prevent migration errors on django 1.8 by declaring the SafeDeleteManager (internal class in managers) as global

[barseghyanartur]

myapp/models.py

    from django.utils import six, timezone
    from django.db import models
    from django.contrib.auth.models import (
        AbstractBaseUser, PermissionsMixin, BaseUserManager
    )
    from django.core.mail import send_mail
    from django.utils.translation import ugettext_lazy as _

    from safedelete.models import safedelete_mixin_factory
    from safedelete.utils import SOFT_DELETE

    class UserManager(BaseUserManager):
        """
        User manager.
        """
        use_in_migrations = True

        def _create_user(self, email, password,
                         is_staff, is_superuser, **extra_fields):
            """
            Creates and saves a User with the given username, email and password.
            """
            now = timezone.now()
            if not email:
                raise ValueError('The given email must be set')
            email = self.normalize_email(email)
            user = self.model(email=email,
                              is_staff=is_staff, is_active=True,
                              is_superuser=is_superuser,
                              date_joined=now, **extra_fields)
            user.set_password(password)
            user.save(using=self._db)
            return user

        def create_user(self, email=None, password=None, **extra_fields):
            return self._create_user(email, password, False, False,
                                     **extra_fields)

        def create_superuser(self, email, password, **extra_fields):
            return self._create_user(email, password, True, True,
                                     **extra_fields)

    # Soft delete - models will be soft-deleted.
    SoftDeleteMixin = safedelete_mixin_factory(SOFT_DELETE,
                                               manager_superclass=UserManager)

    class User(SoftDeleteMixin, AbstractBaseUser, PermissionsMixin):
        """
        An abstract base class implementing a fully featured User model with
        admin-compliant permissions.

        Username, password and email are required. Other fields are optional.
        """
        first_name = models.CharField(_('first name'), max_length=30, null=True,
                                      blank=True)
        last_name = models.CharField(_('last name'), max_length=30, null=True,
                                     blank=True)
        email = models.EmailField(_('email address'), unique=True)
        is_staff = models.BooleanField(_('staff status'), default=False,
            help_text=_('Designates whether the user can log into this admin '
                        'site.'))
        is_active = models.BooleanField(_('active'), default=True,
            help_text=_('Designates whether this user should be treated as '
                        'active. Unselect this instead of deleting accounts.'))
        date_joined = models.DateTimeField(_('date joined'), default=timezone.now)

        # Additional fields

        USERNAME_FIELD = 'email'
        REQUIRED_FIELDS = []

        class Meta:
            app_label = 'myapp'
            verbose_name = _('User')
            verbose_name_plural = _('Users')

        def get_full_name(self):
            """
            Returns the first_name plus the last_name, with a space in between.
            """
            full_name = '%s %s' % (self.first_name, self.last_name)
            return full_name.strip()

        def get_short_name(self):
            "Returns the short name for the user."
            return self.first_name

        def email_user(self, subject, message, from_email=None, **kwargs):
            """
            Sends an email to this User.
            """
            send_mail(subject, message, from_email, [self.email], **kwargs)

why?

Without the change migrations (./manage.py makemigrations) fail. The traceback:

Traceback (most recent call last):
  File "./manage.py", line 10, in <module>
    execute_from_command_line(sys.argv)
  File "/home/user/.virtualenvs/myenv/lib/python3.4/site-packages/django/core/management/__init__.py", line 338, in execute_from_command_line
    utility.execute()
  File "/home/user/.virtualenvs/myenv/lib/python3.4/site-packages/django/core/management/__init__.py", line 330, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/home/user/.virtualenvs/myenv/lib/python3.4/site-packages/django/core/management/base.py", line 393, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/home/user/.virtualenvs/myenv/lib/python3.4/site-packages/raven/contrib/django/management/__init__.py", line 41, in new_execute
    return original_func(self, *args, **kwargs)
  File "/home/user/.virtualenvs/myenv/lib/python3.4/site-packages/django/core/management/base.py", line 444, in execute
    output = self.handle(*args, **options)
  File "/home/user/.virtualenvs/myenv/lib/python3.4/site-packages/django/core/management/commands/makemigrations.py", line 99, in handle
    ProjectState.from_apps(apps),
  File "/home/user/.virtualenvs/myenv/lib/python3.4/site-packages/django/db/migrations/state.py", line 178, in from_apps
    model_state = ModelState.from_model(model)
  File "/home/user/.virtualenvs/myenv/lib/python3.4/site-packages/django/db/migrations/state.py", line 441, in from_model
    reconstruct_manager(model._default_manager)
  File "/home/user/.virtualenvs/myenv/lib/python3.4/site-packages/django/db/migrations/state.py", line 425, in reconstruct_manager
    as_manager, manager_path, qs_path, args, kwargs = mgr.deconstruct()
  File "/home/user/.virtualenvs/myenv/lib/python3.4/site-packages/django/db/models/manager.py", line 110, in deconstruct
    % (name, module_name)
ValueError: Could not find manager SafeDeleteManager in safedelete.managers.
Please note that you need to inherit from managers you dynamically generated with 'from_queryset()'.

[Gagaro]

Thanks for the fix 👍 .

[Gagaro]

Released in 0.3.2

[barseghyanartur]

@Gagaro:

Thanks for the quick release!