Django Forms custom error message in views - django

Question

This is my view:
if request.method == 'POST':
form = TeacherRegister(request.POST)
#Gets school object from email domain.
email = form['email'].value().split('#')[1]
try:
school = School.objects.get(email_domain = email)
except ObjectDoesNotExist:
#add custom error message here
if form.is_valid():
user, Teacher = form.save()
Teacher.school = school
Teacher.save()
user.groups.add(Group.objects.get(name='Teacher'))
#user.is_active to stop users logging in without confirming their emails
user.is_active = False
user.save()
#Sends confirmation link.
send_confirmation_email(request, user)
args = {'email': user.email,
'link': user.Teacher.school.email_website}
return render(request, 'email/token_sent.html', args)
else:
args = {'form': form,}
return render(request, 'users/teachers.html', args)
These lines are what I am trying to work with:
email = form['email'].value().split('#')[1]
try:
school = School.objects.get(email_domain = email)
except ObjectDoesNotExist:
#add custom error message here
This is the HTML I have for the email field:
<div class="required field" >
{{ form.email.label }}
{{ form.email }}
{{ form.email.help_text }}
<!-- <label>Email</label>
<input placeholder="Email" type="email" name="email" autofocus="" required="" id="id_email"> -->
</div>
How can I get it to say, if no school object is returned, something along the lines of 'School not found, check your email'?
Thanks

Answer 1

You need to perform validation on the form side.
Implement clean_email method in the form:
def clean_email(self):
email = self.cleaned_data.get('email')
email = email.split('#')[1]
try:
school = School.objects.get(email_domain = email)
except ObjectDoesNotExist:
raise forms.ValidationError(''School not found, check your email')
return email
Now in template you can show this error right after email field:
{{ form.email.label }}
{{ form.email }}
{{ form.email.errrors }}
{{ form.email.help_text }}

Answer 2

You can try Django's built-in messages framework. Try this:
try:
school = School.objects.get(email_domain = email)
except ObjectDoesNotExist:
messages.error(request, 'School not found, check your email')
And then somewhere above your form, add this:
{% if messages %}
{% for message in messages %}
<div class="alert {% if message.tags %} alert-{{ message.tags }}{% endif %}">{{ message|safe }}</div>
{% endfor %}
{% endif %}
Hope it helps!