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Django - Can't access data from object in many to many relationship

In my Django project, I am trying to create a website that streams TV shows. Each show belongs in many categories, hence the use of many to many relations in my model. What I want to do with a certain page on my website is dynamically load a page of shows belonging to a specific category. However, all of my attempts have ended in failure as I am unable to figure out a way on how to access the actual category data from each show.
In views.py
def shows_in_category(request, category_slug):
category = get_object_or_404(Category, slug=category_slug)
showsall = theShow.objects.all()
shows = []
for show in showsall:
print(show.category.name, category.name)
if show.category.name == category.name:
shows.append(show)
print(shows)
return render(request, 'show/show_list_view.html', {'category':category, 'shows': shows})
In models.py
class Category(models.Model):
name = models.CharField(max_length=255, db_index=True)
slug = models.SlugField(max_length=255, unique=True)
class Meta:
verbose_name_plural = 'Categories'
def __str__(self):
return self.name
def get_absolute_url(self):
return reverse("theshowapp:shows_in_category", args=[self.slug])
class theShow(models.Model):
english_name = models.CharField(max_length=400)
show_type = models.CharField(max_length=200, blank=True)
is_active = models.BooleanField(default=False)
category = models.ManyToManyField(Category)
slug = models.SlugField(max_length=400,unique=True)
class Meta:
verbose_name_plural = 'Shows Series'
def __str__(self):
return self.english_name
In the template (show_list_view.html)
{% for show in shows %}
<script> console.log("I'm trying to get in")</script>
<script> console.log("{{ show.name }} {{show.category.name}}")</script>
<script> console.log("I'm in")</script>
<div class="row">
<div class="col-lg-4 col-md-6 col-sm-6">
<div class="product__item">
<div class="product__item__text">
<ul>
{% for genre in show.category %}
<li>{{ show.category }}</li>
{% endfor %}
</ul>
<h5>{{ show.english_name }}</h5>
</div>
</div>
</div>
</div>
{% endfor %}
Any insight on this matter would be much appreciated.

What you're doing here violates some of the best practices of Django and also isn't using the Django ORM to its full potential. Please replace the lines
showsall = animeShow.objects.all()
shows = []
for show in showsall:
print(show.category.name, category.name)
if show.category.name == category.name:
shows.append(show)
print(shows)
with
shows = animeShow.objects.filter(category__name=category.name)
Also in the template change <li>{{ show.category }}</li> to <li>{{ genre }}</li> since that's the iterating variable.

I read up a bit more on the many to many fields examples in Django's documentation and figured out that I should use this:
shows = animeShow.objects.all().filter(category__name=category)

Django load an imageField in a template

Essentially what I'm trying to do is load the thumbnail image from my Post model in my template.
models.py
class Post(models.Model):
objects = models.Manager() # The default manager.
published = PublishedManager() # Our custom manager.
STATUS_CHOICES = (
('draft', 'Draft'),
('published', 'Published'),
)
title = models.CharField(max_length=250)
slug = models.SlugField(max_length=250, unique_for_date='publish')
author = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE, related_name='blog_posts')
body = models.TextField()
publish = models.DateTimeField(default=timezone.now)
created = models.DateTimeField(auto_now_add=True)
updated = models.DateTimeField(auto_now=True)
status = models.CharField(max_length=10, choices=STATUS_CHOICES, default='draft')
thumbnail = models.ImageField(name="photo", upload_to='thumbnails/', null=True, default='default.png')
class Meta:
ordering = ('-publish',)
def __str__(self):
return self.title
def get_absolute_url(self):
return reverse('blog:post_detail', args=[self.publish.year, self.publish.month, self.publish.day, self.slug])
views.py
class PostListView(ListView):
queryset = Post.published.all()
context_object_name = 'posts'
paginate_by = 3
template_name = 'blog/post/list.html'
def get_context_data(self, **kwargs):
obj = Settings.objects.get(pk=1)
context = super().get_context_data(**kwargs)
context["blog_name"] = getattr(obj, "blog_name")
context["footer"] = getattr(obj, "footer")
context["description"] = getattr(obj, "description")
context["keywords"] = getattr(obj, "keywords")
return context
I added <img src="{{post.thumbnail.url}}" alt="{{ post.title }}"> to my template to try and load the image but no luck. I can access the image if I load the path manually and i already added MEDIA_URL and MEDIA_ROOT to my settings.py
If this question can be improved please let me know as I am knew to django.
template
<header>
<script
src="https://code.jquery.com/jquery-3.4.1.min.js"
integrity="sha256-CSXorXvZcTkaix6Yvo6HppcZGetbYMGWSFlBw8HfCJo="
crossorigin="anonymous"></script>
<script type='text/javascript'>
window.addEventListener('scroll', function() {$('#top-bar').width(Math.round($(document).scrollTop()/document.body.offsetHeight*100*1.1)+'%');});
</script>
<div id='top-bar'></div>
<h1 id='title'>{{ post.title }}</h1>
<p id='author-info'>Published {{ post.publish }} by {{ post.author }}</p>
</header>

One thing that I would check first is to make sure the URL is actually showing up correctly in the template. You can do that by just creating a dummy span like this:
<span>{{ post.thumbnail.url }}</span>
Put that somewhere, render the page and see what you get. Ensure that the URL is the correct URL. Sometimes when you're messing with media URLs and roots, things get a bit wonky.
UPDATE:
Based on your recent edits, I see two red flags: One is that you've got your body up in your header section. Two is that it doesn't appear that you're iterating through the list of objects that are being passed as context by your ListView. Your listview, as i interpret it, is passing a list of posts. If that's the case, your code should look something like this:
<header>
<script
src="https://code.jquery.com/jquery-3.4.1.min.js"
integrity="sha256-CSXorXvZcTkaix6Yvo6HppcZGetbYMGWSFlBw8HfCJo="
crossorigin="anonymous"></script>
<script type='text/javascript'>
window.addEventListener('scroll', function() {$('#top-bar').width(Math.round($(document).scrollTop()/document.body.offsetHeight*100*1.1)+'%');});
</script>
</header>
<body>
<div id='top-bar'></div>
{% for post in posts %}
<h1 id='title'>{{ post.title }}</h1>
<p id='author-info'>Published {{ post.publish }} by {{ post.author }}</p>
<img src="{{ post.thumbnail.url }}">
{% endfor %}
</body>
Still, there is something a bit off about your whole HTML document. You'll need to add in DIV elements or grid table elements to more appropriately render the above stuff.

Another thing: Since your'e using a list view, you might want to post a portion of your template code here in your question. As a list view, you have to ensure that you're properly looping through the object you're sending to the template as context.
Is everything else showing up in your template rendering as you intend? Is it just the image that isn't showing properly?

How to display post and related comments on single page?

I am unable to design a code to render one particular post and it's related comments. The issue is maybe in views.py or the url.
I have looked at multiple sources without any results. I am a novice to coding and feel like I am missing some essential point. Posts and comments are getting created correctly and all comments get the correct post_id assigned.
My models.py is set up like this:
class Post(models.Model):
title = models.CharField(max_length=1000)
content = models.TextField()
date_posted = models.DateTimeField(default=timezone.now)
author = models.ForeignKey(User, on_delete=models.CASCADE)
def __str__(self):
return self.title
def get_absolute_url(self):
return reverse('blog-home')
class Comment(models.Model):
cid = models.AutoField(primary_key=True)
author = models.ForeignKey(User, on_delete=models.CASCADE)
post = models.ForeignKey(Post, on_delete=models.CASCADE)
comment = models.TextField()
comment_date = models.DateTimeField(default=timezone.now)
def save(self, *args, **kwargs):
super(Comment, self).save(*args, **kwargs)
def __str__(self):
return self.comment
def get_absolute_url(self):
return reverse('blog-home')
My views.py is set up like this:
class PostDetailView(DetailView):
model = Post
def get_context_data(self, **kwargs):
context = super().get_context_data(**kwargs)
context['comment_list'] = Comment.objects.filter(post=WHAT SHOULD GO HERE?)
return context
I need to pass the Post.id or primary key of the post in the filter above. Can someone explain what it should be?
The url used to access the post detail is as follows:
path('post/<int:pk>/', PostDetailView.as_view(), name='post-detail')
I get the post detail view rendered out as the author, title and content of the post when I have the following in views.py:
class PostDetailView(DetailView):
model = Post
The template for that is as below:
{% extends "blog/base.html" %}
{% block content%}
<article class="media content-section">
<img class="rounded-circle article-img" src="{{object.author.profile.image.url}}">
<div class="media-body">
<div class="article-metadata">
<a class="mr-2" href="{% url 'user-posts' object.author.username %}">{{ object.author }}</a>
<small class="text-muted">{{ object.date_posted|date:"F d, Y P e" }}</small>
{% if object.author == user %}
<div><a class="btn btn-secondary btn-sm m-1 mb-1" href="{% url 'post-update' object.id%}">Update</a>
<a class="btn btn-danger btn-sm m-1 mb-1" href="{% url 'post-delete' object.id%}">Delete</a></div>
{% endif %}
</div>
<h2 class="article-title">{{ object.title }}</h2>
<p class="article-content">{{ object.content }}</p>
</div>
</article>
{% for comment in comment_list %}
<div class='article-content'>
<p>{{comment}}</p>
</div>
{% endfor %}
{% endblock %}
How should I take the post.id or pk of the Post and use it to filter the comments related only to that particular post?
Also, what is a good way to set up a template for rendering the queryset?

You should be able to iterate over the reverse link from Post object to the Comment objects linked to it (by default as comment_set) in your template:
{% for comment in post.comment_set %}
If you want greater control you inject a queryset into the context, something like this, to get the most recent six comments only.
"comments": post.comment_set.order_by("-comment_date")[:6]
The post object selected should be available as self.object in a DetailView and will be default be injected into the render context as object. An invaluable resource for navigating the structure of Django Class-based views is the Classy CBV
site.
Warning: this is "off the top of my head" so don't assume it's all perfect.

A single object will have access to its related objects.
Try this:
class PostDetailView(DetailView):
model = Post
# There's no need to define get_context_data() here
Now your template will have the post available as post (and also object).
All of the comments that have this post are available on the template like this:
{% for comment in post.comment_set.all %}
<div class='article-content'>
<p>{{ comment }}</p>
</div>
{% endfor %}

Related Objects Reference Django

Given the following code:
Models.py
class Advertisement(models.Model):
title = models.CharField(null=True, blank=True, max_length=30)
created_by = models.ForeignKey(User)
class Gallery(models.Model):
advertisement = models.ForeignKey(Advertisement, related_name='images')
image = models.ImageField(upload_to=image_directory_path, help_text="Your ad image (Recommended size: 1024x768)")
creation_date = models.DateTimeField(editable=False, default=timezone.now)
Views.py
def do_foo(request):
search_result = Advertisement.objects.all().order_by('-creation_date')
return render(request, 'content_search.html',
{
'search_result': search_result
})
page.html
{% for ad in search_result %}
{% for ad_image in ad.gallery_set %}
<img src="{{ ad_image.image.url }}">
{% endfor %}
{% endfor %}
How do I access the backwards relation between Advertisement and Gallery? I tried ad.gallery_set and ad.images_set but I could not get the images.
I tried to follow what they say here Django Relation Objects Reference and in this topic.

Your code has related_name="images". So ad.images it is.
Edit: as shredding notes correctly, you can't use that directly if you want to loop over it, and need to add .all to get a queryset object:
{% for ad_image in ad.images.all %}
<img src="{{ ad_image.image.url }}">
{% endfor %}
Maybe related name "galleries" would be a bit more clear.

Django: Check that row exists in list

I want to check that user_id exists in the profile_images table from my Django template.
My Model
class profiles(models.Model):
profile_id = models.AutoField(primary_key=True)
user = models.ForeignKey(User)
-----
class Profile_images(models.Model):
id = models.AutoField(primary_key=True)
user = models.ForeignKey(User)
image = models.ImageField(upload_to='uploads/',default = 'uploads/no-img.jpg')
My View
def view_profiles(request):
if request.user.is_authenticated():
view_all_profiles = profiles.objects.all()
profile_image = Profile_images.objects.all()
return render_to_response('profiles/all.html', {'profiles':view_all_profiles,'profile_image':profile_image}, context_instance=RequestContext(request),)
else:
return HttpResponseRedirect('/accounts/login/')
My Template
{% for profile in profiles %}
<li>
{% for image in profile_image %}
{% ifequal image.user_id profile.user_id %}
<img src="{{MEDIA_URL}}{{image.image}}" alt="image" />
{% endifequal %}
<!-- i want to check here if not user_id exist in profile_images table -->
{% if profile.user_id not in profile_image %}
<img src="{% static 'images/no-image.jpg' %}" alt="image" />
{% endif %}
{% endfor %}
</li>
{% endfor %}
{% if profile.user_id not in profile_image %} is not working. I'm new to Django & python and I'm stuck here. Please suggest better ways if my code is not correct.

in your view you could get all user_ids with a profile image, something like:
user_ids_with_profile_images = Profile_images.objects.all().values_list('user_id', flat=True)
Then in your template you could check if profile.user_id not in user_ids_with_profile_images.
It might actually be a little cleaner to loop through all the users with profiles in your system and get their profile images through the foreign key, instead of looping through all the profiles and trying to get the users...

This is really a design problem, you've got a separate model specifically for a profile image when that could just be a field on the profile model itself.
class Profile(models.Model): # convention is to use a non-plural name for models
# No need to explicitly set the primary key, this will be added automatically
# profile_id = models.AutoField(primary_key=True)
user = models.ForeignKey(User)
image = models.ImageField(upload_to='uploads/',default = 'uploads/no-img.jpg')
-----
Now it would just be a case of using {{ profile.image }} with no need for any additional looking up.