Display data that no model exists in a serializer - Python - Django - Django Rest Framework

Question

I have a "Model-Viewset-Serializer" and I need my Serializer to display additional fields that don't exist in the model.

Model:

class MyModel(models.Model):
    id = models.UUIDField(primary_key=True, unique=True, default=uuid.uuid4, editable=False, null=False)
    type = models.CharField(max_length=100, null=False, blank=False)
    name = models.CharField(max_length=100, null=False, blank=False)

Viewset:

class MyViewSet(
    mixins.ListModelMixin,
    mixins.CreateModelMixin,
    mixins.UpdateModelMixin,
    mixins.DestroyModelMixin,
    mixins.RetrieveModelMixin,
    viewsets.GenericViewSet
):
    permission_classes = [permissions.AllowAny]
    queryset = MyModel.objects.all()
    serializer_class = MySerializer

    def list(self, request, *args, **kwargs):
        queryset = MyModel.objects.filter(organization_id=request.user.my_connection_id)
        page = self.paginate_queryset(queryset)
        serializer = MySerializer(page, many=True)
        return self.get_paginated_response(serializer.data)

Serializer:

class MySerializer(ModelSerializer):
    class Meta:
        model = MyModel
        fields = ('id', 'type', 'name', 'description', 'array')

I need to add the following object to the preview

array:

[
    {'status': 'ok', 'value': '1'},
    {'status': 'pending', 'value': '5'},
    {'status': 'approval', 'value': '3'},
    {'status': 'rejected', 'value': '4'}
]

description: 'text description'

On which endpoint do you want this additional fields, and how do you build it? — Brian Destura, Jun 30 '21 at 04:17

score 0 · Answer 1 · edited Jun 30 '21 at 04:28

You can create raw properties in your Serializer suppose that you have that data array in some part of you code where data is the value you want to add to your Serializer:

data = [
    {'status': 'ok', 'value': '1'},
    {'status': 'pending', 'value': '5'},
    {'status': 'approval', 'value': '3'},
    {'status': 'rejected', 'value': '4'}
]

Then you can add the following property to your serializer MySerializer and it will look like this:

class MySerializer(ModelSerializer):
    array = serializers.ReadOnlyField(default=data)
    class Meta:
        model = MyModel
        fields = ('id', 'type', 'name', 'description', 'array')

Where array is custom property of your serializer, ReadOnlyField is used in different ways like displaying related info instead of the pk in a relationship.

score 0 · Answer 2 · answered Jun 30 '21 at 05:03

0

You can create additional fields in your serializer with using SerializerMethodField.

https://www.django-rest-framework.org/api-guide/fields/#serializermethodfield

answered Jun 30 '21 at 05:03

arif

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Display data that no model exists in a serializer - Python - Django - Django Rest Framework

2 Answers2