ValueError: invalid literal for int() with base 10:

[Alexander Joseph]

Hello, I came across this error:

"ValueError: invalid literal for int() with base 10:" after I made a field in my models.py a ForeignKey. Below is my models.py

from django.conf import settings

from django.db import models

from django.core.urlresolvers import reverse

from django.utils import timezone

import datetime

from contacts.models import Contact

#from django.contrib.auth.models import User

# Create your models here.

class Invoice(models.Model):

    created_at = models.DateTimeField(auto_now_add=True)

    their_company = models.ForeignKey(Contact, on_delete=models.CASCADE,blank=True,

    null=True,)

    invoice_number = models.CharField(max_length=50, default='')

    bill_to = models.CharField(max_length=255, default='')

    created_by = models.ForeignKey(settings.AUTH_USER_MODEL)

    

    def save(self, *args, **kwargs):

        if not self.id:

            today = datetime.date.today()

            date_str = datetime.datetime.strftime(today, '%y%m%d')

            doc_str = 'ACIN'

            last_invoice = Invoice.objects.filter(invoice_number__startswith=doc_str).order_by('invoice_number').last()

            if last_invoice:

                last_invoice_num = last_invoice.invoice_number[-2:]

                new_invoice_num = int(last_invoice_num) + 1

                new_invoice_num = "%02d" % new_invoice_num

            else:

                new_invoice_num = '01'

            self.invoice_number = doc_str + date_str + new_invoice_num

        super(Invoice, self).save(*args, **kwargs)

        

        

    class Meta:

        ordering = ['invoice_number', ]

        

    def __str__(self):

        return self.invoice_number

        

    def get_absolute_url(self):

        return reverse("accounting:invoices:detail", kwargs={"pk": self.pk})

The 'their_company' field I think is whats giving the error. I think it is because it is trying to convert that field to an int but its not something that can be converted to an int. I'm new to django and I know I have something configured wrong somewhere but not sure where. 

Thanks for your help

[Tim Chase]

On 2017-07-26 11:52, Alexander Joseph wrote:
> "*ValueError: invalid literal for int() with base 10:*" after I

> made a field in my models.py a ForeignKey. Below is my models.py

The problem lies in this line:

> new_invoice_num = int(last_invoice_num) + 1

For some reason last_invoice_num is an invalid value to pass to
int(). You'd have to check what that actual value is that you're
passing to the function. The error message *should* specify what
that value is:

>>> int("x")
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ValueError: invalid literal for int() with base 10: 'x'
>>> int("")
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ValueError: invalid literal for int() with base 10: ''

but you seem to have truncated it so it's a little hard to tell from
the error message. It's not None as that produces a different
message:

>>> int(None)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: int() argument must be a string, a bytes-like object or a
number, not 'NoneType'

-tkc

[Alexander Joseph]

Hi, thanks for the reply, however when I take out the 'their_company' field altogether everything works fine. Also in the error it references the their_company field. The entire error is  "invalid literal for int() with base 10: 'NewCor'" NewCor is a company in the contacts table. Thanks

[Alexander Joseph]

The problem was I had records in the database from before I changed the 'their_company' field to a ForeignKey. Before it was a CharField so some of the records had actual company names in them. I deleted those records since there wasnt any real data in there anyways, just dummy data. Everything works the way its supposed to now.