Unable to save with two models id field - django-rest-framework

Groom can like Bride, and Bride can like Groom. These two are different models in Likes Model.
I'm using the view set. Able to save individual model data but when I save Likes DRF throws field required error. Please suggest how to do better handling of many to many relationship handling between two models.
I also tried with ForeignKey relation in the models. The from bride/groom would be enforced with logged-in user id that is register bride/groom id (pk).
Models
class RegisterBride(models.Model):
'''Register Bride/Female profiles.'''
fname = models.CharField(max_length=200)
lname = models.CharField(max_length=200)
mobile = models.IntegerField(default=None)
gender = models.CharField(max_length=30, default='Female')
age = models.PositiveIntegerField(default=None, validators=[ MinValueValidator(18), MaxValueValidator(100)])
bride_account_status = models.BooleanField(default=False)
def __str__(self):
return self.fname + ' '+self.lname
class RegisterGroom(models.Model):
fname = models.CharField(max_length=200)
lname = models.CharField(max_length=200)
mobile = models.IntegerField(default=None)
gender = models.CharField(max_length=30, default='Male')
age = models.PositiveIntegerField(default=None, validators=[ MinValueValidator(18), MaxValueValidator(100)])
groom_account_status = models.BooleanField(default=False)
def __str__(self):
return self.fname + ' '+self.lname
class Likes(models.Model):
bride_profile = models.ManyToManyField(RegisterBride, related_name='bride_profile')
groom_profile = models.ManyToManyField(RegisterGroom, related_name='groom_profile')
likes = models.BooleanField(default=False)
created_date = models.DateField(auto_now_add=True)
Views
class RegisterGroomProfileViewSet(viewsets.ModelViewSet):
queryset = RegisterGroom.objects.all()
serializer_class = RegisterGroomSerializer
class RegisterBrideProfileViewSet(viewsets.ModelViewSet):
queryset = RegisterBride.objects.all()
serializer_class = RegisterBrideSerializer
class LikesViewSet(viewsets.ModelViewSet):
queryset = Likes.objects.all()
serializer_class = LikesSerializer
Serializers
class RegisterGroomSerializer(serializers.ModelSerializer):
class Meta:
model = RegisterGroom
fields = '__all__'
class RegisterBrideSerializer(serializers.ModelSerializer):
class Meta:
model = RegisterBride
fields = '__all__'
class LikesSerializer(serializers.ModelSerializer):
groom_profile_s = RegisterGroomSerializer(many=True, required=True)
bride_profile_s = RegisterBrideSerializer(many=True, required=True)
class Meta:
model = Likes
fields = '__all__'
extra_kwargs = {'likes': {'required': True}}
def create(self, data):
if data['bride_profile'] == data['groom_profile']:
raise ValidationError(detail='To Profile ID == From Profile ID. They should be different.')
return data
Request
Request URL: http://127.0.0.1:8000/likes/
Request Method: POST
Status Code: 400 Bad Request
{'likes': True,
'bride_profile': 1,
'groom_profile': 6}
Response
POST /likes/
HTTP 400 Bad Request
Allow: GET, POST, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept
{
"groom_profile_s": [
"This field is required."
],
"bride_profile_s": [
"This field is required."
]
}
Server Error:
..\rest_framework\pagination.py:200: UnorderedObjectListWarning: Pagination may yield inconsistent results with an unordered object_list: <class 'register.models.Likes'> QuerySet.
paginator = self.django_paginator_class(queryset, page_size)
Please suggest me.

Your request is not good : you put groom_profile_s and bride_profile_s as required but you do not send them in your request !
Request URL: http://127.0.0.1:8000/likes/
Request Method: POST
Status Code: 400 Bad Request
{'likes': True,
'groom_profile_s': [1],
'bride_profile_s': [6]}
After modifying your query, you should update your serializer.
class LikesSerializer(serializers.ModelSerializer):
groom_profile_s = RegisterGroomSerializer(many=True, required=True)
bride_profile_s = RegisterBrideSerializer(many=True, required=True)
class Meta:
model = Likes
fields = '__all__'
extra_kwargs = {'likes': {'required': True}}
def create(self, data):
if 'groom_profile_s' in data.keys():
groom_profile_s = validated_data.pop('groom_profile_s')
// Deal with your data here by creating the Like
// Same for bride_profile_s

Related

not a valid choice in django restframework serializer

i set my post model with choice and migrate model.
after that i create postserializer for create
and i run the server and post with data in postman for test,
but i got the 'is not a valid choice' err on serializer.
here is my model,
class Post(models.Model):
CATEGORY_CHOICES = (
('mc', 'MIRACLE'),
('hw', 'HOMEWORK')
)
title = models.CharField(max_length=50)
category = models.CharField(max_length=2, choices=CATEGORY_CHOICES)
content = models.TextField()
author = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE)
serializer,
class PostCreateSerializer(serializers.ModelSerializer):
class Meta:
model = Post
fields = '__all__'
view
class PostAPI(APIView):
def post(self, request):
data = {
'title' :request.data['title'],
'category':request.data['category'],
'content' :request.data['content'],
'author' :request.user.id
}
serializer = PostCreateSerializer(data=data)
if serializer.is_valid():
serializer.save()
else:
print(serializer.erros)
...
and request data (in Postman)
{
'title':'test_title',
'category':'HOMEWORK',
'content':'test_content'
}
result is
{'category': [ErrorDetail(string='"HOMEWORK" is not a valid choice.', code='invalid_choice')]}
i tried request with changing category 'HOMEWORK' to 'hw'
then it works
but i want request with large one
Your error on serialize level. Try this
readable_to_choice = {"HOMEWORK": "hw", "MIRACLE": "mc"}
data = {'title' :request.data['title'],
'category': readable_to_choice.get(request.data['category']),
'content' :request.data['content'],
'author' :request.user.id}
serializer = PostCreateSerializer(data=data)
UPD: you should make your api func like this:
serializer = PostCreateSerializer(data=request.data)
serializer.is_valid(raise_exception=True)
print(serializer.data) # do logic with that data
and try to override to_internal_value method in your serializer. for example:
def to_internal_value(self, data):
readable_to_choice = {"HOMEWORK": "hw", "MIRACLE": "mc"}
data["category"] = readable_to_choice.get(data["category"])
res = super().to_internal_value(data)
return res
I think this way is more accurate

TypeError: Field 'id' expected a number but got <class 'rest_framework.fields.CurrentUserDefault'>

Seems I need to apply a dot notation to CurrentUserDefault() object, tried .id but failed
class DotPrivateSerializer(serializers.ModelSerializer):
tag = serializers.SerializerMethodField()
def get_tag(self,obj):
queryset=TagPrivate.objects.filter(user=serializers.CurrentUserDefault) # <--TypeError
return TagPrivateSerializer(queryset).data
models.py
class DotPrivate(models.Model):
user = models.ForeignKey(
settings.AUTH_USER_MODEL,
on_delete=models.CASCADE
)
name = models.CharField(max_length=255)
description = models.TextField(max_length=350, blank=True)
lon = models.CharField(max_length=20)
lat = models.CharField(max_length=20)
rating = models.FloatField(validators=[MinValueValidator(0.0), MaxValueValidator(5.0)])
tag = models.ForeignKey('TagPrivate', on_delete=models.PROTECT)
in the following link in the first answer I found some solution but I do not completly understand it:
'CurrentUserDefault' object has no attribute 'user'
class TagPrivateSerializer(serializers.ModelSerializer):
class Meta:
model = TagPrivate
fields = ('id', 'name')
read_only_fields = ('id',)
You can not use CurrentUserDefault, this is just a value that the Django serializer will use for a default=… parameter, and then later swap for the request user.
You can fetch this from the request in the context, so:
class DotPrivateSerializer(serializers.ModelSerializer):
tag = serializers.SerializerMethodField()
def get_tag(self, obj):
queryset = TagPrivate.objects.filter(user=self.context['request'].user)
return TagPrivateSerializer(queryset).data
In the ModelViewSet, you will need to pass the user, so:
class DotPrivateViewSet(ModelViewSet):
queryset = # …
permission_classes = # …
serializer_class = DotPrivateSerializer
def get_serializer_context(self):
context = super().get_serializer_context()
context.update(request=self.request)
return context

I have to create serializer instance without data since i am not accepting any data from user

Here i am trying to create serializer instance without data argument because all i want to create a "Like" object which requires "user" object which i can get from request and "post" object that i am getting through querying Post model with pk but since i am not passing any data argument while deserializing it will throw an error.
So how can create instance without passing data argument or do i have to change my code and add data argument?
class Like(models.Model):
post = models.ForeignKey(Post, on_delete=models.CASCADE, related_name="likes")
liked_by = models.ForeignKey(User, on_delete=models.RESTRICT, related_name = "liked_posts")
def __str__(self):
return "{0} liked by {1}".format(self.post.img, self.liked_by.username)
class LikeSerializer(serializers.ModelSerializer):
liked_by = UserSerializer(read_only=True)
class Meta:
model = Like
fields = ("id","post", "liked_by")
class AddLike(APIView):
permission_classes = [IsAuthenticated]
def post(self, request, pk):
post = Post.objects.get(pk=pk)
user = request.user
serializer = LikeSerializer()
if not serializer.is_valid():
return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
serializer.save(post=post, liked_by=user)
return Response(data= serializer.data, status=status.HTTP_201_CREATED)
I think you can set the post field as read_only in the LikeSerializer.
class LikeSerializer(serializers.ModelSerializer):
liked_by = UserSerializer(read_only=True)
class Meta:
model = Like
fields = ("id","post", "liked_by")
extra_kwargs = {
'post': { 'read_only': True }
}

How represent a many to many relationship with django rest framework using Hyperlinking

I have two models in a 'many to many' relationship Video and Genre. I want to represent them in my API using the Django Rest Framework and with Hyperlinking. I have tried using the the nested relationships solution that I have found over the internet but it brings me an error for the list viewss eg genres/ and videos/ as described below.
models.py
class VideoGenre(models.Model):
video = models.ForeignKey(Video, on_delete=models.CASCADE, related_name='genres')
genres = models.ForeignKey(Genre, on_delete=models.CASCADE, related_name='videos')
class Meta:
unique_together = ['video', 'genre']
class Video(models.Model):
genres = models.ManyToManyField(Genre, related_name="videos", blank=True, through='VideoGenre')
title = serializers.CharField(default=serializers.CurrentUserDefault())
class Genre(models.Model):
name = models.CharField(max_length=20)
descr = models.CharField(max_length=255)
serializers.py
class GenreSerializer(serializers.HyperlinkedModelSerializer):
videos = serializers.HyperlinkedIdentityField(many=True, view_name="video-detail")
class Meta:
model = ku_api_models.Genre
fields = "__all__"
class VideoSerializer(serializers.HyperlinkedModelSerializer):
genres = GenreSerializer(source='genre_set', many=True, read_only=True)
class Meta:
model = ku_api_models.Video
fields = "__all__"
class VideoGenreSerializer(serializers.HyperlinkedModelSerializer):
video = serializers.ReadOnlyField(source='video.id')
genre = serializers.ReadOnlyField(source='genre.id')
class Meta:
model = ku_api_models.VideoGenre
fields = "__all__"
unique_together = ['video', 'genre']
views.py
class VideoDetailView(RetrieveUpdateDestroyAPIView):
parser_classes = (MultiPartParser,)
serializer_class = VideoSerializer
queryset = Video.objects.all()
def perform_update(self, serializer):
serializer.save(owner=self.request.user)
class VideoListView(ListCreateAPIView):
parser_classes = (MultiPartParser,)
serializer_class = VideoSerializer
queryset = Video.objects.all()
def perform_create(self, serializer):
serializer.save(owner=self.request.user)
class GenreListView(ListCreateAPIView):
serializer_class = GenreSerializer
queryset = Genre.objects.all()
class GenreDetailtView(RetrieveUpdateDestroyAPIView):
serializer_class = GenreSerializer
queryset = Genre.objects.all()
urls.py
path('videos/', views.VideoListView.as_view(), name='video-list'),
path('videos/<int:pk>', views.VideoDetailView.as_view(), name='video-detail'),
path('genres/', views.GenreListView.as_view(), name="genre-list"),
path('genres/<int:pk>', views.GenreDetailtView.as_view(), name="genre-detail"),
I am getting below exception on the browsable API renderer
Exception Type: ProgrammingError at /api/genres/
Exception Value: relation "ku_api_videogenre" does not exist
LINE 1: ..._video"."owner_id" FROM "ku_api_video" INNER JOIN "ku_api_vi...
I have looked into these below links as referred above
django rest framework serializing many to many field
many to many relationship through an intermidiate model
serializing many to many field
... and tried them but getting the same/almost the same, only different is the relation name that "does not exist"
What am I missing? How to make it right? Thanks
I have found a way to this:
Changes will be in the serializers.py
serializers.py
class VideoSerializer(serializers.HyperlinkedModelSerializer):
genres = serializers.HyperlinkedRelatedField(many=True, read_only=False, view_name='genre-detail', queryset=ku_api_models.Genre.objects.all())
class Meta:
model = ku_api_models.Video
#fields = ('url', 'id', 'datetime_added', 'title', 'video_file', 'owner')
fields = "__all__"
def create(self, validated_data):
genres = validated_data.pop('genres', [])
video_instance = ku_api_models.Video.objects.create(**validated_data)
video_instance.genres.set(genres)
return video_instance
def update(self, instance, validated_data):
genres = validated_data.pop('genres', [])
instance.genres.set(genres)
instance.save()
return instance
class VideoGenreSerializer(serializers.HyperlinkedModelSerializer):
class Meta:
model = ku_api_models.VideoGenre
fields = "__all__"
class GenreSerializer(serializers.HyperlinkedModelSerializer):
class Meta:
model = ku_api_models.Genre
fields = "__all__"
Source: Docs: intermediary-manytomany

How to restrict fields when creating post request in DRF?

I am making a POST api using DRF. In that api, I need only few fields(name, size, customer_name, customer_address), but don't require this fields(status, ordered_time) because these fields I want to save these fields in run time as status='open' and ordered_time=DateTimeField.now()
views.py
class PizzaOrderCustomerView(APIView):
def post(self, request):
orders = request.data.get('orders')
# Create an article from the above data
serializer = ArticleSerializer(data=orders)
if serializer.is_valid(raise_exception=True):
article_saved = serializer.save()
return Response({"success": "Article '{}' created successfully".format(article_saved.name)})
models.py
class PizzaOrder(models.Model):
name = models.CharField(max_length=120)
size = models.CharField(max_length=10, choices=SIZE_CHOICE, default='MEDIUM')
customer_name = models.CharField(max_length=120)
customer_address = models.TextField()
ordered_time = models.DateTimeField(default=timezone.now, editable=False)
status = models.CharField(max_length=20, default='open', editable=False)
serializers.py
class OrderSerializer(serializers.ModelSerializer):
class Meta:
model = PizzaOrder
# fields = '__all__'
read_only_fields = ('status',)
But when I try to create an order, it needed status and ordered_time also. But it should save at the time of creating order automatically.
Suggest a good way to do it.
from rest_framework import viewsets, mixins
class PizzaViewsets(viewsets.ViewSet, mixins.CreateModelMixin):
model = PizzaOrder
serializer_class = OrderSerializer
queryset = model.objects.all(
serializer, it is always good practise to mention all fields instead of
all
class OrderSerializer(serializers.ModelSerializer):
class Meta:
model = PizzaOrder
fields = ('status','ordered_time','name', 'size', 'customer_name', 'customer_address',)
read_only_fields = ('status','ordered_time',)

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