TypeError: __str__ returned non-string (type NoneType)

[sentry-io]

Sentry Issue: DJANGO-GIRLS-WEBSITE-6G

TypeError: __str__ returned non-string (type NoneType)
(7 additional frame(s) were not displayed)
...
  File "django/utils/decorators.py", line 43, in _wrapper
    return bound_method(*args, **kwargs)
  File "django/utils/decorators.py", line 130, in _wrapped_view
    response = view_func(request, *args, **kwargs)
  File "django/contrib/admin/options.py", line 1540, in changeform_view
    return self._changeform_view(request, object_id, form_url, extra_context)
  File "django/contrib/admin/options.py", line 1590, in _changeform_view
    self.log_addition(request, new_object, change_message)
  File "django/contrib/admin/options.py", line 815, in log_addition
    object_repr=str(object),

[vanessa]

This stack trace isn't giving us much to go on. It would be helpful to know which page caused this error, and what object it was attempting to access, among other details.

@marksweb do you have any context on this that could help us find the culprit? Thank you!

[marksweb]

@vanessa this is what I can get at the moment.

We could do with Anna getting some time to invite you to sentry

[vanessa]

Thank you. That is helpful! I contacted Anna to ask that.

[kewtree1408]

Hey! I'm one of the organisers DjangoGirls in Amsterdam.
I noticed that I can't add Sponsors and Coaches to admin panel.

Could it be related to this issue?

[marksweb]

@kewtree1408 yes, it looks like the string method for a sponsor is problematic. It tries to return a sponsor name, but it's an optional field so could well be that NoneType that sentry is talking about.

I also see that an application tries to return it's primary key but you could have an instance of an application which hasn't been saved to the database yet and therefore would not have a primary key.