django1/django/contrib/formtools/utils.py

29 lines
891 B
Python

from __future__ import unicode_literals
# Do not try cPickle here (see #18340)
import pickle
from django.utils.crypto import salted_hmac
from django.utils import six
def form_hmac(form):
"""
Calculates a security hash for the given Form instance.
"""
data = []
for bf in form:
# Get the value from the form data. If the form allows empty or hasn't
# changed then don't call clean() to avoid trigger validation errors.
if form.empty_permitted and not form.has_changed():
value = bf.data or ''
else:
value = bf.field.clean(bf.data) or ''
if isinstance(value, six.string_types):
value = value.strip()
data.append((bf.name, value))
pickled = pickle.dumps(data, pickle.HIGHEST_PROTOCOL)
key_salt = 'django.contrib.formtools'
return salted_hmac(key_salt, pickled).hexdigest()