Django get_absolute_url always throwing a 404 - django

Question

I am building a Django project ( 1.8) and am having trouble using get_absolute_url method of one of my models. I populated my database with some posts, so I could check my application. I am able to list the database objects in one of my views, so I know that the objects are there, and my app can display them. The problem comes when I click a link, and the view always returns a 404 ( basically It can't find an object to display)
Below is most of the code from this app. I tried to include my imports in these snippets, but truncated some of it to keep the post short.
valueFact/models.py
class ValueFactPost(models.Model):
STATUS_CHOICE = (
('draft', 'Draft'),
('published', 'Published')
)
title = models.CharField(max_length=250)
slug = models.SlugField(max_length=250, unique_for_date='publish')
author = models.ForeignKey(User, related_name='valueFact_posts')
publish = models.DateTimeField(default=timezone.now)
body = models.TextField()
created = models.DateTimeField(auto_now_add=True)
updated = models.DateTimeField(auto_now=True)
status = models.CharField(max_length=10,
choices=STATUS_CHOICE,
default='draft')
stockSymbol = models.ForeignKey('Symbol', null=True )
objects = models.Manager()
published = ValueFactManager()
def get_absolute_url(self):
return reverse('companies:valuefact_detail', args=[self.publish.year,
self.publish.strftime('%m'),
self.publish.strftime('%d'),
self.slug])
urls.py
from django.conf.urls import include, url
urlpatterns = [
url(r'^admin/', include(admin.site.urls)),
url(r'^companies/', include('valueFact.urls', namespace='companies', app_name='companies')),
]
valueFact/urls.py
from django.conf.urls import url
from . import views
urlpatterns = [
url(r'^$', views.valueFactListView.as_view(), name='valueFact_list'),
url(r'^(?P<year>\d{4})/(?P<month>\d{2})/(?P<day>\d{2})/(?P<post>[-\w]+)/$',
views.valuefact_detail,
name='valuefact_detail'),
]
valueFact/views.py
from django.shortcuts import render, get_object_or_404, render_to_response
from valueFact.models import ValueFactPost, Symbol
class valueFactListView(ListView):
queryset = ValueFactPost.published.all()
context_object_name = 'valueFacts'
paginate_by = 2
template_name = 'companies/valueFact/list.html'
def valuefact_detail(request, year, month, day, post):
post = get_object_or_404(ValueFactPost, slug=post,
status='published',
publish__year=year,
publish__month=month,
publish__day=day)
return render(request, 'companies/valuefact/detail.html', {'post':post})
The template where the problem seems to occur:
list.html
{% for post in valueFacts %}
<a href="{{ post.get_absolute_url }}">
{{ post.title}}
</a>
</h2>
<p class="date">
Published {{post.publish}} by {{post.author}}
</p>
{{post.body|truncatewords:30|linebreaks}}
{% endfor %}**
The error in the django console is : Not Found: /companies/2016/03/23/seadrill-debt/
I have spent an inordinate amount of time on this issue which would probably take someone a couple of minutes to fix. Thanks in advance.

Answer 1

Do you have PYTZ installed? I can't guarantee this is the answer, but it's worth a try. I don't see anything wrong with the code, as I'm using pretty much the same code in a project.

Answer 2

If you use different timezone than UTC, when an object is saved, publish attribute can be different than when you have UTC timezone.
If that's the case your get_absolute_url method has to return localtime version of publish.
In your models.py, consider writing like this
def get_absolute_url(self):
"""
Get single object.
year, month, day, and slug order.
"""
# convert to Asia/seoul time
localdatetime = timezone.localtime(self.publish)
return reverse(
"blog:post_detail",
args=[
localdatetime.year,
localdatetime.month,
localdatetime.day,
self.slug,
],
)
SO has other similar post regarding this.

Answer 3

Method 1:
Instead of using DateTimeField use DateField in your model and the problem will be solved.
# models.py
class Post(models.Model):
publish = models.DateField(default=timezone.now)
created = models.DateField(auto_now_add=True)
updated = models.DateField(auto_now=True)
Method 2: Override get_object

Answer 4

Your url pattern establishes 4 keyword arguments:
year
month
day
post
but your call to reverse is passing those values in as positional arguments (args), which is a list. Instead, pass them in as keyword arguments (kwargs), which is a dictionary:
def get_absolute_url(self):
return reverse('companies:valuefact_detail', args=[],
kwargs={
'year':self.publish.year,
'month': self.publish.strftime('%m'),
'day': self.publish.strftime('%d'),
'post': self.slug
})