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how to Serialize multiple objects in Django

I have 2 models for admin and member positions and I would like to get both of the models in one API call to fetch the data on my front end. How can I achieve this?
class ClinetAdminPosition(models.Model):
name = models.CharField(max_length=128, null=True)
company = models.ForeignKey(
to="Company", on_delete=models.CASCADE, related_name="admin_positions", null=True
)
modified_at = models.DateTimeField(verbose_name="Updated", auto_now=True, editable=True)
created_at = models.DateTimeField(verbose_name="Created", auto_now_add=True, editable=False)
def __str__(self):
return f"{self.name}"
class ClinetMangerPosition(models.Model):
name = models.CharField(max_length=128, null=True)
company = models.ForeignKey(
to="Company", on_delete=models.CASCADE, related_name="manger_positions", null=True
)
modified_at = models.DateTimeField(verbose_name="Updated", auto_now=True, editable=True)
created_at = models.DateTimeField(verbose_name="Created", auto_now_add=True, editable=False)
def __str__(self):
return f"{self.name}"
I want to get both models' data from 1 API request
to be like this:
[
{
"admin_positions": [
{
"name": "test",
"company": 1
},
{
"name": "test2",
"company": 1
},
{
"name": "test3",
"company": 1
}
],
"manger_position": [
{
"name": "test",
"company": 1
},
{
"name": "test2",
"company": 1
},
{
"name": "test3",
"company": 1
}
]
}
]

You can do something like this.
**This is your serializers classes **
class ClinetMangerPositionSerializer(ModelSerializer)
clas Meta:
model = ClinetMangerPosition
fields = ['name','company']
class ClinetAdminPositionSerializer(ModelSerializer):
class Meta:
model = ClinetAdminPosition
fields = ['name','company']
This will be your views class to display data.
from rest_framework.views import APIView
from . import serializers
from rest_framework.response import Response
class ViewName(APIView):
def get(self, request):
admin = ClinetAdminPosition.objects.all()
manager = ClinetMangerPosition.objects.all()
res :{
"admin_positions": serializers.ClinetAdminPositionSerializer(admin, many=True).data
"manager_positions":serializers.ClinetMangerPositionSerializer(manager, many-True).data
}
return Response(res)
something like this,

Let me know if you got any doubt
class ClinetMangerPositionSerializer(ModelSerializer)
clas Meta:
model = ClinetMangerPosition
fields = ['name','company']
class ClinetAdminPositionSerializer(ModelSerializer):
class Meta:
model = ClinetAdminPosition
fields = ['name','company']
class CompanySerializer(MOdelSerializer):
manger_position = ClinetAdminPositionSerializer(many=True,source
='clinetmangerposition')
admin_position = ClinetAdminPositionSerializer(many=True,source
='clinetadminposition')
class Meta:
model= Company
fields = ['manger_position','admin_position']

Correct way to get/create nested objects with DRF?

I have the following models:
class Platform(models.Model): # Get
key = models.CharField(max_length=32, unique=True)
class PlatformVersion(models.Model): # Get or create
platform = models.ForeignKey(Platform, on_delete=models.CASCADE)
major = models.IntegerField(db_index=True)
minor = models.IntegerField(db_index=True)
build = models.IntegerField(db_index=True)
class DeviceManufacturer(models.Model): # Get or create
name = models.CharField(max_length=64, unique=True)
class DeviceModel(models.Model): # Get or create
manufacturer = models.ForeignKey(DeviceManufacturer, on_delete=models.CASCADE)
platform = models.ForeignKey(Platform, on_delete=models.CASCADE)
# ...
# And many others
POST JSON looks like this:
{
"device_model": {
"manufacturer": {
"name": "samsung"
},
"platform": {
"key": "android"
}
},
"version": {
"platform": {
"key": "android"
},
"major": 8,
"minor": 1,
"build": 0
}
}
I have the following serializers:
class PlatformSerializer(serializers.ModelSerializer):
class Meta:
model = Platform
fields = ('name', 'key',)
extra_kwargs = {
'name': {
'read_only': True,
},
}
def create(self, validated_data):
return Platform.objects.get(key=validated_data['key'])
class PlatformVersionSerializer(serializers.ModelSerializer):
platform = PlatformSerializer()
class Meta:
model = PlatformVersion
fields = ('platform', 'major', 'minor', 'build',)
def create(self, validated_data):
# ?
pass
class DeviceManufacturerSerializer(serializers.ModelSerializer):
class Meta:
model = DeviceManufacturer
fields = ('name',)
def create(self, validated_data):
manufacturer, _ = DeviceManufacturer.objects.get_or_create(
defaults={
'name': validated_data['name'],
},
name=validated_data['name']
)
return manufacturer
class DeviceModelSerializer(serializers.ModelSerializer):
manufacturer = DeviceManufacturerSerializer()
platform = PlatformSerializer()
class Meta:
model = DeviceModel
fields = ('manufacturer', 'platform')
def create(self, validated_data):
# ?
pass
I've marked in serializers places where I don't know how to correctly do the object creation, as some of nested objects are «read-only» (I mean that I in fact use get, not create), some of them are get or create.
How should I do it?

Django foreign key rest framework

Is there any way to display the name of the user in the "likedBy" section of the view, instead of the user id? Using django rest framework
From view I get , ignore comments:
[
{
"id": 3,
"title": "ddsa",
"content": "dsadsa",
"created": "2021-02-10T08:07:42.758400Z",
"updated": "2021-02-10T08:07:42.758400Z",
"author": 1,
"category": [
{
"pk": 1,
"name": "Life"
}
],
"likedBy": [
1
],
"comments": [
{
"id": 2,
"content": "ghfa",
"created": "2021-02-10T08:08:02.407950Z",
"post": 3,
"author": 1,
"likedBy": [
1
]
}
]
}
]
Views.py:
class PostViewSet(FlexFieldsMixin, generics.ListAPIView):
queryset = Post.objects.all()
serializer_class = PostSerializer
permit_list_expands = ['category', 'comments']
Models.py
class Post(models.Model):
title = models.CharField(max_length=255)
content = models.TextField()
category = models.ManyToManyField(Category, related_name='posts')
author = models.ForeignKey(User, on_delete=models.CASCADE)
created = models.DateTimeField(auto_now_add=True)
updated = models.DateTimeField(auto_now=True)
likedBy = models.ManyToManyField(User, related_name='posts', blank=True)
class Meta:
ordering = ['-created']
Serializers.py:
class PostSerializer(FlexFieldsModelSerializer):
class Meta:
model = Post
fields = '__all__'
expandable_fields = {
'category': ('blogApi.CategorySerializer', {'many': True}),
'comments': ('blogApi.CommentSerializer', {'many': True}),
}
How serialize ManyToMany field to display text values

Given that you are not serializing a relation, but rather an attribute of your model which is related to your user, I believe you have to use a serializer.SerializerMethodField(). This allows you to do the following:
class PostSerializer(FlexFieldsModelSerializer):
liked_by = serializers.SerializerMethodField(method_name="get_user_likes")
class Meta:
model = Post
fields = (
"title",
"content",
"category",
"author",
"created",
"update",
"liked_by"
)
expandable_fields = {
'category': ('blogApi.CategorySerializer', {'many': True}),
'comments': ('blogApi.CommentSerializer', {'many': True}),
}
#classmethod
def get_user_likes(obj):
# do whatever you like here, but I tend to call a
# method on my model to keep my serializer file
# nice and tidy
# you'll need to define a UserSerializer
return UserSerializer(obj.get_user_likes(), many=True, read_only=True)
And in your Post model:
class Post(models.Model):
title = models.CharField(max_length=255)
content = models.TextField()
category = models.ManyToManyField(Category, related_name='posts')
author = models.ForeignKey(User, on_delete=models.CASCADE)
created = models.DateTimeField(auto_now_add=True)
updated = models.DateTimeField(auto_now=True)
likedBy = models.ManyToManyField(User, related_name='posts', blank=True)
class Meta:
ordering = ['-created']
def get_user_likes(self):
return self.likedBy.all()
You can of course define the full method in your serializer, but as I said I like to keep the serializer as clean as possible and put all methods associated with models in my models.py.
#classmethod
def get_user_likes(obj):
# you'll need to define a UserSerializer
return UserSerializer(obj.likedBy.all(), many=True, read_only=True)

So you can set
likedBy = serializers.ReadOnlyField(source='get_likedBy')
in your PostSerializer class
and define function in your Post model class like below:
#property
def get_likedBy(self):
liked_by = []
for user in self.users_liked_post.all():
liked_by.append(user.name)
return liked_by
just use correct related_name instead of users_liked_post

If you add likedBy to your expandable fields, and then add ?expand=likedBy to your url, it should give you all the information that you outline in the UserSerializer, or write a new serializer named LikedBySerializer. Also as a general rule, try not to use '__all__' it's a good way to leak data. Happy coding!
class LikedBySerializer(FlexFieldsModelSerializer):
class Meta:
model = User
fields = '__all__'
class PostSerializer(FlexFieldsModelSerializer):
class Meta:
model = Post
fields = '__all__'
expandable_fields = {
'category': ('blogApi.CategorySerializer', {'many': True}),
'comments': ('blogApi.CommentSerializer', {'many': True}),
'likedBy': ('blogApi.LikedBySerializer', {'many': True}),
}

Django Serializer's Source argument is not working

I am trying to get all the bills and their customer-related details (i.e. 'customer_code', 'email' etc.) with it.
However, source='user.customer_code does not seem to have any effect at all. What am I missing?
I have been following along this:
this stackoverflow post with no luck.
My two models:
class User(AbstractBaseUser, PermissionsMixin):
email = models.EmailField(db_index=True, unique=True, max_length=200)
customer_code = models.CharField(max_length=300, blank=True, null=True, default=None)
class Bill(models.Model):
customer = models.ForeignKey(
User, on_delete=models.CASCADE, blank=True, null=True, related_name="customer_bill"
)
payable_amount = models.DecimalField(max_digits=10, decimal_places=2, default=0)
View:
class BillView(APIView):
def get(self, request, format=None):
q = Bill.objects.all().select_related('customer')
s = BillSerializer(q, many=True)
return JsonResponse({
"bill": s.data
})
Serializer:
class BillSerializer(serializers.ModelSerializer):
customer_code = serializers.CharField(source='user.customer_code', read_only=True)
class Meta:
model = Bill
fields = ('id','payable_amount','customer_code') # binding customer_code here
Current Output:
"bill": [
{
"id": 1,
"payable_amount": "1000.00"
},
{
"id": 2,
"payable_amount": "2000.00"
}
]
Expected Result:
"bill": [
{
"id": 1,
"payable_amount": "1000.00",
"customer_code": "CUS10001" # want this to be attached
},
{
"id": 2,
"payable_amount": "2000.00",
"customer_code": "CUS10002" # want this to be attached
}
]

Django Rest Framework foreign key nesting

I am trying to nest my Users table inside my Relationships table. So instead of this:
[
{
"user": 1,
"related_user": 2,
"relationship": "followed_by"
}
]
I am trying to get this:
[
{
"user": {
"username": "user1",
"name": "User 1",
"email": "bla",
"phone": "bla",
"date_joined": "2017-11-01T21:34:13.101256Z"
},
"related_user": {
"username": "user2",
"name": "User 2",
"email": "bla",
"phone": "bla",
"date_joined": "2017-11-01T21:34:13.101256Z"
},
"relationship": "followed_by"
}
]
I looked up tutorials and I tried adding serializers.RelatedField , UserSerializer(many=true, read-only=true) etc. but nothing worked
Models.py
class User(models.Model):
username = models.CharField(max_length=255)
name = models.CharField(max_length=255)
email = models.CharField(max_length=255)
phone = models.CharField(max_length=255)
date_joined = models.DateTimeField(auto_now_add=True, blank=True)
def __str__(self):
return str(self.pk) + ", " + self.username
RELATIONSHIP_CHOICE = [
("follows", "follows"),
("followed_by", "followed_by"),
("none", "none"),
]
class Relationship(models.Model):
user = models.ForeignKey(User, related_name="primary_user", null=True)
related_user = models.ForeignKey(User, related_name="related_user", null=True)
relationship = models.CharField(max_length=40, choices=RELATIONSHIP_CHOICE, default=RELATIONSHIP_CHOICE[0])
Serializers.py
from rest_framework import serializers
from . import models
class UserSerializer(serializers.ModelSerializer):
class Meta:
model = models.User
fields = (
'username',
'name',
'email',
'phone',
'date_joined',
)
class RelationshipSerializer(serializers.ModelSerializer):
related_user = UserSerializer(many=True)
class Meta:
model = models.Relationship
fields = (
'user',
'related_user',
'relationship',
'related_user'
)
I tried to add related user to my serializer but it didnt work. I am getting an error: 'User' object is not iterable
Any help is appreciated.

class RelationshipSerializer(serializers.ModelSerializer):
user = UserSerializer(read_only=True)
related_user = UserSerializer(read_only=True)
class Meta:
model = models.Relationship
fields = (
'user',
'related_user',
'relationship'
)
user = UserSerializer(read_only=True, many=True) is for manytomany field,user = UserSerializer(read_only=True) is for ForeignKey field.