foreign key in django - django

Question

I have a model for musics and a model for comment of musics:
class music(models.Model):
author = models.ForeignKey(User, on_delete=models.CASCADE)
STATUS_CHOICES = (('draft', 'Draft'), ('published', 'Published'),)
music = models.FileField()
music_image = models.ImageField(upload_to="images/")
singer_name = models.CharField(max_length=100)
music_name = models.CharField(max_length=100)
text_of_music = models.TextField()
create = models.DateField(auto_now_add=True, blank=True, null=True)
update = models.DateField(auto_now=True, blank=True, null=True)
publish = models.DateField(default=timezone.now, blank=True, null=True)
slug = models.CharField(max_length=250, unique_for_date='publish')
status = models.CharField(max_length=10, choices=STATUS_CHOICES, default='draft')
objects = models.Manager()
published = PublishedManager()
class Meta:
ordering = ('-publish',)
def get_absolute_url(self):
return reverse('music:music_detail',
kwargs={"id":self.id})
class comment(models.Model):
# Foreignkey for each music
For = models.ForeignKey(music, on_delete=models.CASCADE, related_name='post')
body = models.CharField(max_length=500)
created_on = models.DateTimeField(auto_now_add=True)
active = models.BooleanField(default=True)
commented_by = models.ForeignKey(User, on_delete=models.CASCADE)
and this is my view:
def music_Detail(request, id=None):
user = request.user
template_name = 'music/music_detail.html'
Music = music.objects.all().filter(id=id)
new_comment = None
Comment = comment.objects.all().filter(active=True)
form = comment_form(data=request.POST)
if request.method == 'POST':
if form.is_valid():
new_comment = form.save(commit=False)
new_comment.For = Music
new_comment.save()
form = comment_form()
return render(request, template_name, {'Music': Music, 'Comment': Comment, 'form': form})
Well, I get this error when I comment:
Cannot assign "<QuerySet [<music: m, majid kharatha>]>": "comment.For" must be a "music" instance.
How can I solve this problem and how can I display the information of the user who left this comment?

Answer 1

As the error says, you'll have to assign a single Music, not a queryset.
Instead of filter()ing to get a new queryset containing a single music,
Music = music.objects.all().filter(id=id)
you want to get() a single one:
Music = music.objects.get(id=id)