From a62a2178d02d9a7c6c8582e7b6cf34591107d784 Mon Sep 17 00:00:00 2001
From: ibuler <ibuler@qq.com>
Date: Sat, 15 Oct 2016 00:49:59 +0800
Subject: [PATCH] Add user backend

---
 apps/common/utils.py   | 26 +++++++++++++++++++----
 apps/users/backends.py | 47 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 69 insertions(+), 4 deletions(-)
 create mode 100644 apps/users/backends.py

diff --git a/apps/common/utils.py b/apps/common/utils.py
index ecbb293d6..a5af4f66c 100644
--- a/apps/common/utils.py
+++ b/apps/common/utils.py
@@ -7,15 +7,19 @@ from itertools import chain
 import string
 import logging
 
-from itsdangerous import TimedJSONWebSignatureSerializer
+from itsdangerous import Signer, TimedJSONWebSignatureSerializer, JSONWebSignatureSerializer, TimestampSigner, \
+    BadSignature, SignatureExpired
 from django.shortcuts import reverse as dj_reverse
 from django.conf import settings
 from django.core import signing
 from django.utils import timezone
 
+SECRET_KEY = settings.SECRET_KEY
+SIGNER = TimestampSigner(SECRET_KEY)
 
-def reverse(viewname, urlconf=None, args=None, kwargs=None, current_app=None, external=False):
-    url = dj_reverse(viewname, urlconf=urlconf, args=args, kwargs=kwargs, current_app=current_app)
+
+def reverse(view_name, urlconf=None, args=None, kwargs=None, current_app=None, external=False):
+    url = dj_reverse(view_name, urlconf=urlconf, args=args, kwargs=kwargs, current_app=current_app)
 
     if external:
         url = settings.SITE_URL.strip('/') + url
@@ -44,13 +48,27 @@ def decrypt(*args, **kwargs):
         return ''
 
 
+def sign(value):
+    return SIGNER.sign(value)
+
+
+def unsign(value, max_age=3600):
+    try:
+        return SIGNER.unsign(value, max_age=max_age)
+    except (BadSignature, SignatureExpired):
+        return None
+
+
 def date_expired_default():
     try:
         years = int(settings.CONFIG.DEFAULT_EXPIRED_YEARS)
     except TypeError:
         years = 70
+    return timezone.now() + timezone.timedelta(days=365*years)
+
 
-    return timezone.now() + timezone.timedelta(days=365 * years)
+def sign(value):
+    return SIGNER.sign(value)
 
 
 def combine_seq(s1, s2, callback=None):
diff --git a/apps/users/backends.py b/apps/users/backends.py
new file mode 100644
index 000000000..ac4d67ddd
--- /dev/null
+++ b/apps/users/backends.py
@@ -0,0 +1,47 @@
+# -*- coding: utf-8 -*-
+#
+
+from rest_framework import authentication, exceptions
+from django.utils.translation import ugettext as _
+
+from common.utils import unsign
+from .models import User
+
+
+class APPSignAuthentication(authentication.BaseAuthentication):
+    keyword = 'Sign'
+    model = User
+
+    def authenticate(self, request):
+        auth = authentication.get_authorization_header(request).split()
+
+        if not auth or auth[0].lower() != self.keyword.lower().encode():
+            return None
+
+        if len(auth) == 1:
+            msg = _('Invalid sign header. No credentials provided.')
+            raise exceptions.AuthenticationFailed(msg)
+        elif len(auth) > 2:
+            msg = _('Invalid sign header. Sign string should not contain spaces.')
+            raise exceptions.AuthenticationFailed(msg)
+
+        try:
+            sign = auth[1].decode()
+        except UnicodeError:
+            msg = _('Invalid token header. Sign string should not contain invalid characters.')
+            raise exceptions.AuthenticationFailed(msg)
+
+        return self.authenticate_credentials(sign)
+
+    def authenticate_credentials(self, key):
+        try:
+            token = self.model.objects.select_related('user').get(key=key)
+        except self.model.DoesNotExist:
+            raise exceptions.AuthenticationFailed(_('Invalid token.'))
+
+        if not token.user.is_active:
+            raise exceptions.AuthenticationFailed(_('User inactive or deleted.'))
+
+
+if __name__ == '__main__':
+    pass