How to set specific faker random string of specific length and using underscores for spaces?

Question

import factory.fuzzy
import faker
from core.strings import underscore_15

from factory import DjangoModelFactory, SubFactory


faker = faker.Factory.create()
class SubProjectFactory(DjangoModelFactory):
    class Meta:
        model = SubProject
        django_get_or_create = ("internal_name",)

    internal_name = factory.Faker('pystr')
    internal_short_name = factory.Faker('pystr')
    underscore_15 = factory.fuzzy.FuzzyText(length=15)
    main_project = SubFactory(MainProjectFactory)

I need the field underscore_15 to be a lower-case string of specifically just 15 characters long and no spaces. If there's any space it should be underscore. I tried to put a function around factory.fuzzy.FuzzyText(length=15). Then I realized that I was assuming FuzzyText returns a string but it was a FuzzyText object.

What should I do?

Answer 1

Well, you can get the FuzzyText objects value by calling like this:

>> f = factory.fuzzy.FuzzyText(length=15)
>> f.fuzz()

But, in this text, the characters can be both uppercase or lower case. So if you want exclusive lower case characters, then you can override the FuzzyText like this:

from factory.fuzzy import FuzzyText

class CustomFuzzyText(FuzzyText):
    def fuzz(self, *args, **kwargs):
       return super(CustomFuzzyText, self).fuzz(*args, **kwargs).lower()

and use it in the factory like this:

underscore_15 = CustomFuzzyText(prefix="aa_", length=12)  # or CustomFuzzyText(length=15)