👀 Views: 100 💬 Answers: 1 📅 Created: 2025-10-05

django forms validation Python

I'm experimenting with I've been banging my head against this for hours. Currently developing a portfolio project using Django 3.2, and I've run into a snag with form validation. I created a custom form where one of the fields needs to check the uniqueness of user input against a model instance. However, the validation doesn't seem to trigger as expected, and I'm not getting the feedback I need when the input is invalid. The form looks something like this: ```python from django import forms from .models import UserProfile class UserProfileForm(forms.ModelForm): class Meta: model = UserProfile fields = ['username', 'email'] def clean_username(self): username = self.cleaned_data.get('username') if UserProfile.objects.filter(username=username).exists(): raise forms.ValidationError('Username is already taken.') return username ``` In my view, I handle the form submission like this: ```python from django.shortcuts import render, redirect from .forms import UserProfileForm def create_profile(request): if request.method == 'POST': form = UserProfileForm(request.POST) if form.is_valid(): form.save() return redirect('profile_success') else: form = UserProfileForm() return render(request, 'create_profile.html', {'form': form}) ``` When testing this, I noticed that if I enter a username that already exists, the form still submits without showing the validation error. I've tried adding print statements to debug the flow, and everything seems to be processing correctly up to the point of validation. Could there be an issue with how Django is handling form validation in this context? Are there any common pitfalls I might be missing? I've read through the documentation a few times and couldn’t find anything that I overlooked. Any tips or suggestions to fix this would be greatly appreciated! This issue appeared after updating to Python latest. How would you solve this?