Wsrtjtyk

In my models.py, I have:

def MakeOTP():

    import random,string

    return ''.join(random.choices(string.digits, k=4))





class Prescriptionshare(models.Model):

    prid = models.AutoField(primary_key=True, unique=True)

    customer = models.ForeignKey(

        customer, on_delete=models.CASCADE, null=True)

    time = models.DateTimeField(default=timezone.now)

    checkin =models.ForeignKey(Checkins, on_delete=models.CASCADE, null=True)

    otp = models.CharField(max_length=5, default=MakeOTP())

In my django shell, I've tried the following:

pq = Prescriptionshare(customer = cus, checkin = chk)

pq.save()

The problem is that each time this is executed, I get the same string in otp field. There is no random change of string.
Why is this happening?

remove the () from default=MakeOTP()

class Prescriptionshare(models.Model):

    # your code

    otp = models.CharField(max_length=5, default=MakeOTP) # here, remove the "()"

After making changes in the models, you should migrate the DB

Why this happening?

If you use MakeOTP(), Django takes the output of the function, where as if you use MakeOTP (without parenthesis) Django consider it as callable function.


That is, when paranthesis used, method is called once the migrations are run and its value is used as the default value and when paranthesis are not used, function reference called everytime while object creation.