Python django.db.models.PROTECT Examples

The following are 6 code examples of django.db.models.PROTECT(). You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example. You may also want to check out all available functions/classes of the module django.db.models , or try the search function .
Example #1
Source File: patches.py    From django-more with BSD 3-Clause "New" or "Revised" License 7 votes vote down vote up 
def ask_remove_enum_values(self, db_type, values):
        """ How to treat records with deleted enum values. """
        # Ordered ensures
        choices = [
            (models.CASCADE, "Cascade - Delete records with removed values"),
            (models.PROTECT, "Protect - Block migrations if records contain removed values"),
            (models.SET_NULL, "Set NULL - Set value to NULL"),
            (models.SET_DEFAULT, "Set default - Set value to field default"),
            (models.SET, "Set value - Provide a one off default now"),
            (models.DO_NOTHING, "Do nothing - Consistency must be handled elsewhere"),
            (None, "Leave it to field definitions")]
        choice, _ = choices[self._choice_input(
            "Enum {db_type} has had {values} removed, "
            "existing records may need to be updated. "
            "Override update behaviour or do nothing and follow field behaviour.".format(
                db_type=db_type,
                values=values),
            [q for (k, q) in choices]) - 1]
        if choice == models.SET:
            return models.SET(self._ask_default())
        return choice
Example #2
Source File: operations.py    From django-more with BSD 3-Clause "New" or "Revised" License 5 votes vote down vote up 
def __init__(self, db_type, add_values=None, remove_values=None, on_delete=models.PROTECT):
        self.db_type = db_type
        self.add_values = set(add_values or ())
        self.remove_values = set(remove_values or ())
        self.on_delete = on_delete
Example #3
Source File: snapshots.py    From Politikon with GNU General Public License v2.0 5 votes vote down vote up 
def create_snapshot_model(cls, fields=[]):
    """ Dynamically create a main Model, 1-1 with the model being snapshotted. """
    # Models must have unique names, so we create a name by suffixing model class name with 'Snapshot'
    name = cls.__name__ + 'Snapshot'

    class Meta:
        db_table = '%s_snapshot' % cls._meta.db_table
        app_label = cls._meta.app_label
        verbose_name = u'%s - snapshot' % cls._meta.verbose_name
        verbose_name_plural = u'%s - snapshoty' % cls._meta.verbose_name
        ordering = ['-created_at']

    # Set up a dictionary to simulate declarations within a class.
    attrs = {
        '__module__': cls.__module__,
        'Meta': Meta,
        'id': models.AutoField(primary_key=True),
        'created_at': models.DateTimeField(u"stworzony dnia", auto_now_add=True),
        'snapshot_of': models.ForeignKey(cls, verbose_name=u"dotyczy", null=False, on_delete=models.PROTECT, related_name="snapshots"),
        '__unicode__': lambda self: u'snapshot',
    }

    # Copy fields
    for field_name in fields:
        target_field = cls._meta.get_field_by_name(field_name)[0]
        attrs[field_name] = copy_field(target_field)

    return type(name, (models.Model,), attrs)
Example #4
Source File: views.py    From wagtail with BSD 3-Clause "New" or "Revised" License 5 votes vote down vote up 
def post(self, request, *args, **kwargs):
        try:
            msg = _("%(model_name)s '%(instance)s' deleted.") % {
                'model_name': self.verbose_name, 'instance': self.instance
            }
            self.delete_instance()
            messages.success(request, msg)
            return redirect(self.index_url)
        except models.ProtectedError:
            linked_objects = []
            fields = self.model._meta.fields_map.values()
            fields = (obj for obj in fields if not isinstance(
                obj.field, ManyToManyField))
            for rel in fields:
                if rel.on_delete == models.PROTECT:
                    if isinstance(rel, OneToOneRel):
                        try:
                            obj = getattr(self.instance, rel.get_accessor_name())
                        except ObjectDoesNotExist:
                            pass
                        else:
                            linked_objects.append(obj)
                    else:
                        qs = getattr(self.instance, rel.get_accessor_name())
                        for obj in qs.all():
                            linked_objects.append(obj)
            context = self.get_context_data(
                protected_error=True,
                linked_objects=linked_objects
            )
            return self.render_to_response(context)
Example #5
Source File: views.py    From wagtailmodeladmin with MIT License 5 votes vote down vote up 
def post(self, request, *args, **kwargs):
        if request.POST:
            try:
                self.delete_instance()
                messages.success(
                    request,
                    _("{model} '{instance}' deleted.").format(
                        model=self.model_name, instance=self.instance))
                return redirect(self.get_index_url)
            except models.ProtectedError:
                messages.error(
                    request, _(
                        "{model} '{instance}' could not be deleted."
                    ).format(model=self.model_name, instance=self.instance))

                linked_objects = []
                for rel in self.model._meta.get_all_related_objects():
                    if rel.on_delete == models.PROTECT:
                        qs = getattr(self.instance, rel.get_accessor_name())
                        for obj in qs.all():
                            linked_objects.append(obj)

                context = {
                    'view': self,
                    'instance': self.instance,
                    'error_protected': True,
                    'linked_objects': linked_objects,
                }
        return self.render_to_response(context)
Example #6
Source File: models.py    From jorvik with GNU General Public License v3.0 5 votes vote down vote up 
def media_consumi(self):
        rifornimenti = Rifornimento.objects.filter(veicolo=self)
        litri = 0
        for rifornimento in rifornimenti:
            litri += rifornimento.consumo_carburante
        try:
            ultimo_rifornimento = Rifornimento.objects.filter(veicolo=self).latest("data")
            primo_rifornimento = Rifornimento.objects.filter(veicolo=self).earliest("data")
        except Rifornimento.DoesNotExist:
            return 0
        km = ultimo_rifornimento.contachilometri - primo_rifornimento.contachilometri
        litri -= ultimo_rifornimento.consumo_carburante
        if litri != 0:
            return round(km/litri, 2)
        else:
            return 0

# class Immatricolazione(ModelloSemplice, ConMarcaTemporale):
#     """
#     Rappresenta una pratica di immatricolazione di un Veicolo
#
#     Una pratica viene istruita da un ufficio motorizzazione per conto di una unita' CRI richiedente.
#     La stessa viene sottoposta a due stadi di approvazione, in seguito alla istruzione. Quando la
#     pratica termina, il veicolo viene immatricolato ed entra in servizio.
#     """
#
#     class Meta:
#         verbose_name = "Pratica di Immatricolazione"
#         verbose_name_plural = "Pratiche di Immatricolazione"
#
#     richiedente = models.ForeignKey(Sede, related_name='immatricolazioni_richieste', null=True, on_delete=models.SET_NULL)
#     ufficio = models.ForeignKey(Sede, related_name='immatricolazioni_istruite', on_delete=models.PROTECT)
#     veicolo = models.ForeignKey(Veicolo, related_name='richieste_immatricolazione', on_delete=models.CASCADE)