Can not add values from forms to Django models - django

Question

I made a form and there I had a multiple-choice field called artists which I got from my database and while adding a song a user can select multiple artists and save the song.
The artists are a ManyToManyField in Django models.
models.py
class Artists(models.Model):
""" Fields for storing Artists Data """
artist_name = models.CharField(max_length = 50, blank = False)
dob = models.DateField()
bio = models.TextField(max_length = 150)
def __str__(self):
return self.artist_name
class Songs(models.Model):
""" Fields for storing song data """
song_name = models.CharField(max_length = 30, blank = False)
genre = models.CharField(max_length = 30, blank = False)
artist = models.ManyToManyField(Artists)
release_date = models.DateField()
forms.py
class Song_input(forms.Form):
queryset = Artists.objects.only('artist_name')
OPTIONS = []
for i in queryset:
s = []
s = [i, i]
OPTIONS.append(s)
artist_name = forms.MultipleChoiceField(widget=forms.CheckboxSelectMultiple,choices=OPTIONS)
song_name = forms.CharField()
genre = forms.CharField()
release_date = forms.DateField(widget=DateInput)
Now I want to get all the values selected from the form and save to my database. Here the artist_name may have multiple values.
I have tried using the add() and create() methods but can not figure out how to add all the data where one field (artist_name) having multiple data to my database.

Answer 1

I strongly advise to make use of a ModelForm [Django-doc]. Especially since you make use of ManyToManyFields, which are more cumbersome to save yourself.
# app/forms.py
from django import forms
class SongForm(forms.ModelForm):
class Meta:
model = Songs
fields = '__all__'
widgets = {
'artist': forms.CheckboxSelectMultiple,
'release_date': forms.DateInput
}
There is thus no need to specify the fields yourself, you can change the widgets by adding these to the widgets dictionary [Django-doc] of the Meta subclass.
In your view, you can then both render and sae objects with that form:
# app/views.py
from app.forms import SongForm
def add_song(request):
if request.method == 'POST':
form = SongForm(request.POST, request.FILES)
if form.is_valid():
form.save()
return redirect('name-of-some-view')
else:
form = SongForm()
return render(request, 'some-template.html', {'form': form})
The form.save() will save the object in the database.
In the template, you can then render the template:
<form method="post" action="{% url 'name-of-add_song-view' %}">
{% csrf_token %}
{{ form }}
<input type="submit" value="Submit">
</form>