Django-Rest-Framework 权限管理源码浅析(小结)

# 方式1: 装饰器
from rest_framework.decorators import api_view, authentication_classes, permission_classes
from rest_framework.authentication import SessionAuthentication, BasicAuthentication
from rest_framework.permissions import AllowAny
from rest_framework.response import Response


@api_view(["GET", ])
@permission_classes([AllowAny,])
@authentication_classes([SessionAuthentication, BasicAuthentication])
def test_example(request):
 content = {
   'user': unicode(request.user), # `django.contrib.auth.User` instance.
   'auth': unicode(request.auth), # None
  }
  return Response(content)

# ------------------------------------------------------------
# 方式2: 类
from rest_framework.authentication import SessionAuthentication, BasicAuthentication
from rest_framework.permissions import AllowAny
from rest_framework.response import Response
from rest_framework.views import APIView

class ExampleView(APIView):
 authentication_classes = (SessionAuthentication, BasicAuthentication)
 permission_classes = (AllowAny,)

 def get(self, request, format=None):
  content = {
   'user': unicode(request.user), # `django.contrib.auth.User` instance.
   'auth': unicode(request.auth), # None
  }
  return Response(content)

REST_FRAMEWORK = {
 ...
 'DEFAULT_AUTHENTICATION_CLASSES': (
  'your_authentication_class_path',
 ),
 ...
}

api_settings = APISettings(None, DEFAULTS, IMPORT_STRINGS)

@property
def user_settings(self):
 if not hasattr(self, '_user_settings'):
  # _user_settings默认为加载项目settings文件中的REST_FRAMEWORK对象
  self._user_settings = getattr(settings, 'REST_FRAMEWORK', {})
 return self._user_settings

def __getattr__(self, attr):
 if attr not in self.defaults:
  raise AttributeError("Invalid API setting: '%s'" % attr)

 try:
  # Check if present in user settings
  # 优先加载user_settings，即项目的settings文件，没有就用默认
  val = self.user_settings[attr]
 except KeyError:
  # Fall back to defaults
  val = self.defaults[attr]

 # Coerce import strings into classes
 if attr in self.import_strings:
  val = perform_import(val, attr)

 # Cache the result
 self._cached_attrs.add(attr)
 setattr(self, attr, val)
 return val

# views.py
from rest_framework.views import APIView
from rest_framework.permissions import IsAuthenticated


class ExampleAPIView(APIView):
 permission_classes = (IsAuthenticated,)
 ...
 
# -----------------------------
from django.conf.urls import url, include

from .views import ExampleAPIView

urlpatterns = [
 url(r'^example/(?P<example_id>[-\w]+)/examples/?$',
  ExampleAPIView.as_view()),
]

def get_authenticators(self):
  """
  Instantiates and returns the list of authenticators that this view can use.
  """
  return [auth() for auth in self.authentication_classes]

class IsAuthenticatedOrReadOnly(BasePermission):
 """
 The request is authenticated as a user, or is a read-only request.
 """

 def has_permission(self, request, view):
  return (
   request.method in SAFE_METHODS or
   request.user and
   request.user.is_authenticated
  )