Question

This is my login view:

def sign_in(request):
    if request.method == 'POST':
        form = LoginForm(request.POST)
        if form.is_valid():
            username = request.POST['username']
            password = request.POST['password']
            user = authenticate(username=username, password=password)
            if user is not None:
                if user.is_active:
                    login(request, user)
                    redirect('/')
                else:
                    # Return a 'disabled account' error message
                    return render_to_response('message.html', {...})
            else:
                # Return an 'invalid login' error message.
                ???

    else:
        form = LoginForm()

    return render(request, 'accounts/login.html', {
        'form': form,
        })

And this is my LoginForm class:

class LoginForm(forms.Form):
    username = forms.CharField(required=True, max_length=30)
    password = forms.CharField(required=True, widget=forms.PasswordInput(), max_length=128)

The missing part is # Return an 'invalid login' error message.
???

How can I redisplay the form with the error message saying invalid login?

Answer 1

To show form errors you should use {{ form.name_of_field.errors }} and {{ form.non_field_errors }}. In your case you can:

    ...
    else:
        # Return an 'invalid login' error message.
        message = 'Your message'

return render(request, 'accounts/login.html', {
    'form': form, 'message': message
    })

You can also remove unnecessary if request.method == 'POST': using: form = LoginForm(request.POST or None)