Add group to user in Django - django

Question

I have created 3 groups 1. Staff, 2. Admin, 3. Operational Manager and assigned permission. Now whenever I wanted to add new user I wanted to show the choice field of the group and able to select the group.
As per the framework the User and Groups have many-to-many relations and I am trying to implement nested serializer. And as per documentation to add nested data I need to implement create or update method in the serializer but here I am not getting the choice field in group and the data is null.
GroupSerializer:
class GroupSerializer(serializers.ModelSerializer):
class Meta:
model = Group
fields = ('name',)
UserSerializers:
class UserSerializers(serializers.ModelSerializer):
groups = GroupSerializer(many=True)
class Meta:
model = User
fields = ('first_name', 'last_name','address','contact', 'email', 'date_of_birth', 'branch', 'groups')
def create(self, validated_data):
groups_data = validated_data.pop('groups')
user = User.objects.create(**validated_data)
for group_data in groups_data:
Group.objects.create(user=user, **group_data)
return user
when I wanted to make a post request I am getting :
{
"first_name": "",
"last_name": "",
"address": "",
"contact": null,
"email": "",
"date_of_birth": null,
"branch": null,
"groups": []
}
here groups fields are empty.
If I try to make a post request it says
{
"groups": [
"This field is required."
]
}
Edit : Solved
I removed GroupSerializer because User model has many-to-many relation with Group so we don't need to explicitly specify Group object
# class GroupSerializer(serializers.ModelSerializer):
# class Meta:
# model = Group
# fields = ('name',)
class UserSerializers(serializers.ModelSerializer):
# groups = GroupSerializer(many=True)
class Meta:
model = User
fields = ('username','first_name', 'last_name','address','contact', 'email', 'date_of_birth', 'branch', 'groups')
def create(self, validated_data):
groups_data = validated_data.pop('groups')
user = User.objects.create(**validated_data)
for group_data in groups_data:
# Group.objects.create(user=user, **group_data)
user.groups.add(group_data)
return user

Answer 1

You can use PrimarykeyRelatedField and provide id of groups that you want to add in a list. like below:
class UserSerializers(serializers.ModelSerializer):
groups = serializers.PrimaryKeyRelatedField(queryset=Group.objects.all())
class Meta:
model = User
fields = ('first_name', 'last_name', 'address', 'contact', 'email', 'date_of_birth', 'branch', 'groups')
def create(self, validated_data):
groups_data = validated_data.pop('groups')
user = User.objects.create(**validated_data)
for group_data in groups_data:
Group.objects.create(user=user, **group_data)
return user
def to_representation(self, instance):
r = super(UserSerializers, self).to_representation(instance)
r.update({
'groups': GroupSerializer(many=True).to_representation(instance.groups)
})
return r
So just provide list of groups like this: "groups": [1,2,3]
and you should also override to_representation method if you want to have serialized json result of each group in response.