *args, **kwargs):
profile = Student.objects.all()
program_structure = Course.objects.filter(user__user=self.request.user)
context = {
'test':program_structure,
'profile':profile,
}
return render(self.request, 'program_structure.html', context)
You probably also want to set profile to the Student object of the user. In that case, you can reuse the profile when you filter the Courses:
from django.shortcuts import get_object_or_404
class Program_structure(generic.View):
def get(self, *args, **kwargs):
profile = get_object_or_404(Student, user=request.user)
program_structure = Course.objects.filter(user=profile)
context = {
'test':program_structure,
'profile':profile,
}
return render(self.request, 'program_structure.html', context)
It might also be better to rename the user field to student:
class Course(models.Model):
student = models.ForeignKey(
Student,
on_delete=models.SET_NULL,
null=True
)
# …
since that makes it clear that this is a Student, not a User. In that case you filter with:
from django.shortcuts import get_object_or_404
class Program_structure(generic.View):
def get(self, *args, **kwargs):
profile = get_object_or_404(Student, user=request.user)
program_structure = Course.objects.filter(student=profile)
context = {
'test':program_structure,
'profile':profile,
}
return render(self.request, 'program_structure.html', context)

Django rest framework if serializer returns empty

I have am implementing a follower and followers system in my drf api.
My relationship model and serializer:
models.py
class Relationship(models.Model):
user = models.ForeignKey(User, related_name="primary_user", null=True, blank=True)
related_user = models.ForeignKey(User, related_name="related_user", null=True, blank=True)
incoming_status = models.CharField(max_length=40, choices=RELATIONSHIP_CHOICE, default=RELATIONSHIP_CHOICE[0])
def __str__(self):
return self.user.username + " " + self.incoming_status + " " + self.related_user.username
serializers.py
class RelationshipSerializer(serializers.ModelSerializer):
outgoing_status = serializers.SerializerMethodField()
class Meta:
model = models.Relationship
fields = (
'user',
'related_user',
'incoming_status',
'outgoing_status',
)
def get_outgoing_status(self, obj):
related_user = obj.related_user
user = obj.user
try:
query = models.Relationship.objects.get(user=related_user, related_user=user)
user_id = query.incoming_status
except models.Relationship.DoesNotExist:
user_id = "none"
return user_id
views.py
class UserViewSet(viewsets.ModelViewSet):
queryset = models.User.objects.all()
serializer_class = serializers.UserSerializer
#detail_route(methods=['get'], url_path='relationship/(?P<related_pk>\d+)')
def relationship(self, request, pk, related_pk=None):
user = self.get_object()
query = models.Relationship.objects.filter(user=user)&\
models.Relationship.objects.filter(related_user__pk=related_pk)
serializer = serializers.RelationshipSerializer(query, many=True)
return Response(serializer.data)
Incoming status is your relationship to the user and outgoing status is the users relationship to you to so for example this can return
[
{
"user": 2,
"related_user": 1,
"incoming_status": "follows",
"outgoing_status": "none"
}
]
This means you follow the user and the user doesn't follow you back
When you follow a user my code works fine because it returns "incoming_status": "follows" and it then checks for the outgoing status in the serializers. However when the:
query = models.Relationship.objects.filter(user=user) &
models.Relationship.objects.filter(related_user__pk=related_pk)
query in views.py returns null the meaning that the incoming status is none the serializer outputs [] because the query is empty. How do I make incoming_status = "none" if the query is empty?
Thanks in advance