Django Rest Framework foreign key nesting - python

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.

Related

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']

How to set nested related fields serializers in Djando Rest Framework?

I'm using Django Rest Framework to build an API where I have the following models of Users making, confirming and showing interest on Events:
models.py
class User(AbstractBaseUser, PermissionsMixin):
user_name = models.CharField(_("user name"), max_length=150, unique=True)
slug = AutoSlugField(populate_from='user_name', unique=True)
class Event(models.Model):
name = models.CharField(max_length=100, blank=False, null=False)
owner = models.ForeignKey(User, related_name="owned_events", on_delete=models.SET_NULL, blank=True, null=True)
confirmed = models.ManyToManyField(User, related_name="confirmed_events", blank=True)
interested = models.ManyToManyField(User, related_name="interested_events", blank=True)
to serialize it I used the following code as I found here and at the DRF docs:
serializers.py
class UserSerializer(serializers.HyperlinkedModelSerializer):
class Meta:
model = User
fields = [
"url",
"user_name",
"password",
]
extra_kwargs = { "password": {"write_only": True} }
class EventSerializer(serializers.HyperlinkedModelSerializer):
owner = UserSerializer(required=False)
confirmed = UserSerializer(required=False, many=True)
interested = UserSerializer(required=False, many=True)
class Meta:
model = Event
lookup_field = 'slug'
extra_kwargs = { 'url': {'lookup_field': 'slug'} }
fields = [
"url",
"owner",
"name",
"confirmed",
"interested",
]
It works just fine like that, but I wanted the UserSerializer to show confirmed and interested events of each user just like each event shows the users confirmed and interested. I changed serializers and got the url of each event, like that:
serializers.py with HyperlinkedRelatedField on UserSerializer
class UserSerializer(serializers.HyperlinkedModelSerializer):
confirmed_events = serializers.HyperlinkedRelatedField(
queryset=Event.objects.all(),
view_name='event-detail',
lookup_field='slug',
many=True,
required=False
)
interested_events = serializers.HyperlinkedRelatedField(
queryset=Event.objects.all(),
view_name='event-detail',
lookup_field='slug',
many=True,
required=False
)
class Meta:
model = User
fields = [
"url",
"user_name",
"password",
"confirmed_events",
"interested_events",
]
extra_kwargs = { "password": {"write_only": True} }
This got me the following JSON from the User model:
{
"user_name": "d",
"confirmed_events": [],
"interested_events": [
"http://localhost:8000/events/eqwer-2/",
"http://localhost:8000/events/test/",
"http://localhost:8000/events/test-2/",
"http://localhost:8000/events/test-3/",
]
}
And from the Event model:
{
"url": "http://localhost:8000/events/eqwer-2/",
"owner": null,
"name": "eqwer",
"slug": "eqwer-2",
"confirmed": [],
"interested": [
{
"user_name": "d",
"confirmed_events": [],
"interested_events": [
"http://localhost:8000/events/eqwer-2/",
"http://localhost:8000/events/test/",
"http://localhost:8000/events/test-2/",
"http://localhost:8000/events/test-3/",
]
}
]
},
The Event model JSON is fine because it shows each user's data, but I wanted the User JSON to show each event data instead of just the event URL, it'd be something like:
{
"user_name": "d",
"confirmed_events": [],
"interested_events": [
{
"url": "http://localhost:8000/events/eqwer-2/",
"owner": null,
"name": "eqwer",
"slug": "eqwer-2",
},
]
}
Create a separate serializer for interested_events like so:
class InterestedEventsSerializer(serializers.HyperlinkedModelSerializer):
class Meta:
fields = ('url', 'owner', 'name', 'slug')
And in your UserSerializer declare the interested_events using the serializer above:
class UserSerializer(serializers.HyperlinkedModelSerializer):
confirmed_events = ... #
interested_events = InterestedEventsSerializer(many=True)
class Meta:
model = User
fields = [
"url",
"user_name",
"password",
"confirmed_events",
"interested_events",
]
extra_kwargs = { "password": {"write_only": True} }

Unable to populate images in Django Rest Serializer

I'm developing a REST API using Django Rest Framework but I'm unable to populate image in Feed Serializer
Django Version: 3.1.7
Python Version: 3.9.2
Models:
class User(AbstractUser):
age = models.PositiveIntegerField(null=True)
address = models.TextField(null=True)
email = models.EmailField(_('email address'), unique=True, null=False)
first_name = models.CharField(_('first name'), max_length=150, blank=False, null=False)
last_name = models.CharField(_('last name'), max_length=150, blank=False, null=False)
image = models.ImageField(upload_to='storage', null=True)
class Feed(models.Model):
description = models.TextField()
likes_count = models.PositiveIntegerField(default=0, null=True)
comments_count = models.PositiveIntegerField(default=0, null=True)
updated_at = models.DateTimeField(auto_now=True)
created_at = models.DateTimeField(auto_now_add=True)
user = models.ForeignKey(User, on_delete=models.CASCADE, related_name='user')
tags = models.ManyToManyField(User, related_name='tags', blank=True)
class FeedImage(models.Model):
path = models.ImageField(upload_to='storage', null=False)
post = models.ForeignKey(Feed, on_delete=models.CASCADE, null=False, default='')
Serializers:
class FeedUserSerializer(ModelSerializer):
class Meta:
model = User
fields = ('id', 'first_name', 'last_name', 'image')
class FeedImageSerializer(serializers.ModelSerializer):
class Meta:
model = FeedImage
fields = ('id', 'path', 'post')
class FeedSerializer(ModelSerializer):
user = FeedUserSerializer()
images = FeedImageSerializer(many=True, read_only=True)
class Meta:
model = Feed
fields = ('id', 'description', 'comments_count', 'likes_count', 'updated_at', 'created_at',
'tags', 'images', 'user')
View:
class FeedsListView(generics.ListAPIView):
queryset = Feed.objects.all()
return FeedSerializer
Problem: I get this result without images
[{
"id": 1,
"description": "Hello world",
"comments_count": 0,
"likes_count": 0,
"updated_at": "2021-04-26T03:01:44.219235Z",
"created_at": "2021-04-26T03:01:44.219235Z",
"tags": [],
"user": {
"id": 1,
"first_name": "ZAIN",
"last_name": "REHMAN",
"image": "http://192.168.88.28:8000/storage/1_Facebook_1.jpg"
}
}]
Expected Output:
[{
"id": 1,
"description": "Hello world",
"comments_count": 0,
"likes_count": 0,
"updated_at": "2021-04-26T03:01:44.219235Z",
"created_at": "2021-04-26T03:01:44.219235Z",
"tags": [],
"user": {
"id": 1,
"first_name": "abc_first",
"last_name": "cdef_last",
"image": "http://192.168.88.28:8000/storage/1_Facebook_1.jpg"
},
"images": [
{
"id": 1,
"post": "1",
"path": "imagelocation"
},
{
"id": 2,
"post": "1",
"path": "imagelocation 2"
}
]
}]
Any solution or any workaround will be appreciated.
Ignore this: Bulk text to resolve StackOverflow problem
industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book.
You can use SerializerMethodField for this.
class FeedSerializer(ModelSerializer):
images = serializers.SerializerMethodField()
class Meta:
model = Feed
fields = ('id', 'description', 'comments_count', 'likes_count', 'updated_at', 'created_at',
'tags', 'images', 'user')
def get_images(self, obj):
return obj.feedimage_set.all().values('id', 'path', 'post')

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
}
]

Correcting Django User Model Foreign Key issue

I am using the built-in django user model. I keep getting the error django.db.utils.IntegrityError: FOREIGN KEY constraint failed
I did not use the user model in any other models and vice-versa.
models.py looks like this
from django.contrib.auth.models import User
from django.utils import timezone
from django.db.models import CharField
from django.db.models import BooleanField
from django.db.models import TextField
from django.db.models import DateTimeField
class Course(models.Model):
id = models.AutoField(primary_key=True)
name = CharField(max_length=100)
class Project(models.Model):
id = models.AutoField(primary_key=True)
desc = CharField(max_length=150)
name = CharField(max_length=50)
storyboard_file_path = TextField()
storyboard_completed = BooleanField(default=False)
filming_complete = BooleanField(default=False)
audio_complete = BooleanField(default=False)
production_complete = BooleanField(default=False)
aggregation_complete = BooleanField(default=False)
video_file_path = TextField()
final_review_complete = BooleanField(default=False)
course = models.ForeignKey(Course, on_delete=models.CASCADE, related_name="projects", null=True, blank=True)
class Status(models.Model):
status_id = models.IntegerField(primary_key=True)
desc = CharField(max_length=150)
name = CharField(max_length=50)
class Event(models.Model):
project_id = models.ForeignKey(Project, on_delete=models.CASCADE, null=True, blank=True)
status_id = models.ForeignKey(Status, on_delete=models.CASCADE, null=True, blank=True)
datetime = models.DateTimeField(auto_now_add=True, blank=True)
serializers.py looks like this
from rest_framework import serializers
from .models import Event
from .models import Project
from .models import Course
from rest_framework_jwt.settings import api_settings
class UserSerializer(serializers.ModelSerializer):
class Meta:
model = User
fields = ('id',
"password",
"last_login",
"is_superuser",
"username",
"first_name",
"last_name",
"email",
"is_staff",
"is_active",
"date_joined",
"groups",
"user_permissions")
def create(self, validated_data):
password = validated_data.pop('password', None)
instance = self.Meta.model(**validated_data)
if password is not None:
instance.set_password(password)
instance.save()
return instance
def update(self, instance, validated_data):
for attr, value in validated_data.items():
if attr == 'password':
instance.set_password(value)
else:
setattr(instance, attr, value)
instance.save()
return instance
def get_jwt_token(user):
jwt_payload_handler = api_settings.JWT_PAYLOAD_HANDLER
jwt_encode_handler = api_settings.JWT_ENCODE_HANDLER
payload = jwt_payload_handler(user)
return jwt_encode_handler(payload)
class ProjectSerializer(serializers.ModelSerializer):
class Meta:
model = Project
fields = ('id', 'desc', 'name', 'storyboard_file_path',
'storyboard_completed', 'filming_complete', 'audio_complete',
'production_complete', 'aggregation_complete', 'video_file_path',
'final_review_complete', 'course')
def create(self, validated_data):
instance = self.Meta.model(**validated_data)
instance.save()
return instance
def update(self, instance, validated_data):
for attr, value in validated_data.items():
setattr(instance, attr, value)
instance.save()
return instance
class CouserSerializer(serializers.ModelSerializer):
projects = ProjectSerializer(many=True, read_only=True)
class Meta:
model = Course
fields = ('id', 'name', 'projects')
def create(self, validated_data):
instance = self.Meta.model(**validated_data)
instance.save()
return instance
I am trying to load in the fixture
{
"model": "auth.user",
"pk": 1,
"fields": {
"password": "pbkdf2_sha256$120000$V2isoXl1Q88l$sVuB+25I6UNNLY76Ti0EixAu/Ucimqi7rFpbadDzqzc=",
"last_login": null,
"is_superuser": true,
"username": "admin#admin.com",
"first_name": "Admin",
"last_name": "User",
"email": "admin#admin.com",
"is_staff": true,
"is_active": true,
"date_joined": "2019-04-16T00:16:13.252Z",
"groups": [1],
"user_permissions": []
}
},
{
"model": "auth.user",
"pk": 2,
"fields": {
"password": "pbkdf2_sha256$120000$6YHv5JMayFnN$+Y2TqedyjZq02kEw/0ZaXtyigzaH2+BRUIqqkSeAG90=",
"last_login": null,
"is_superuser": false,
"username": "content#content.com",
"first_name": "Content",
"last_name": "Manager",
"email": "content#content.com",
"is_staff": true,
"is_active": true,
"date_joined": "2019-04-16T00:19:01.130Z",
"groups": [2],
"user_permissions": []
}
}
]
I do not understand where this foreign key error is coming from. Any help would be appreciated.
It is probably the groups. Do those groups exist (before the users). If not you would get this error.

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