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Django DRF - nested serializer (level>2) does not show up in the response

We have the follwing structure (library->books->pages)
the first serializer
class Library(serializers.ModelSerializer):
books = BookSerializer(many=True)
class Meta:
model = Library
fields = '__all__'
#transaction.atomic
def create(self, validated_data):
# create logic here
the second serializer
class BookSerializer(serializers.ModelSerializer):
pages = PageSerializer(many=True, required=False)
class Meta:
model = Book
fields = '__all__'
we have an endpoint library/, where we post the payload of the following format
{
"ref": "43a0c953-1380-43dd-a844-bbb97a325586",
"books": [
{
"name": "The Jungle Book",
"author": "Rudyard Kipling",
"pages": [
{
"content": "...",
"pagenumber": 22
}
]
}
]
}
all the objects are created in the database, but the response does not contain pages key. It looks like this
{
"id": 27,
"ref": "43a0c953-1380-43dd-a844-bbb97a325586",
"books": [
{
"id": 34,
"name": "The Jungle Book",
"author": "Rudyard Kipling"
}
]
}
depth attribute does not seem to work. What do I have to do to make pages appear in the responce?

We can achieve the desired behavior using depth in the class Meta of the BookSerializer.
class BookSerializer(serializers.ModelSerializer):
...
class Meta:
...
depth = 3
Copied from documentation
The depth option should be set to an integer value that indicates the depth of relationships that should be traversed before reverting to a flat representation.
Another way to get this behavior would be to use serializer.SerializerMethodField for getting the pages of the book serializer.
class BookSerializer(serializers.ModelSerializer):
pages = serializers.SerializerMethodField()
def get_pages(self, obj):
return PageSerializer(obj.page_set.all(), many=True,).data
...

Trouble sorting JSON results with django rest framework and dynamic rest

I am trying to sort my results by either date or primary key, newer entries in the database first.
models.py
class Notifications(models.Model):
user = models.ForeignKey(User, on_delete=models.CASCADE)
date = models.DateTimeField('date transacted')
read = models.BooleanField(default=False)
message = models.CharField(max_length=300)
views.py
class getnotifications(viewsets.ModelViewSet):
# Database model
queryset = User.objects.all()
# Serializer - this performs the actions on the queried database entry
serializer_class = NotificationsSerializer
# What field in database model will be used to search
lookup_field = 'username'
serializers.py
class NotificationsSerializer(DynamicModelSerializer):
notifications_set = DynamicRelationField('ListNotificationsSerializer', many=True, embed=True)
class Meta:
model = User
fields = ['notifications_set']
class ListNotificationsSerializer(DynamicModelSerializer):
class Meta:
model=Notifications
name='notifications_set'
fields=['pk','date','read','message']
URL accessing request
http://localhost:8000/pm/getnotifications/<omitted>/?sort[]=-notifications_set.pk
JSON results
{
"notifications_set": [
{
"pk": 1,
"date": "2022-10-10T17:11:33.821757Z",
"read": false,
"message": "A user with the phone <omitted> has submitted a restock request for 5 of airpods"
},
{
"pk": 2,
"date": "2022-10-10T00:00:00Z",
"read": false,
"message": "A user with the phone <omitted> has submitted a restock request for 5 of airpods"
},
{
"pk": 3,
"date": "2022-10-10T17:25:11.824385Z",
"read": false,
"message": "A user with the phone <omitted> has submitted a restock request for 5 of airpods"
}
],
"links": {
"notifications_set": "notifications_set/"
}
}
Whether I use -notification_set.pk or notification_set.pk it displays the results in Postman the same way, with no changed order
Using this plugin: https://github.com/AltSchool/dynamic-rest
for sorting
This plugin was linked in the rest framework docs

Django : This field is required on POST request

I'm trying to create a serializer which outputs the Report and also the User information.
My task is accomplished by this serializer:
class ReportSerializer(serializers.ModelSerializer):
latitude = serializers.CharField()
longitude = serializers.CharField()
city = serializers.IntegerField()
type = serializers.IntegerField()
# We have created a field which returns a value from get_marker_icon_url
marker_icon = serializers.SerializerMethodField('get_marker_icon_url')
status_str = serializers.SerializerMethodField('convert_status_toStr')
type_str = serializers.SerializerMethodField('convert_type_toStr')
status_color = serializers.SerializerMethodField('get_status_color')
likes = serializers.SerializerMethodField('random_likes')
user = ReportUserSerializer()
class Meta:
model = Reports
fields = [
'user',
'id',
'type',
'city',
'latitude',
'longitude',
'likes',
'type_str',
'status_str',
'status_color',
'attached_message',
'marker_icon',
'attached_photo',
'date_created'
]
...
With this code my serializer returns a response like this:
[
{
"user": {
"id": 1,
"username": "3nematix",
"profile_pic": "http://192.168.0.29:8000/frontend/static/frontend/images/reports/user_profile_pic.jpg",
"verified": false
},
"id": 1,
"type": 9,
"city": 0,
"latitude": "6.5123333",
"longitude": "51.512586",
"likes": 27,
"type_str": "OTHER",
"status_str": "PENDING",
"status_color": "orange",
"attached_message": "test",
"marker_icon": "OTHER",
"attached_photo": "http://192.168.0.29:8000/frontend/static/frontend/images/reports/user_profile_pic_VRjIYTs.jpg",
"date_created": "2020-10-21T23:19:06.899302Z"
},
......
]
And this is exactly what I need, but the problem is that when I'm trying to create a new object by a POST request, I get this response:
{
"user": [
"This field is required."
]
}
If I would remove 'user' from Meta and user = ReportUserSerializer() from the ReportSerializer class, then I can create a new object, but when I wish to get the Reports I with the Users information I need to add these two again, how can I fix it?

You need to fill the user field yourself before calling save.
Here's the easy way:
class YourView(generics.ListCreateAPIView):
...
def perform_create(self, serializer):
serializer.save(user=self.request.user)
Or slightly differently:
class YourView(generics.ListCreateAPIView):
...
def perform_create(self, serializer):
serializer.validated_data['user'] = self.request.user
return super().perform_create(serializer)

Django REST framework serializer for custom form data

I've started learning how to use the Django REST Framework along with React and I have a quick question. I made a form and use CreateAPIView and UpdateAPIView to create/update items, respectively. But how do I get the contents to populate my <select> field if the list comes from a variable in one of my models?
from model_utils import Choices
class Author(models.Model):
GENDER = Choices('male', 'female', "I don't know really") # How do I get this?
gender = models.CharField(max_length=10, choices=GENDER)
What will the serializer and views for Author.GENDER look like since it's not a model?
At the moment, this is what I have for now.
Django (nothing out of the ordinary here, I think.).
# Serializer.
class AuthorSerializer(serializers.ModelSerializer):
class Meta:
model = Author
fields = ('id', 'gender')
# View
class AuthorUpdateView(UpdateAPIView):
queryset = Author.objects.filter(deleted_at__isnull=True)
serializer_class = AuthorSerializer
React.
componentDidMount() {
const pk = this.props.match.params.pk
axios.get(`http://localhost:8000/api/authors/${pk}`)
.then(response => {
const pk = response.data.id
const gender = response.data.gender
this.setState({gender})
})
.catch(err => console.log(err))
}
I'm open to any direction or concept you might have when using DRF so I can also learn from how you would do it.

Use viewset to combine the logic for a set of your related views (list, create, update)
class AuthorViewSet(ModelViewSet):
queryset = Author.objects.filter(deleted_at__isnull=True)
serializer_class = AuthorSerializer
Make a OPTIONS request to get the metadata for your resource, including the list of valid choices of gender field
Request
OPTIONS /api/authors/
Response
HTTP 200 OK
Allow: GET, POST, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept
{
"name": "Author List",
"parses": [
"application/json",
"application/x-www-form-urlencoded",
"multipart/form-data"
],
"actions": {
"POST": {
"id": {
"type": "integer",
"required": false,
"read_only": true,
"label": "Id"
},
"gender": {
"type": "choice",
"required": true,
"read_only": false,
"label": "Gender",
"choices": [
{
"value": "male",
"display_name": "male"
},
{
"value": "female",
"display_name": "female"
},
{
"value": "I don't know really",
"display_name": "I don't know really"
}
]
}
}
}
}

Get full fields in nested model. Django Rest Framework

I have 2 model classes:
class CustomUser(AbstractUser):
username = models.CharField(max_length=30, unique=True)
tags = models.ManyToManyField('events.Tag', related_name='user_tag', blank=True)
class Tag(models.Model):
name = models.CharField(unique=True, max_length=50)
And serializers:
class UserSerializer(serializers.ModelSerializer):
tags = TagSerializer(many=True)
class Meta:
...
class TagSerializer(serializers.ModelSerializer):
class Meta:
lookup_field = 'name'
model = Tag
fields = ('id', 'name')
When I do a get query I get something like this:
"data": {
"type": "CustomUser",
"id": "6",
"attributes": {
"username": "mercer",
},
"relationships": {
"tags": {
"data": [
{
"type": "Tag",
"id": "1"
}
]
},
}
}
What I want is to get Tag 'name' field in user representation:
"type": "Tag",
"id": "1",
"name":"name"
And I want to make patch query for adding tag to user.
I can use SerializerMethodField(), but this way I will not able to add tags

The problem was with settings of rest framework. I wrote there custom json render classes and recived this form of output. Now i removed it and everything is fine.