Recursively going through a model - django

Question

I have a model like so:
class CustomUser(models.Model):
user = models.OneToOneField(User, on_delete=models.CASCADE)
slug = models.SlugField(blank=True)
def lastfolder(self):
try:
return self.folder_set.all().order_by('-created_at')[0]
except IndexError:
return None
def lastdrive(self):
try:
return self.drive_set.all().order_by('-created_at')[0]
except IndexError:
return None
def lastfile(self):
try:
return self.drive_set.all().order_by('-created_at')[0]
except IndexError:
return None
def save(self, *args, **kwargs):
self.slug = slugify(self.user.username)
return super().save(*args, **kwargs)
def get_absolute_url(self):
kwargs = {'slug' : self.slug}
return reverse('', kwargs=kwargs)
def __str__(self):
return self.user.username
class Drive(models.Model):
owner = models.ForeignKey(CustomUser, on_delete=models.CASCADE)
name = models.CharField(max_length=64)
cover_picture = models.ImageField(upload_to=f'media/{user_path}', default="media/drive.png")
created_at = models.DateTimeField()
slug = models.SlugField(blank=True)
def get_absolute_url(self):
kwargs = {'slug' : self.slug}
return reverse('', kwargs=kwargs)
def __str__(self):
return self.name
def save(self, *args, **kwargs):
self.slug = slugify(self.name)
return super().save(*args, **kwargs)
class Meta:
unique_together = [['owner', 'name']]
ordering = ('name',)
class Folder(models.Model):
owner = models.ForeignKey(CustomUser, on_delete=models.CASCADE)
drive = models.ForeignKey('Drive', on_delete=models.CASCADE)
name = models.CharField(max_length=64)
parent = models.ForeignKey('self', on_delete=models.CASCADE, blank=True, null=True)
cover_picture = models.ImageField(upload_to=f'media/{user_path}', default="media/folder-white.png")
created_at = models.DateTimeField()
path = models.CharField(max_length=2048, blank=True)
slug = models.SlugField(blank=True)
def __str__(self):
return self.name
def get_absolute_url(self):
kwargs = {'slug' : self.slug}
return reverse('', kwargs=kwargs)
def get_path(self):
yield self.name
try:
yield from get_path(self.parent)
except:
pass
def complete_get_path(self):
text = []
for i in self.get_path():
text.append(i)
text.reverse()
return "/".join(text)
def save(self, *args, **kwargs):
self.slug = slugify(self.name)
self.path = self.complete_get_path()
return super().save(*args, **kwargs)
class Meta:
unique_together = [['parent', 'name']]
ordering = ('name',)
If I create a Folder instance with a name Programming and another Folder instance with a name Python and parent with reference to Programming, it is supposed to populate the path field for Programming with "Programming" and Python with "Programming/Python". Unfortunately, it does not work
My emphasis is on the Folder model and the methods: get_path, complete_get_path, and save.
After saving the model, and checking the path field in the admin, it just shows only the name attribute not return the actual generated path of the folder.
How do I go about it.

Answer 1

The problem is that get_path isn't defined and the blanket try/except is eating your error. Your method should be:
def get_path(self):
yield self.name
yield from self.parent.get_path()
Here's a slight optimization. If you yield the parent's path's first, you don't have to reverse the list of folder names and then can simply join it at the end.
def get_path(self):
yield from self.parent.get_path()
yield self.name
def complete_get_path(self):
return "/".join(self.get_path())