Unable to add comments to a post using a ModelForm in Django

Question

views.py

def postdetail(request,pk): # Single Post view.

    post = Post.objects.get(id=pk)
    comment = post.comments.all()
    comment_count = comment.count()

    if request.user.is_authenticated:

        if request.method == 'POST':
            form = CommentForm(data=request.POST)
            content = request.POST['cMessage']

            if form.is_valid():
                print("Yes valid")
                form.instance.body = content
                new_comment = form.save(commit=False)
                print(new_comment)
                new_comment.post = post
                new_comment.user = request.user
                new_comment.save()
                return redirect('blog-home')
        else:

            form = CommentForm()

    context = {
        'comment_form': CommentForm,
        'post' : post,
        'comments': comment,
        'count': comment_count,
    }

    return render(request,'post/postdetail.html', context=context)

models.py

class Comment(models.Model):

    post = models.ForeignKey(Post, on_delete=models.CASCADE, related_name='comments')
    user = models.ForeignKey(User,on_delete=models.CASCADE, related_name='comments')
    body = models.TextField()
    created = models.DateTimeField(auto_now_add=True)
    updated = models.DateTimeField(auto_now=True)
    # active = models.BooleanField(default=True)

    class Meta:
        ordering = ('created',)

    def __str__(self):
        return f'Comment by {self.user} on {self.post}'

forms.py

class CommentForm(forms.ModelForm):
    class Meta:
        model = Comment
        fields = ['body']

template

{% if request.user.is_authenticated %}
    <!-- respond -->
    <div class="respond">
        <h3>Leave a Comment</h3>
            <!-- form -->
                <form name="contactForm" id="contactForm" method="post" action="">
                {% csrf_token %}
                <fieldset>

                    <div class="message group">
                        <label  for="cMessage">Message <span class="required">*</span></label>
                        <textarea name="cMessage"  id="cMessage" rows="10" cols="50" ></textarea>
                    </div>

                    <button type="submit" class="submit">Submit</button>

                </fieldset>
                </form> <!-- Form End -->
    </div> 
{% endif %}

There is no error being displayed neither If I am adding a comment using the shell/through admin panel but if I am trying to add the comment dynamically through the form then the comment is not getting saved. I have added only the form in the template.

Answer 1

In views.py

def postdetail(request):
    print(Comment.objects.all())

    if request.method == 'POST':
            form = CommentForm(data=request.POST)
            content = request.POST['body']

            if form.is_valid():
                print("Yes valid")
                new_comment = form.save(commit=False)
                print(new_comment)
                new_comment.post = post
                new_comment.user = request.user
                new_comment.save()
                return redirect('blog-home')
        else:
            form = CommentForm()
    return render(request,'temp/postdetail.html', context=context)

In html file

{% if request.user.is_authenticated %}
    <div class="respond">
        <h3>Leave a Comment</h3>
        <form name="contactForm" id="contactForm" method="post" action="">
            {% csrf_token %}
            <textarea name="body"cols="30" rows="10"></textarea>
            <button type="submit" class="submit">Submit</button>
        </form>
    </div>
{% endif %}

This worked for me.

Answer 2

You have defined field body in your CommentForm. It's required in your form, because you didn't include blank=True argument in your model for this field. This means that when you POST request and check if form is valid with form.is_valid(), the form expects an element with a name body in the request. If it's not there, it will not validate and content won't be saved.

Make the following changes:

1. Change your view to

   ...
   if request.method == 'POST':
       form = CommentForm(data=request.POST)
       if form.is_valid():
           new_comment = form.save(commit=False)
           new_comment.post = post
           new_comment.user = request.user
           new_comment.save()
           return redirect('blog-home')
       else:
           print(form.errors) # or log it to a file, if you have logging set up
   
   form = CommentForm()
   ...
   

2. Change your HTML to this:

   ...
   <form name="contactForm" id="contactForm" method="post" action="">
       {% csrf_token %}
       <fieldset>
           <div class="message group">
               <label  for="body">Message <span class="required">*</span></label>
               <textarea name="body" id="cMessage" rows="10" cols="50" ></textarea>
               {{ comment_form.body.errors }}
           </div>
           <button type="submit" class="submit">Submit</button>
       </fieldset>
   </form>
   ...