Tukukkk

I want to show a validation message like "This email is already in use" inside my html form.

But I think i'm missing something. I keep getting an IntegrityError at my email field. Isn't Django supposed to validate this and give an ValidationError if I use unique=True in my model? Or do I have to Try and Catch the IntegrityError myself?

Or maybe show me a best practice for validating unique users inside a form/model.

models.py

class Customer(models.Model):

    FirstName = models.CharField(max_length=50)

    LastName = models.CharField(max_length=50)

    Email = models.CharField(max_length=50, unique=True, error_messages={'unique':"This email is already in use"})

views.py

def customerform(request):

if request.method == 'POST':

    form = CustomerForm(request.POST)

    if form.is_valid():

        post = Customer()

        post.FirstName = form.cleaned_data['FirstName']

        post.LastName = form.cleaned_data['LastName']

        post.Email = form.cleaned_data['Email']

        post.save()

        return render(request, 'results.html', {

        'FirstName': form.cleaned_data['FirstName'],

        'Email': form.cleaned_data['Email'],})

else:        

    form = CustomerForm()

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

forms.py

class CustomerForm(forms.Form):

    FirstName   = forms.CharField (label='First name:', max_length=50)

    LastName    = forms.CharField (label='Last name:', max_length=50)

    Email       = forms.EmailField(label='Email:', max_length=50)

form.html

<form action="/customer/" method="post">

    {% csrf_token %}

    {{ form }}

    <input type="submit" value="Submit">

</form>

If you want form validation to automatically use the model attributes, you have to use a ModelForm:

class CustomerForm(forms.ModelForm):

    class Meta:

        model = Customer

        fields = ["FirstName", "LastName", "Email"]

If you want to use a regular Form, you need to do the validation manually.

def customerform(request):

    if request.method == 'POST':

        form = CustomerForm(request.POST)

        if form.is_valid():

            # first we check if email is valid

            customer = Customer.objects.filter(Email = form.cleaned_data['Email'])

            if customer.count() == 0: # email not in use

                post = Customer()

                post.FirstName = form.cleaned_data['FirstName']

                post.LastName = form.cleaned_data['LastName']

                post.Email = form.cleaned_data['Email']

                post.save()

                return render(request, 'results.html', {

                    'FirstName': form.cleaned_data['FirstName'],

                     'Email': form.cleaned_data['Email'],})

            else: # email in use so we redirect to html and we add an error message

                render(request, 'form.html', {'form':form,'error','This email is already in use'})

        else:        

            form = CustomerForm()

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





<form action="/customer/" method="post">

    {% if error %}

        <b> {{ error }} </b> <br>

    {% endif %}

    {% csrf_token %}

    {{ form }}

    <input type="submit" value="Submit">

</form>