import enum
import warnings
from aiohttp import web
from aiohttp_security.abc import (AbstractIdentityPolicy,
AbstractAuthorizationPolicy)
from functools import wraps
IDENTITY_KEY = 'aiohttp_security_identity_policy'
AUTZ_KEY = 'aiohttp_security_autz_policy'
async def remember(request, response, identity, **kwargs):
"""Remember identity into response.
The action is performed by identity_policy.remember()
Usually the identity is stored in user cookies somehow but may be
pushed into custom header also.
"""
assert isinstance(identity, str), identity
assert identity
identity_policy = request.config_dict.get(IDENTITY_KEY)
if identity_policy is None:
text = ("Security subsystem is not initialized, "
"call aiohttp_security.setup(...) first")
# in order to see meaningful exception message both: on console
# output and rendered page we add same message to *reason* and
# *text* arguments.
raise web.HTTPInternalServerError(reason=text, text=text)
await identity_policy.remember(request, response, identity, **kwargs)
async def forget(request, response):
"""Forget previously remembered identity.
Usually it clears cookie or server-side storage to forget user
session.
"""
identity_policy = request.config_dict.get(IDENTITY_KEY)
if identity_policy is None:
text = ("Security subsystem is not initialized, "
"call aiohttp_security.setup(...) first")
# in order to see meaningful exception message both: on console
# output and rendered page we add same message to *reason* and
# *text* arguments.
raise web.HTTPInternalServerError(reason=text, text=text)
await identity_policy.forget(request, response)
async def authorized_userid(request):
identity_policy = request.config_dict.get(IDENTITY_KEY)
autz_policy = request.config_dict.get(AUTZ_KEY)
if identity_policy is None or autz_policy is None:
return None
identity = await identity_policy.identify(request)
if identity is None:
return None # non-registered user has None user_id
user_id = await autz_policy.authorized_userid(identity)
return user_id
async def permits(request, permission, context=None):
assert isinstance(permission, (str, enum.Enum)), permission
assert permission
identity_policy = request.config_dict.get(IDENTITY_KEY)
autz_policy = request.config_dict.get(AUTZ_KEY)
if identity_policy is None or autz_policy is None:
return True
identity = await identity_policy.identify(request)
# non-registered user still may has some permissions
access = await autz_policy.permits(identity, permission, context)
return access
async def is_anonymous(request):
"""Check if user is anonymous.
User is considered anonymous if there is not identity
in request.
"""
identity_policy = request.config_dict.get(IDENTITY_KEY)
if identity_policy is None:
return True
identity = await identity_policy.identify(request)
if identity is None:
return True
return False
async def check_authorized(request):
"""Checker that raises HTTPUnauthorized for anonymous users.
"""
userid = await authorized_userid(request)
if userid is None:
raise web.HTTPUnauthorized()
return userid
def login_required(fn):
"""Decorator that restrict access only for authorized users.
User is considered authorized if authorized_userid
returns some value.
"""
@wraps(fn)
async def wrapped(*args, **kwargs):
request = args[-1]
if not isinstance(request, web.BaseRequest):
msg = ("Incorrect decorator usage. "
"Expecting `def handler(request)` "
"or `def handler(self, request)`.")
raise RuntimeError(msg)
await check_authorized(request)
return await fn(*args, **kwargs)
warnings.warn("login_required decorator is deprecated, "
"use check_authorized instead",
DeprecationWarning)
return wrapped
async def check_permission(request, permission, context=None):
"""Checker that passes only to authoraised users with given permission.
If user is not authorized - raises HTTPUnauthorized,
if user is authorized and does not have permission -
raises HTTPForbidden.
"""
await check_authorized(request)
allowed = await permits(request, permission, context)
if not allowed:
raise web.HTTPForbidden()
def has_permission(
permission,
context=None,
):
"""Decorator that restricts access only for authorized users
with correct permissions.
If user is not authorized - raises HTTPUnauthorized,
if user is authorized and does not have permission -
raises HTTPForbidden.
"""
def wrapper(fn):
@wraps(fn)
async def wrapped(*args, **kwargs):
request = args[-1]
if not isinstance(request, web.BaseRequest):
msg = ("Incorrect decorator usage. "
"Expecting `def handler(request)` "
"or `def handler(self, request)`.")
raise RuntimeError(msg)
await check_permission(request, permission, context)
return await fn(*args, **kwargs)
return wrapped
warnings.warn("has_permission decorator is deprecated, "
"use check_permission instead",
DeprecationWarning)
return wrapper
def setup(app, identity_policy, autz_policy):
assert isinstance(identity_policy, AbstractIdentityPolicy), identity_policy
assert isinstance(autz_policy, AbstractAuthorizationPolicy), autz_policy
app[IDENTITY_KEY] = identity_policy
app[AUTZ_KEY] = autz_policy
|