Django derive model field based on other field value - django

Question

I have a CustomUser model
class Account(AbstractBaseUser):
email = models.EmailField(verbose_name = "email", max_length = 60, unique = True)
username = models.CharField(max_length = 30, unique = True)
I am using a User creation form to register new users as follows,
class RegistrationForm(UserCreationForm):
email = forms.EmailField(max_length = 60, help_text = "This will be your login.")
class Meta:
model = Account
fields = ("email", "username", "password1", "password2")
What I want to do is remove the "username" from the form fields, so
fields = ("email", "password1", "password2")
And then when the user submits the form, I wish to insert a value into the username field based on the email provided by the user, for e.g. email = abc#xyz.com, then username = abc.
How do I do this?

Answer 1

form.py
class UserCreateForm(UserCreationForm):
password1 = forms.CharField(widget=forms.PasswordInput(attrs={'class':'form-control'}))
password2 = forms.CharField(widget=forms.PasswordInput(attrs={'class':'form-control'}))
class Meta:
model = User
fields = ['email','first_name','last_name','password1','password2']
exclude = ['username']
widgets = {
'username':forms.TextInput(attrs={'class':'form-control'}),
# 'first_name':forms.TextInput(attrs={'class':'form-control'}),
# 'last_name':forms.TextInput(attrs={'class':'form-control'}),
'email':forms.EmailInput(attrs={'class':'form-control'}),
}
view.py
def RegisterView(request):
if request.method == 'POST':
form = UserCreateForm(request.POST)
if form.is_valid():
email = form.cleaned_data['email']
fm = form.save(commit=False)
fm.username = email.split("#")[0]
fm.save()
messages.success(request,f'{email} Successfully Registred')
form = UserCreateForm()
return render(request, 'index.html', {'form': form})
else:
form = UserCreateForm()
context = {'form': form, }
return render(request, 'index.html', context)
HTML Code
<form action="" method="post">
{% csrf_token %}
{% for i in form %}
<p>{{i.label}} {{i}}</p>
{% endfor %}
<button type="submit">Add</button>
</form>
Webpage output (register form)
admin panel