How do I POST multiple JSON objects

Question

I would like to know how to go about posting multiple JSON objects to the server using django-restframework. My datatable model is given below.

class module(models.Model):
uploaded_by=models.ForeignKey(ChangeLog,on_delete=models.CASCADE,null=True)
panel_manufacturer= models.CharField(max_length=100,null=True, blank = True)
panel_model= models.CharField(max_length=100,null=True, blank = True)
panel_serial_number = models.CharField(max_length=100)
label_pmpp=models.FloatField(null=True, blank = True)
label_lower_tolerance=models.FloatField(null=True, blank = True)
label_upper_tolerance=models.FloatField(null=True, blank = True)
label_isc=models.FloatField(null=True, blank = True)
label_voc=models.FloatField(null=True, blank = True)
label_maximum_system_voltage=models.FloatField(null=True, blank = True)
additional_panel_information = JSONField(null=True, blank = True)
def __str__(self):
    return self.panel_serial_number

And the corresponding serializer is as such

class module_Serializer(serializers.HyperlinkedModelSerializer):
url = serializers.HyperlinkedIdentityField(view_name="pvlabs_testdata:module-detail")
uploaded_by = ChangeLog_Serializer(required=False)
class Meta:
    model = module
    fields = '__all__'
    validators = [module_validator]

def create(self, validated_data):
    uploaded_by_data = {"uploaded_by":self.context['request'].user, "upload_timestamp":datetime.now()}
    uploaded_by_instance = ChangeLog.objects.create(**uploaded_by_data)
    module_instance=module.objects.create(uploaded_by=uploaded_by_instance, **validated_data)
    return module_instance

When I go about posting a JSON like below

{
"panel_manufacturer": "XYZ",
"panel_model": null,
"panel_serial_number": "EFG",
"label_pmpp": null,
"label_lower_tolerance": null,
"label_upper_tolerance": null,
"label_isc": null,
"label_voc": null,
"label_maximum_system_voltage": null,
"additional_panel_information": null
 },
 {
"panel_manufacturer": "XYZ",
"panel_model": null,
"panel_serial_number": "ABC",
"label_pmpp": null,
"label_lower_tolerance": null,
"label_upper_tolerance": null,
"label_isc": null,
"label_voc": null,
"label_maximum_system_voltage": null,
"additional_panel_information": null
},
 {
"panel_manufacturer": "XYZ",
"panel_model": null,
"panel_serial_number": "ABC",
"label_pmpp": null,
"label_lower_tolerance": null,
"label_upper_tolerance": null,
"label_isc": null,
"label_voc": null,
"label_maximum_system_voltage": null,
"additional_panel_information": null
}

I always get an error that says 'Expected dict, got list'.

Answer 1

I managed to create a solution for this using list serializer. So in my views file, it is coded as below

class module_ViewSet(viewsets.ModelViewSet):
"""
API endpoint that allows groups to be viewed or edited.
"""
queryset = module.objects.all()
serializer_class = module_Serializer
permission_classes = [permissions.IsAuthenticated | HasAPIKey]
def get_serializer(self, *args, **kwargs):
    if isinstance(kwargs.get("data", {}), list):
        kwargs["many"] = True
        temp= kwargs.get("data")
        for i in range(len(kwargs.get("data"))):
            for key, value in temp[i].items():
                if " " in key or key.islower()==0:
                    n_key=str(key).replace(" ", "_").title().lower()
                    kwargs.get("data")[i][n_key] = kwargs.get("data")[i].pop(key)

    return super(module_ViewSet, self).get_serializer(*args, **kwargs)

And for my serializer I have coded as below

from rest_framework import serializers
from django_restql.mixins import DynamicFieldsMixin
class BulkModuleSerializer(DynamicFieldsMixin, serializers.ListSerializer):
    def create(self, validated_data):
        result=[]
        for validated_datas in validated_data:
            uploaded_by_data = {"uploaded_by":self.context['request'].user, "upload_timestamp":datetime.now()}
            uploaded_by_instance = ChangeLog.objects.create(**uploaded_by_data)
            module_instance=module.objects.create(uploaded_by=uploaded_by_instance, **validated_datas)
            result.append(module_instance)
        return result
class module_Serializer(DynamicFieldsMixin, serializers.HyperlinkedModelSerializer):
    url = serializers.HyperlinkedIdentityField(view_name="pvlabs_testdata:module-detail")
    uploaded_by = ChangeLog_Serializer(required=False)

    class Meta:
        model = module
        fields = '__all__'
        validators = [module_validator]
        list_serializer_class = BulkModuleSerializer

    def create(self, validated_data):
        uploaded_by_data = {"uploaded_by":self.context['request'].user, "upload_timestamp":datetime.now()}
        uploaded_by_instance = ChangeLog.objects.create(**uploaded_by_data)
        module_instance=module.objects.create(uploaded_by=uploaded_by_instance, **validated_data)
        return module_instance

That seems to have worked for me.

Answer 2

You have put your JSON data inside square brackets. Example:

[
    {
        "panel_manufacturer": "XYZ",
        "panel_model": null,
        "panel_serial_number": "ABC",
        "label_pmpp": null,
        "label_lower_tolerance": null,
        "label_upper_tolerance": null,
        "label_isc": null,
        "label_voc": null,
        "label_maximum_system_voltage": null,
        "additional_panel_information": null
    },
    {
        "panel_manufacturer": "XYZ",
        "panel_model": null,
        "panel_serial_number": "ABC",
        "label_pmpp": null,
        "label_lower_tolerance": null,
        "label_upper_tolerance": null,
        "label_isc": null,
        "label_voc": null,
        "label_maximum_system_voltage": null,
        "additional_panel_information": null
    }
]