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How can I link a comment to its corresponding post in Django?

I am building a Django project where I have an index page that lists all posts. The user can click on the name of a post and this will take them to a detail page with the complete post information (date, content, category). This detail page also has a link that will take the user to a form where they can leave a comment. Once the user clicks submit they are supposed to navigate back to the post detail page and the comment is supposed to be there. The issue I am having right now is that the comment is being automatically assigned to the first post in the index list rather than the post the user had visited (I think this may have something to do with the current default setting in my models, but how else can I get the post id?). How can I make it so that the comment is assigned to its correct post? I have tried everything with the models and views but nothing seems to work. Thank you for your help, I think the solution to this might be simple but I can't find it anywhere.
Here is my relevant models:
class UserPost(models.Model):
title = models.CharField(max_length=255)
category = models.ForeignKey('Category', on_delete=models.SET_NULL, null=True)
content = models.TextField()
created_on = models.DateTimeField(auto_now_add=True)
author = models.ForeignKey(User, default=1,
on_delete = models.CASCADE
)
#id = models.AutoField(primary_key=True)
def __str__(self):
"""String for representing the UserPost object."""
return self.title
def get_absolute_url(self):
"""Returns the url to access a detail record for this user post."""
return reverse('userpost-detail', args=[str(self.id)])
class Comment(models.Model):
author = models.ForeignKey(User, default=1,
on_delete = models.CASCADE
)
content = models.TextField()
created_on = models.DateTimeField(auto_now_add=True)
def comment_default():
return {UserPost.id}
post = models.ForeignKey(UserPost, default= comment_default, on_delete=models.CASCADE, related_name="comments")
def __str__(self):
"""String for representing the comment object."""
return '%s - %s - %s' % (self.post.title, self.author, self.created_on)
def get_absolute_url(self):
return reverse('userpost-detail', args=[str(self.post.id)])
And my views:
class UserPostDetailView(generic.DetailView):
model = UserPost
#post = UserPost.objects.get(id=id)
#comments = Comment.objects.filter(Comment.post)
def get_context_data(self, **kwargs):
context = super(UserPostDetailView, self).get_context_data(**kwargs)
context['Comment'] = UserPost.comments
return context
class PostCreate(CreateView):
model = UserPost
fields = ['title', 'category', 'content']
class CommentCreate(CreateView):
model = Comment
fields = ['post','content']
And my html:
{% extends "base.html" %}
{% block page_content %}
<h1>Title: {{ userpost.title }}</h1>
<p><strong>Author:</strong> {{ userpost.author }}</p>
<p><strong>Content:</strong> {{ userpost.content }}</p>
<p><strong>Category:</strong> {{ userpost.category }}</p>
<a class="btn btn-primary" href="{% url 'comment-create' %}" role="button">Leave a Comment</a>
<h3>Comments:</h3>
{% for comment in userpost.comments.all %}
<p>
On {{comment.created_on.date }}
<b>{{ comment.author }}</b> wrote:
</p>
<p>{{ comment.content }}</p>
<hr>
{% endfor %}
{% endblock %}

You need to pass Post ID in your url for this.
path("comment/<int:post_id>/", CommentCreateView, name="comment-create")
Now in template
<a class="btn btn-primary" href="{% url 'comment-create' userpost.id %}" role="button">Leave a Comment</a>
Views
class CommentCreateView(CreateView):
model = Comment
fields = ['content'] # remove field post here
def form_valid(self, form):
form.instance.post_id = self.kwargs.get("post_id")
return super().form_valid(form)

How do i query for comment in Django

I am new in Django and I have been following tutorials online. I am having problem on how to display the comments.
How do i query for comments in views, so i can display comments for a particular post.
Model:
class Post(models.Model):
poster_profile = models.ForeignKey(settings.AUTH_USER_MODEL,on_delete=models.CASCADE, blank=True,null=True)
image_caption = models.TextField(blank=True, null=True)
class Comments (models.Model):
user = models.ForeignKey(settings.AUTH_USER_MODEL,on_delete=models.CASCADE, blank=True,null=True)
commented_image = models.ForeignKey(Post, on_delete=models.CASCADE, null=True, blank=True)
comment_post = models.TextField()
Views.py:
def home_view(request):
comment = Comments.objects.all() #This is getting all comment in all post, how do i query for comment in a particular post.
context{'comment':comment}
return render(...)
Template:
{% for com in comment %}
<p>{{ com.comment_post }}</p>
{% endfor %}

You can do
post = Post.objects.get(id=1)
comment = post.comments_set.all()
Following Relationships "Backward"
If a model has a ForeignKey, instances of the foreign-key model will have access to a Manager that returns all instances of the first model. By default, this Manager is named FOO_set, where FOO is the source model name, lowercased. This Manager returns QuerySets, which can be filtered and manipulated as described in the “Retrieving objects” section above.
Note this behaviour can be overridden.
You can override the FOO_set name by setting the related_name parameter in the ForeignKey definition. For example, if the Entry model was altered to blog = ForeignKey(Blog, on_delete=models.CASCADE, related_name='entries'), the above example code would look like this:
Edit #2:
views.py:
def home_view(request):
posts = Post.objects.all().reverse()[5]
context{ 'posts': posts, }
return render(...)
Now in your templates you can do something like:
{% if posts %}
{% for post in posts %}
{{ post.image_caption }}
{% for comment in post.comments_set.all %}
{{ comment.comment_post }}
{% endfor %}
{% endfor %}
{% endif %}

First of all, take a look at Django queryset documentation, especially select_related for this kind of issues (to reduce number of queries to database). I didn't try but following snippet must work.
class Post(models.Model):
poster_profile = models.ForeignKey(settings.AUTH_USER_MODEL,on_delete=models.CASCADE)
image_caption = models.TextField(blank=True, null=True)
class Comments (models.Model):
user = models.ForeignKey(settings.AUTH_USER_MODEL,on_delete=models.CASCADE)
commented_image = models.ForeignKey(Post, related_nam="comments", on_delete=models.CASCADE)
comment_post = models.TextField()
...
def home_view(request):
post = Post.objects.filter(id=request.data.get('post_id')).select_related("comments") # specify the post anyhow ..
comments = post.comments
context{'comment': comments}
return render(...)

def home_view(request):
particular_Post= Post.objects.get(id=1)
comment = Comments.objects.get(Post=particular_Post)
context{'comment':comment}
return render(...)
to understund Query in django i suggest U to start by
python manage.py shell
and Import you're Models

How to create a form field for every foreignkey in manytomany relationship in Django

I don't understand how to build a specific form in Django.
First of all here are my models:
class Category(models.Model):
name = models.CharField(max_length=200, unique=True)
class Assessment(models.Model):
name = models.CharField(max_length=200)
pub_date = models.DateTimeField(verbose_name=_('date published'), default=timezone.now)
classgroup = models.ForeignKey(ClassGroup, verbose_name=_('class'), on_delete=models.CASCADE, related_name='+')
category = models.ManyToManyField(Category, through='AssessmentScale', through_fields=('assessment', 'category'),)
total = models.IntegerField()
class AssessmentScale(models.Model):
assessment = models.ForeignKey(Assessment, on_delete=models.CASCADE)
category = models.ForeignKey(Category, on_delete=models.CASCADE)
value = models.IntegerField()
I would like to have a form like this html form. Actually, an assessment scale is sub-divided into different categories. So when I create an assessment, I'd like have a form field for each category allowing to add a value via my custom intermediary model AssessmentScale. But I really don't know the Django way to build this form. I read this post, which is similar I think, and someone advised the use of Inline model formsets. But I don't understand how to solve my problem with the latter. Could you help me?

I had no answer from Stackoverflow but a friend of mine solved my problem like this with inline formset:
# forms.py
class AssessmentForm(ModelForm):
class Meta:
model = Assessment
exclude = ('category',)
CategoryAssessmentFormSet = inlineformset_factory(
Assessment,
Assessment.category.through,
fields=['category', 'value'],
can_delete=False,
extra=Category.objects.count(),
max_num=Category.objects.count(),
widgets={'category': Select(attrs={'hidden': 'true'})}
)
in my view, to render the formset:
# views.py
initial = [{'category': category} for category in Category.objects.all()]
formset = CategoryAssessmentFormSet(initial=initial)
Select is hidden but I still want the name of the selected field, in my template:
# template
{{ formset.management_form }}
{% for form in formset %}
<div class="p-2">
{% for value,selected in form.fields.category.choices %}
{% if value == form.category.value %}{{ selected }}{% endif %}
{% endfor %}
{{ form.category }}
</div>
<div>
{{ form.value}}
</div>
{% endfor %}

django specific user content/data

I'm trying to display specific content/data based on a logged in user. I want to display only their info. This is what I've tried but I can't get it to work.
views.py
class DemoView(TemplateView):
template_name = 'demographics/demographics.html'
def get(self, request):
demos = Demographics.objects.filter(user=request.user)
context = {
'demos': demos,
}
return render(request, self.template_name, context)
models.py
class Demographics(models.Model):
first_name = models.CharField(max_length=50, null=True)
middle_name = models.CharField(max_length=50, null=True)
last_name = models.CharField(max_length=50, null=True)
user = models.ForeignKey(User, null=True)
HTML
{% if demos %}
{% for demographics in demos %}
<p>First Name</p> {{ demographics.first_name }}
{% endfor %}
{% else %}
<h3>you dont have demo yet</h3>
{% endif %}
I feel like I'm close. What am I missing?

I think the issue may be that you are filtering out all answers from your queryset because the content of request.user is not quite a match for a 'user' object. I don't know why they wouldn't match, but in my code I use:
User.objects.get(username = request.user.username)

I think debugging using pdb will help why the get is not rendering the data properly but if you know how django templateview class handles the context data, you have to modify the code a bit. Here I used get_context_data instead of get and hope this time it will work.
class DemoView(TemplateView):
template_name = 'demographics/demographics.html'
def get_context_data(self, **kwargs):
context = super(DemoView, self).get_context_data(**kwargs)
demos = Demographics.objects.filter(user=self.request.user)
context['demos'] = demos
return context
Also you can check if the table Demographics has the data for the selected user.

full Answer:
Views.py
class DemoView(TemplateView):
template_name = 'demographics/demographics.html'
def get(self, request, *args, **kwargs):
demos = Demographics.objects.filter(user=User.objects.get (username=request.user))
context = {
'demos': demos,
}
return render(request, self.template_name, context)
HTML:
{% if demos %}
{% for demographics in demos %}
<p>First Name</p> {{ demographics.first_name }}
{% endfor %}
{% else %}
<h3>you dont have demo yet</h3>
{% endif %}
urls.py
url(r'^test/', views.DemoView.as_view()),
admin.py
admin.site.register(Demographics)
models.py
class Demographics(models.Model):
first_name = models.CharField(max_length=50, null=True)
middle_name = models.CharField(max_length=50, null=True)
last_name = models.CharField(max_length=50, null=True)
user = models.ForeignKey(User, null=True)
Go to django admin, check your objects, and make sure you're logged in to the account that has demographic objects associated with it.
The above setup works for me, if it doesn't work for you, you're most likely logged in as a user which doesn't have any demographic objects associated with it.
Also, don't name your models as plural, it should be Demographic, because it is a representation of one object. When you filter in views, you name the variable demographics (plural), because the query returns more than one object.

Bringing Information from django.contrib.auth.models.User into View

I have the following model in my Django project:
from django.contrib.auth.models import User
class Project(models.Model):
project_title = models.CharField(max_length=200)
project_description = models.CharField(max_length=200, default="")
created_date = models.DateTimeField('date created')
owner = models.ForeignKey(User)
def __str__(self):
return self.project_title
This view uses the Project model as follows:
class ProjectView(generic.edit.UpdateView):
model = Project
fields = ['project_title','project_description']
template_name = 'steps/project.html'
success_url = reverse_lazy('steps:index')
My question is how can I bring the User's fields into my ProjectView so I can then use them in templates? In particular, I would like to display the logged-in user's name and email.

user information placed on request, not on views. So you can write in template {{user.username}}, or {{user.email}}. and you'll get it. Of course if user.is_authenticated

in your template write:
{% if request.user.is_authenticated %}
{{ request.user.username }}
{{ request.user.email }}
{% endif %}