get request data in Django form

Here's the way to get the user in your form when using generic views:

In the view, pass the request.user to the form using get_form_kwargs:

class SampleView(View):
    def get_form_kwargs(self):
        kwargs = super(SampleView, self).get_form_kwargs()
        kwargs['user'] = self.request.user
        return kwargs

In the form you will receive the user with the __init__ function:

class SampleForm(Form):
    def __init__(self, user, *args, **kwargs):
        super(SampleForm, self).__init__(*args, **kwargs)
        self.user = user

As ars and Diarmuid have pointed out, you can pass request.user into your form, and use it in validating the email. Diarmuid's code, however, is wrong. The code should actually read:

from django import forms

class UserForm(forms.Form):
    email_address = forms.EmailField(
        widget=forms.TextInput(
            attrs={
                'class': 'required'
            }
        )
    )

    def __init__(self, *args, **kwargs):
        self.user = kwargs.pop('user', None)
        super(UserForm, self).__init__(*args, **kwargs)

    def clean_email_address(self):
        email = self.cleaned_data.get('email_address')

        if self.user and self.user.email == email:
            return email

        if UserProfile.objects.filter(email=email).count():
            raise forms.ValidationError(
                u'That email address already exists.'
            )

        return email

Then, in your view, you can use it like so:

def someview(request):
    if request.method == 'POST':
        form = UserForm(request.POST, user=request.user)
        if form.is_valid():
            # Do something with the data
            pass
    else:
        form = UserForm(user=request.user)
    # Rest of your view follows

Note that you should pass request.POST as a keyword argument, since your constructor expects 'user' as the first positional argument.

Doing it this way, you need to pass user as a keyword argument. You can either pass request.POST as a positional argument, or a keyword argument (via data=request.POST).