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update_or_create in my django rest framework api work wrong

My problem in GIF
Instead of updating the user's rating DRF creating new.
Maybe i made a mistake in serializer?
I wrote documentation but i dont kwon where i wrong.
My code:
views.py:
class CreateReviewView(APIView):
def post(self, request):
review = CreateReviewSerializer(data= request.data)
if review.is_valid():
review.save()
return Response(status=201)
class CreateRatingView(APIView):
def get_user(self, request):
user= request.user
if user =="AnonymousUser":
return "noname in CreateRaringView"
return user
def post(self, request):
serializer = CreateRatingSerializer(data=request.data)
if serializer.is_valid(raise_exception=True):
serializer.save(user=self.get_user(request))
return Response(status=201)
else:
return Response(status=400)
serializers.py:
class Meta:
model = Rating
fields = ('star','movie')
def new(self,validated_data):
rating = Rating.objects.update_or_create(
user= validated_data.get('user',None),
movie= validated_data.get('movie',None),
defaults={'start': validated_data.get("star")}
)
return rating
models.py:
class Rating(models.Model):
"""Рейтинг"""
user = models.ForeignKey(User,on_delete=models.CASCADE,verbose_name="Пользователь",related_name='user')
star = models.ForeignKey(RatingStar, on_delete=models.CASCADE, verbose_name="Звезда",related_name="star")
movie = models.ForeignKey(Movie, on_delete=models.CASCADE, verbose_name="Фильм",related_name="movie")
def __str__(self):
return f"{self.star} - {self.movie}"
class Meta:
#unique_together = ['user','movie','star']
verbose_name = "Рейтинг"
verbose_name_plural = "Рейтинги"

According to documentation, Calling .save() will either create a new instance, or update an existing instance, depending on if an existing instance was passed when instantiating the serializer class:
# .save() will create a new instance.
serializer = CommentSerializer(data=data)
# .save() will update the existing `comment` instance.
serializer = CommentSerializer(comment, data=data)
In your case you are only passing new data and missing existing instance.
def post(self, request):
serializer = CreateRatingSerializer(data=request.data)

I renamed def new(self,validated_data): to def create(self,validated_data): in serializers.py and all started working. >.<

Django: Update a specific field with a GET instead of a PATCH

Context
For a specific use case I need to be able to update a single field of my Visitor model using a GET request instead of a PATCH request.
My relevant Visitor model looks like this:
# models.py
class Visitor(models.Model):
visitor_uuid = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False, db_index=True)
customers = models.ForeignKey(Customer, on_delete=models.CASCADE, related_name='customer_visitors')
audiences = models.ManyToManyField(Audience, related_name='audience_visitors')
cid = models.CharField(max_length=255, unique=True)
uid = models.CharField(max_length=255)
cup = JSONField(null=True)
def __str__(self):
return self.cid
class Meta:
db_table = 'visitor'
I am using a straightforward serializer like this:
# serializers.py
class VisitorSerializer(serializers.ModelSerializer):
class Meta:
model = Visitor
fields = ('customers', 'cid', 'uid', 'cup')
I am able to update just the cup field for a specific Visitor which is looked up using the unique cid field with a PATCH like this:
# views.py
class VisitorViewSet(viewsets.ModelViewSet):
serializer_class = VisitorSerializer
queryset = Visitor.objects.all()
lookup_field = 'cid'
def list(self, request, *args, **kwargs):
instance = self.get_object()
serializer = self.serializer_class(instance, data=request.data, partial=True)
serializer.is_valid(raise_exception=True)
serializer.save()
return Response(serializer.data)
Problem
The problem is that I am unable to update the cup field of a Visitor based on a given unique cid field using a GET request.
What I tried
As this answer by Uri Shalit suggested, I tried to override get_serializer() inside my VisitorViewSet and tried to use it in list() like this:
# views.py
class VisitorViewSet(viewsets.ModelViewSet):
serializer_class = VisitorSerializer
queryset = Visitor.objects.all()
lookup_field = 'cid'
def get_serializer(self, *args, **kwargs):
kwargs['partial'] = True
return super(VisitorViewSet, self).get_serializer(*args, **kwargs)
def list(self, request, *args, **kwargs):
instance = self.get_object()
serializer = self.get_serializer(instance, data=request.data, partial=True)
serializer.is_valid(raise_exception=True)
serializer.save()
return Response(serializer.data)
However, updating just the cup field of a specific Visitor based on the cid field works with a PATCH request but does not update said field with a GET request. There is no error either.
Expected behaviour
Making a GET request which contains cid to identify a Visitor and cup with data that needs to be updated for the given Visitor. I know it breaks REST principles but for this use case I need to do this partial update using a GET request instead of a PATCH request.
Any help or pointers in the right direction would be much appreciated!

Add a classmethod in your model.
class Visitor(models.Model):
visitor_uuid = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False, db_index=True)
customers = models.ForeignKey(Customer, on_delete=models.CASCADE, related_name='customer_visitors')
audiences = models.ManyToManyField(Audience, related_name='audience_visitors')
cid = models.CharField(max_length=255, unique=True)
uid = models.CharField(max_length=255)
cup = JSONField(null=True)
def __str__(self):
return self.cid
class Meta:
db_table = 'visitor'
#classmethod
def update_cup(cls, cid, cup_new):
instance = cls.objects.get(cid=cid)
instance.cup = new_cup
instance.save()
In ModelViewSet override the get_queryset method, see below:
IDK how u calc new_cup I guess u get it as a queryparam
def get_queryset(self):
queryset = Visitor.objects.all()
cup_new = self.request.query_params.get('cup_new', None)
cid = self.request.query_params.get('cid', None)
[obj.update_cup(obj.cid, cup_new) for obj in queryset if obj.cid == cid]
return queryset

I recommend using an api_view to accomplish what you want. api_view is an annotation provided by the rest framework so it should be available already in your case.
#api_view(["GET"])
def update_function(request):
query_params = request.GET # Getting the parameters from request
cid = query_params["cid"]
cup = query_params["cup"]
visitor = Visitor.objects.get(cid = cid)
visitor["cup"] = cup
serializer = VisitorSerializer(data = visitor, partial=True)
if serializer.is_valid():
serializer.save()
else:
print(serializer.errors)
However I am not sure about the syntax but the approch is sufficient for your problem.
Make sure to add the function to urls.py and have a look to the documentation to get better information than mine Api Views. But dont expect it to have information about you specific problem. In your case you have to understand the api_view concept and adapt it for your needs.

I think I don't understand the problem fully. Why can't you simply override the method get_object() in your view and do custom logic in it to update the object?
def get_object(self):
obj = super().get_object()
serializer = self.get_serializer(obj, data=self.request.data)
serializer.is_valid(raise_exception=True)
serializer.save()
return obj

Django DRF change serializer data with CreateListModelMixin

I have this class view, but I am unable to modify the serializer data to insert more data (which is needed and needs to be populated automatically).
Because I am creating many instances at once, the serializer is based on kwargs['many'] = True.
Any idea on how I can add another field to each serializer data?
Thanks,
:
class ReservedServiceView(CreateListModelMixin, ModelViewSet):
queryset = ReservedService.objects.all()
serializer_class = ReservedServiceSerializer
authentication_classes = (authentication.TokenAuthentication,)
def perform_create(self, serializer):
# Create an event that is a Reflection of the Reserved Service
serializer_data = self.request.data
for reserved_service in serializer_data:
print("--------",reserved_service, flush=True)
service_id = reserved_service['original_service']
original_service = Service.objects.get(pk=service_id)
calendar_event = CalendarEvent()
calendar_event.name = original_service.name
calendar_event.description = original_service.description
calendar_event.date = reserved_service['date']
calendar_event.type_id = 1
calendar_event.start_time = reserved_service['start_time']
calendar_event.end_time = reserved_service['end_time']
calendar_event.location_id = original_service.location.id
calendar_event.save()
reserved_service['associated_event'] = calendar_event.id
print("**********1", serializer_data)
print("**********2", self.request.data)
serializer.save()
Based in:
class CreateListModelMixin(object):
def get_serializer(self, *args, **kwargs):
""" if an array is passed, set serializer to many """
if isinstance(kwargs.get('data', {}), list):
kwargs['many'] = True
return super(CreateListModelMixin, self).get_serializer(*args, **kwargs)

I am not able to properly get your question, but if your question is that you are not getting the extra fields which you added to the serializer in the response of the view, then here is the answer for it.
The response of this view is returned by create method of CreateModelMixin which passes serializer.data to the data param of Response. You cannot update serializer.data because it is an immutable object. So, to solve this you will have to override the create method as follows:
class ReservedServiceView(CreateListModelMixin, ModelViewSet):
queryset = ReservedService.objects.all()
serializer_class = ReservedServiceSerializer
authentication_classes = (authentication.TokenAuthentication,)
def create(self, request, *args, **kwargs):
serializer = self.get_serializer(data=request.data)
serializer.is_valid(raise_exception=True)
my_data = {}.update(serializer.validated_data)
# Now you can work over the my_data and add extra fields to it and save it
# and instead of passing serializer.data we pass my_data to Response class
headers = self.get_success_headers(serializer.data)
return Response(my_data, status=status.HTTP_201_CREATED, headers=headers)

How to set user_id field using JWT in DRF

I want to set user_id field using JWT token and store in database table when new reservation is created. there can be single or multiple reservation request.
whenever user create reservation i want to store there user_id in our table. currently there is no foreign key associated with it. it is simply an integer field.
I am able to fetch user_id from JWT.but its not updating in database
I know this question had been asked previously i tried all the answer of previous post but its not working for me. i dont know why
model.py
class reservations(models.Model):
pet_id=models.IntegerField()
user_id=models.IntegerField(default=0)
location=models.PositiveSmallIntegerField()
arrival=models.DateTimeField()
depature=models.DateTimeField()
comments=models.TextField(max_length=200)
view.py
class requestReservation(CreateAPIView):
serializer_class = requestReservationSerailizer
permission_classes = [IsAuthenticated]
def create(self, request, *args, **kwargs):
serializer = requestReservationSerailizer(data=request.data,context={'user_id': request.user.id}, many=True)
if not serializer.is_valid(raise_exception=False):
return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
self.perform_create(serializer)
headers = self.get_success_headers(serializer.data)
return Response({"message":"Success","status_message":"Reservation Created Successfully"},status=status.HTTP_200_OK)
serializer.py
class requestReservationSerailizer(ModelSerializer):
user_id = SerializerMethodField('set_user_id')
class Meta:
model=reservations
fields = [
'pet_id',
'user_id',
'location',
'arrival',
'depature',
'comments',
]
def set_user_id(self, obj):
obj.user_id = self.context.get("user_id")
return obj.user_id
currently it is simply storing user_id as 0 which is default set in model.

SerializerMethodField is read-only by default, here's a quick look at the source code:
def __init__(self, method_name=None, **kwargs):
self.method_name = method_name
kwargs['source'] = '*'
kwargs['read_only'] = True
super(SerializerMethodField, self).__init__(**kwargs)
Assuming you want to read and write into this field; remove the SerializerMethodField overriding from the serializer declaration; and set the user_id in your view
class requestReservationSerailizer(ModelSerializer):
class Meta:
model=reservations
fields = [
'pet_id',
'user_id',
'location',
'arrival',
'depature',
'comments',
]
def create(self, request, *args, **kwargs):
data = request.data.copy()
for datum in data:
datum['user_id'] = request.user.id
serializer = requestReservationSerailizer(data=data, many=True)
if not serializer.is_valid(raise_exception=False):
return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
self.perform_create(serializer)
headers = self.get_success_headers(serializer.data)
return Response({"message":"Success","status_message":"Reservation Created Successfully"},status=status.HTTP_200_OK)
Ofcourse; if you don't want your view to be doing this (and I'd agree with you here), then pass it in context (explicit) or use self.request.user.id and override validate_user_id
class requestReservationSerailizer(ModelSerializer):
class Meta:
model=reservations
fields = [
'pet_id',
'user_id',
'location',
'arrival',
'depature',
'comments',
]
def validate_user_id(self, value):
user_id = self.context.get('user_id', None) # Assuming you continue to pass it in context
if user_id is None:
# Handle error
return user_id
# You can also do this; might raise an AttributeError if the user is not authenticated:
# return self.request.user.id

How to update multiple records at once (bulk update) in django API

I need to update categories in many Article in one request.
In ArticleViewSet I have:
def get_serializer_class(self):
if self.action in ['partial_update', 'update']:
return ArticlePostSerializer
return ArticleSerializer
So ArticlePostSerializer need to be changed.
This is my serializers code:
class ArticleShortCategorySerializer(serializers.ModelSerializer):
class Meta:
model = Category
fields = 'id', 'name'
class ArticleSerializer(serializers.ModelSerializer):
categories = serializers.SerializerMethodField()
def get_categories(self, obj):
return ArticleShortCategorySerializer(obj.categories, many=True).data
class Meta:
model = Article
read_only_fields = 'id'
fields = ('categories', 'text') + read_only_fields
class ArticlePostSerializer(serializers.ModelSerializer):
class Meta:
model = Article
fields = 'id', 'categories', 'text'
I tried to add:
class ArticlePostListSerializer(serializers.ListSerializer):
and
class Meta:
list_serializer_class = ArticlePostListSerializer
But it doen't work.
How to change this code to do multiple update.
My json request
{
[id: 90, categories: [10,12,14]],
[id: 93, categories: [10,12,14]],
[id: 95, categories: [10,12,14]]
}

Here is sample of CreateMixins OR UpdateMixins you requested.
======================= VIEW ================================
class OrderCreate(mixins.CreateModelMixin,viewsets.GenericViewSet):
pagination_class = None
def get_queryset(self):
return []
def get_serializer_class(self):
return serializers.OrderSerializer
======================= Serializer =============================
class OrderDetailSerializer(serializers.ModelSerializer):
class Meta:
model = crm_models.OrderDetail
fields = (
'product',
'quantity',
'rate_per_unit',
'order_quantity'
)
class OrderSerializer(serializers.ModelSerializer):
order_details = OrderDetailSerializer(many = True)
class Meta:
model = crm_models.OrderMaster
fields = (
'order',
'invoice_number',
'client',
'beat_check',
'target_customer',
'order_editor_client_employee',
'order_marked',
'order_saved',
'edit_marked',
'edit_saved',
'adhoc',
'order_details'
)
def create(self, validated_data,*args,**kwargs):
ordersdetails_data = validated_data.pop('order_details')
user = None
request = self.context.get("request")
if request and hasattr(request, "user"):
user = request.user
validated_data['client'] = user.client
validated_data['order_editor_client_employee'] = user
validated_data['adhoc'] = validated_data['adhoc'] if 'adhoc' in validated_data else False
orderObj = super(OrderSerializer, self).create(validated_data,*args,**kwargs)
orderdetails = []
for details in ordersdetails_data:
orderdetails.append(crm_models.OrderDetail(
product= details['product'],
quantity = details['quantity'],
rate_per_unit = details['rate_per_unit'],
order_quantity = details['order_quantity'],
order = orderObj
))
crm_models.OrderDetail.objects.bulk_create(orderdetails)
return orderObj
In Update view function name would be changed to update, you can find more documentation http://www.django-rest-framework.org/api-guide/generic-views/#createmodelmixin

I found K. Moe's answer to this question: Django Rest Framework POST Update if existing or create much easier to understand and implement. You only need to add a create method in the serializer and use mixins.CreateModelMixin, generics.GenericAPIView in the view. Then you can use a POST request, instead of PUT/PATCH. It allows to create AND update data stored in your database. My code for the view:
class ZipCodeList(mixins.CreateModelMixin, generics.GenericAPIView):
def post(self, request, format=None):
is_many = isinstance(request.data, list)
if is_many:
serializer = ZipCodeSerializer(data=request.data, many=True)
if serializer.is_valid():
serializer.save()
return Response(serializer.data, status=status.HTTP_201_CREATED)
return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
else:
serializer = ZipCodeSerializer(data=request.data)
if serializer.is_valid():
serializer.save()
return Response(serializer.data, status=status.HTTP_201_CREATED)
return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)

#Greg Holst, why so much duplication? Why not:
class ZipCodeList(mixins.CreateModelMixin, generics.GenericAPIView):
def post(self, request, format=None):
serializer = ZipCodeSerializer(data=request.data, many=isinstance(request.data, list))
if serializer.is_valid():
serializer.save()
return Response(serializer.data, status=status.HTTP_201_CREATED)
return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
Anyway, that only worked for me for creating new objects, didn't work to create-or-update in one sweep (it kept telling me these objects already exist), so this is what I did:
class ContributorSyncListAPIView(ListAPIView):
permission_classes = (isSuperUserPermission,)
allowed_methods = ("GET", "PUT")
lookup_field = "airtable_id"
serializer_class = ContributorSyncSerializer # Doesn't get used in Put, just in Get.
model = Contributor
def get_queryset(self):
return self.model.objects.all()
def put(self, request, format=None):
objects = list(request.data)
# objects is a list of OrderedDicts
try:
for o in objects:
try:
instance = self.model.objects.get(
**{self.lookup_field: o.get(self.lookup_field)}
)
for key, value in o.items():
setattr(instance, key, value)
except self.model.DoesNotExist:
instance = self.model(**o)
instance.save()
return Response(objects, status=status.HTTP_200_OK)
except Exception as e:
return Response({"detail": str(e)}, status=status.HTTP_400_BAD_REQUEST)
Note my code above is very light on validation just because it was for a process of syncing models from one environment to another by a superuser, different environments with an identical codebase; so the assumption was the data had already been validated when the data was entered into the first environment. For any other purpose you'd want to validate more. But this is what I had to do to handle a list of objects that may need to be created or updating, on an object-by-object basis.