I need to automatically update my Account
's amount when a Transaction
is created.
I have Transaction
model's model.py
:
class Transaction(models.Model):
user = models.ForeignKey(User, default=None)
account = models.ForeignKey(Account, default=None)
...
Its serializers.py
:
class TransactionSerializer(serializers.ModelSerializer):
class Meta:
model = Transaction
fields = ('id', 'user', 'account_id', 'category_id', 'name', 'amount', 'description', 'created_at')
def create(self, validated_data):
return Transaction.objects.create(**validated_data)
And its views.py
:
class TransactionList(APIView):
def get(self, request):
user_id = request.user.pk
transactions = Transaction.objects.filter(user_id=user_id).order_by('-created_at')
serializer = TransactionSerializer(transactions, many=True)
return Response(serializer.data)
def post(self, request):
account_id = request.data['account_id']
category_id = request.data['category_id']
serializer = TransactionSerializer(data=request.data)
if serializer.is_valid():
serializer.save(user=request.user, account_id=account_id, category_id=category_id)
self.update_account(request)
return Response(serializer.data, status=HTTP_201_CREATED)
return Response(serializer.errors, status=HTTP_400_BAD_REQUEST)
def update_account(self, request):
account_id = request.data['account_id']
category_id = request.data['category_id']
account = Account.objects.get(pk=account_id)
category = Category.objects.get(pk=category_id)
if category.type == 'expense':
account.amount = (account.amount - int(self.request['amount']))
else:
account.amount = (account.amount + int(self.request['amount']))
# Then what?
I thought of creating a custom method that will be executed within the condition if serializer
is valid, that would get the account and category by their id. I could, so far, display the current values they have, such as amount
and name
, but after that, I don't know what to do. I'm imagining I need to use my AccountSerializer
, but I'm not sure.
The easiest way would be to override the save
method of your Transaction
model:
class Transaction(models.Model):
user = models.ForeignKey(User, default=None)
account = models.ForeignKey(Account, default=None)
...
def save(self, force_insert=False, force_update=False, using=None, update_fields=None):
super(Transaction, self).save()
# Update self.account
See Django documentation for details.
The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.