How create trigger in Django Rest Framework to change booleanfield? - django

Question

I have a question in django rest framework. Since I'm learning how to use some advanced options, I do not quite understand. I need to currently change a booleanfield every time a foreignkey is inserted into table.
How can I do this in model ?
Model:
class Persona(models.Model):
name = models.CharField(max_length=32)
cart = models.ForeignKey(Credit,null=True)
rg = models.IntergerField()
end = models.CharField(max_length=256)
details = models.TextField(blank=True, null=True)
order = models.ForeignKey(Order, null=True)
def __str__(self):
return self.cart
class Meta:
db_table='person'
app_label = 'bank'
class Credit(models.Model):
number = models.CharField(max_length=16, unique=True)
create_at = models.DateField(auto_add_now=True)
updated_at = models.DateField()
available = models.BooleanField()
def __str__(self):
return self.number
class Meta:
db_table = 'credit'
app_label = 'bank'
Serializer:
class PersonaSerializer(serializers.ModelSerializer):
order__id = serializers.ReadOnlyField(source='order.id')
class Meta:
model = Persona
fields = '__all__'
class Persona(viewsets.ModelViewSet):
allowed_methods = ('GET', 'POST', 'PUT', 'PATCH')
queryset = Persona.objects.all()
serializer_class = PersonaSerializer

Answer 1

You can override the create method on the ModelSerializer to achieve this:
def create(self, validated_data):
cart = validated_data['cart']
persona = super(PersonaSerializer, self).create(validated_data)
cart.available = True # update boolean
cart.save()
return persona
You can read more about this in the docs
If you want to handle this in your model you can override the Persona model save method:
class Persona(models.Model):
name = models.CharField(max_length=32)
cart = models.ForeignKey(Credit,null=True)
rg = models.IntergerField()
end = models.CharField(max_length=256)
details = models.TextField(blank=True, null=True)
order = models.ForeignKey(Order, null=True)
def __str__(self):
return self.cart
class Meta:
db_table='person'
app_label = 'bank'
def save(self, *args, **kwargs):
# Will only update the available field when the Persona
# instance is created and the cart field is not null
if not self.pk and self.cart:
self.cart.available = True
self.cart.save()
return super(Persona, self).save(*args, **kwargs)