When i'm trying to add a Post through django admin i get an error that the Post im trying to add needs to have a value for field id. Do you have any idea why?
now = datetime.now()
class Category(models.Model):
name = models.CharField(max_length=200)
slug = models.SlugField(unique=True)
class Meta:
verbose_name_plural = "categories"
def __str__(self):
return self.name
class Post(models.Model):
title = models.CharField(max_length=100)
excerpt = models.CharField(max_length=200)
main_image = models.ImageField()
author = models.ForeignKey(users.models.CustomUser, on_delete=models.CASCADE, related_name='blog_posts', null=True)
content = models.TextField(null=True)
created_at = models.DateTimeField(editable=False)
updated_at = models.DateTimeField(editable=False)
category = models.ManyToManyField(Category, related_name='post_category')
class Meta:
ordering = ['-created_at']
def save(self, *args, **kwargs):
if not self.id:
self.created_at = now
self.updated_at = now
def __str__(self):
return self.title
CodePudding user response:
You need to make a super().save(*args, **kwargs)
call. Furthermore using a constant will not work: this will assign the time when you started the server, not the current time, so:
from django.utils.timezone import now
class Post(models.Model):
# …
def save(self, *args, **kwargs):
if not self.id:
self.created_at = now()
self.updated_at = now()
super().save(*args, **kwargs)
You furthermore do not need to specify logic to update the created_at
and updated_at
field, you can work with auto_now_add=True
[Django-doc] and auto_now=True
[Django-doc]:
class Post(models.Model):
# …
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now=True)
# …
class Meta:
ordering = ['-created_at']
# no save override
def __str__(self):
return self.title