from functools import wraps
from django import VERSION as DJANGO_VERSION
from django.contrib.auth.decorators import user_passes_test
from django.conf import settings
from django.contrib.auth import REDIRECT_FIELD_NAME
from django.utils.encoding import force_str
from django.shortcuts import resolve_url
from django.contrib.auth.decorators import login_required as django_login_required
from .helpers import add_query_parameters_to_url
def is_authenticated(user):
if DJANGO_VERSION >= (2, 0, 0):
return user.is_authenticated
else:
return user.is_authenticated()
def is_anonymous(user):
if DJANGO_VERSION >= (2, 0, 0):
return user.is_anonymous
else:
return user.is_anonymous()
def anonymous_required(function=None, redirect_url=None):
"""
Decorator requiring the current user to be anonymous (not logged in).
"""
if not redirect_url:
redirect_url = settings.LOGIN_REDIRECT_URL
actual_decorator = user_passes_test(
is_anonymous,
login_url=redirect_url,
redirect_field_name=None
)
if function:
return actual_decorator(function)
return actual_decorator
def login_required(f, redirect_field_name=REDIRECT_FIELD_NAME, login_url=None):
"""
Decorator that wraps django.contrib.auth.decorators.login_required, but supports extracting Shopify's authentication
query parameters (`shop`, `timestamp`, `signature` and `hmac`) and passing them on to the login URL (instead of just
wrapping them up and encoding them in to the `next` parameter).
This is useful for ensuring that users are automatically logged on when they first access a page through the Shopify
Admin, which passes these parameters with every page request to an embedded app.
"""
@wraps(f)
def wrapper(request, *args, **kwargs):
if is_authenticated(request.user):
return f(request, *args, **kwargs)
# Extract the Shopify-specific authentication parameters from the current request.
shopify_params = {
k: request.GET[k]
for k in ['shop', 'timestamp', 'signature', 'hmac']
if k in request.GET
}
# Get the login URL.
resolved_login_url = force_str(resolve_url(login_url or settings.LOGIN_URL))
# Add the Shopify authentication parameters to the login URL.
updated_login_url = add_query_parameters_to_url(resolved_login_url, shopify_params)
django_login_required_decorator = django_login_required(redirect_field_name=redirect_field_name,
login_url=updated_login_url)
return django_login_required_decorator(f)(request, *args, **kwargs)
return wrapper
