问题内容
我有一个页面模型，在保存对象期间调用 save 方法中的打印。但是，当对象被删除时，不会触发任何打印，并且似乎永远不会调用删除方法。那么我应该如何覆盖默认的删除方法呢？
class Page(models.Model):
image = models.ImageField()
number = models.PositiveIntegerField(default=0, blank=True, null=True)
chapter = models.ForeignKey(Chapter, on_delete=models.CASCADE)
def get_upload_path(self, filename):
work_slug = self.chapter.volume.work.slug
translator_name = slugify(self.chapter.volume.translator)
volume_number = self.chapter.volume.number
chapter_number = self.chapter.number
name, extension = filename.rsplit('.', 1)
return f'media/{work_slug}/{translator_name}/volumes/volume-{volume_number}/chapters/chapter-{chapter_number}/page-{self.number}.{extension}'
def save(self, *args, **kwargs):
if not self.pk:
last_page = self.chapter.page_set.last()
if last_page:
self.number = last_page.number + 1
self.image.name = self.get_upload_path(self.image.name)
self.image.storage = s3
print(f"Saving Page with image: {self.image.name}")
super().save(*args, **kwargs)
def delete(self, *args, **kwargs):
print(f"Deleting Page with image: {self.image.name}")
image_name = self.image.name
try:
s3.delete(image_name)
print(f"Successfully deleted from S3: {image_name}")
except Exception as e:
print(f"Error deleting from S3: {e}")
super().delete(*args, **kwargs)正确答案
删除一个对象时调用 model 的 delete 方法。如果您尝试删除查询集（例如从 django 管理列表页面删除），您必须覆盖模型的查询集。
class PageQuerySet(models.QuerySet):
def delete(self):
print("deleting queryset")
return super().delete()
class PageManager(models.Manager):
def get_queryset(self):
return PageQuerySet(model=self.model, using=self._db, hints=self._hints)
class Page(models.Model):
image = models.ImageField()
number = models.PositiveIntegerField(default=0, blank=True, null=True)
chapter = models.ForeignKey(Chapter, on_delete=models.CASCADE)
objects = PageManager()
def get_upload_path(self, filename):
work_slug = self.chapter.volume.work.slug
translator_name = slugify(self.chapter.volume.translator)
volume_number = self.chapter.volume.number
chapter_number = self.chapter.number
name, extension = filename.rsplit('.', 1)
return f'media/{work_slug}/{translator_name}/volumes/volume-{volume_number}/chapters/chapter-{chapter_number}/page-{self.number}.{extension}'
def save(self, *args, **kwargs):
if not self.pk:
last_page = self.chapter.page_set.last()
if last_page:
self.number = last_page.number + 1
self.image.name = self.get_upload_path(self.image.name)
self.image.storage = s3
print(f"Saving Page with image: {self.image.name}")
super().save(*args, **kwargs)
def delete(self, *args, **kwargs):
print(f"Deleting Page with image: {self.image.name}")
image_name = self.image.name
try:
s3.delete(image_name)
print(f"Successfully deleted from S3: {image_name}")
except Exception as e:
print(f"Error deleting from S3: {e}")
super().delete(*args, **kwargs) 
