Django CreateView does not save object

Question

I'm trying to use a Create View class in a Django App, but can't save the object. I tried some suggestions posted in related questions here and here with no results.

The error is

NoReverseMatch at /metas/add-meta Reverse for 'metas_detalle' with arguments '()' and keyword arguments '{'pk': None}' not found. 1 pattern(s) tried: ['metas/(?P\\d+)/control$']

The form is working and valid, the class call the save() method but the object isn't save, so, the id is None .

This is my models.py :

class MetasSPE(models.Model):
    puesto = models.CharField("Cargo", max_length=6, choices=PUESTOS)
    clave = models.CharField("Clave de la Meta", max_length=2)
    nom_corto = models.CharField('Identificación', max_length=25)
    year = models.PositiveIntegerField("Año")
    evaluacion = models.BooleanField('Evaluación', default=True)
    ciclos = models.PositiveSmallIntegerField('Repeticiones')
    descripcion = models.TextField('Descripción de la Meta')
    descripcion_html = models.TextField(
        'Descripción de la Meta', editable=False)
    soporte = models.FileField(
        'Soporte', upload_to=archivo_soporte, blank=True, null=True)
    usuario = models.ForeignKey(User, related_name='meta_user', editable=False)
    creacion = models.DateTimeField(auto_now_add=True)
    actualiza = models.DateTimeField(auto_now=True)

    def get_absolute_url(self):
        from django.core.urlresolvers import reverse
        return reverse('metas_detalle', kwargs={'pk': self.id})

The get_absolute_url() is working, tested in python manage.py shell :

In [1]: from django.core.urlresolvers import reverse

In [2]: reverse('metas_detalle', kwargs={'pk': 1})
Out[2]: '/metas/1/control'

This is the forms.py :

class MetasSPEForm(forms.ModelForm):
    class Meta:
        model = MetasSPE
        fields = ("puesto", "clave", "nom_corto", "evaluacion", "ciclos", "descripcion", "soporte")

And this is my views.py :

class CrearMeta(CreateView):
    model = MetasSPE
    form_class = MetasSPEForm
    template_name = 'metas/form_base.html'

    def form_valid(self, form):
        form.instance.usuario = self.request.user
        form.instance.year = 2015
        return super(CrearMeta, self).form_valid(form)

The urls.py looks like this:

urlpatterns = patterns(
    'metas.views',
    url(r'^$', 'home', name='metas_index'),

    url(r'^(?P<pk>\d+)/control$', MetaDetalle.as_view(), name='metas_detalle'),
    url(r'^add-meta$', 'agregar_meta', name='metas_add'),
)

By the way, I tried this function, and got the exact same error, but I'm unable to see the cause:

# from annoying.decorators import render_to
# from django.contrib.auth.decorators import login_required

@login_required
@render_to('metas/form_base.html')
def agregar_meta(request):
    if request.method == 'POST':
        form = MetasSPEForm(request.POST, request.FILES)
        if form.is_valid():
            meta = form.save(commit=False)
            meta.usuario = request.user
            meta.year = 2015
            meta.save()
            return redirect('metas_detalle', kwargs={'pk': meta.id})
    else:
        form = MetasSPEForm()
    return {'title': 'Agregar nueva meta', 'form': form}

Hope you can help me.

Answer 1

According to the error, you have the following URL pattern defined:

metas/(?P\\d+)/control$

...which should be metas/(?P<pk>\\d+)/control$

Note that this is different from the given patterns above:

urlpatterns = patterns(
    'metas.views',
    url(r'^$', 'home', name='metas_index'),

    url(r'^(?P<pk>\d+)/control$', MetaDetalle.as_view(), name='metas_detalle'),
    url(r'^add-meta$', 'agregar_meta', name='metas_add'),
)

If I had to guess, you are doing something like the below in the root urls.py :

urlpatterns = patterns(
    '',
    url(r'^metas/', include('metas.urls')),
    # Bad line with bad regex below!
    url(r'metas/(?P\d+)/control$', MetaDetalle.as_view(), name='metas_detalle'),
)

Actually, I found the problem:

https://github.com/SGC-Tlaxcala/sgc-metas/blob/e5a6c8e7a54f833795c46d5ece438b219460bf47/src/metas/models.py#L167-L177

class MetasSPE(models.Model):
    ...
    def save(self, **kwargs):
        """
        Se sobre-escribe el método `save()` para guardar la descripción con html.
        :param kwargs: Parámetros en clave
        :return: nada
        """
        from markdown import markdown
        self.descripcion_html = markdown(
            self.descripcion, outpu_format='html5', lazy_ol=True
        )

    def __str__(self):
        ...

You forgot to call super() on your overidden save() method, which means your model will never save:

class MetasSPE(models.Model):
    ...
    def save(self, **kwargs):
        """
        Se sobre-escribe el método `save()` para guardar la descripción con html.
        :param kwargs: Parámetros en clave
        :return: nada
        """
        from markdown import markdown
        self.descripcion_html = markdown(
            self.descripcion, outpu_format='html5', lazy_ol=True
        )
        super(MetasSPE, self).save(**kwargs)