Validation errors don't show in Django form - django

Question

When I try to test my form with an email which has already been entered into the database it doesn't give the error message like it should, it redirects back to the homepage.
My views.py file looks like this:
from django.shortcuts import render
from .forms import LotteryForm
from django.http import HttpResponseRedirect
# Create your views here.
def lottery_list(request):
return render(request, 'lottery/lottery.html', {})
def lottery_new(request):
if request.method == 'POST':
form = LotteryForm(request.POST)
if form.is_valid():
form.save()
return HttpResponseRedirect('lottery_submitted')
else:
return render(request, 'lottery/lottery.html' {'form': LotteryForm()})
else:
form = LotteryForm()
return render(request, 'lottery/lottery.html', {'form': LotteryForm()})
My form is:
from django import forms
from django.db import models
from django.forms import ModelForm
from .models import Lottery
from .models import Lottery_user
from django.core.exceptions import ValidationError
class LotteryForm(forms.ModelForm):
lottery_type = forms.ModelChoiceField(queryset = Lottery.objects.all(), empty_label=None)
first_name = forms.CharField(required=True)
last_name = forms.CharField(required=True)
lottery_numbers = forms.CharField(max_length=12, required=True)
email = forms.EmailField(required=True)
telephone = forms.CharField(max_length=18,
error_messages={'invalid':'Enter a valid mobile number',
'required':'Enter a valid mobile number'})
def clean_email(self):
email = self.cleaned_data['email']
if Lottery_user.objects.filter(email=email).exists():
raise ValidationError("Email already exists")
return email
if Lottery_user.objects.filter(email=self.cleaned_data['email']).exists():
raise ValidationError("You've already entered")
return email
class Meta:
model = Lottery_user
fields = ['lottery_numbers', 'lottery_type', 'first_name', 'last_name', 'email', 'telephone',]
Template form:
<form action="{% url 'lottery_new' %}" method="post">
{% csrf_token %}
<div class="fieldWrapper">
<label for="lotterytype">Choose a lottery:</label>
{{ form.lottery_type }}
<p>See <a href=lottery_instructions>instructions and rules</a></p>
</div>
<div class="fieldWrapper">
<label for="lotterynumbers">Lottery Numbers:</label>
{{ form.lottery_numbers }}
</div>
<div class="fieldWrapper">
<label for="firstname">First name:</label>
{{ form.first_name }}
</div>
<div class="fieldWrapper">
<label for="lastname">Last name:</label>
{{ form.last_name }}
</div>
<div class="fieldWrapper">
{{ form.email.errors }}
{{ form.email.non_field_errors }}
<label for="email">Email:</label>
{{ form.email }}
</div>
<div class="fieldWrapper">
<label for="phonenumber">Telephone Number:</label>
{{ form.telephone }}
</div>
<button type="submit" class="btn btn-default">Submit</button>
</form>
I want a user to not be able to enter twice with the same email, so it should error when the user clicks submit with a used email address.
Also, does anyone know how to get the error messages to show before the user submits rather than afterwards?

Answer 1

You return a newly instantiated form when the form is invalid, when you should instead return the invalid form (with the errors). Try:
def lottery_new(request):
if request.method == 'POST':
form = LotteryForm(request.POST)
if form.is_valid():
....
else:
return render(request, 'lottery/lottery.html' {'form': form})