Added history_user middleware

Author: macro1

docs/usage.rst

@@ -46,6 +46,21 @@ Django tutorial:
 Now all changes to ``Poll`` and ``Choice`` model instances will be tracked in
 the database.
 
+The historical models can also track who made each change. To populate
+the history user automatically you can add middleware to your Django
+settings:
+
+.. code-block:: python
+
+    MIDDLEWARE_CLASSES = [
+        # ...
+        'simple_history.middleware.HistoryRequestMiddleware',
+    ]
+
+If you do not want to use the middleware, you can explicitly indicate
+the user making the change as indicated in the advanced usage
+documentation.
+
 .. _admin_integration:
 
 Integration with Django Admin

runtests.py

@@ -37,6 +37,7 @@
         'django.contrib.sessions.middleware.SessionMiddleware',
         'django.contrib.auth.middleware.AuthenticationMiddleware',
         'django.contrib.messages.middleware.MessageMiddleware',
+        'simple_history.middleware.HistoryRequestMiddleware',
     ],
 )
 

simple_history/middleware.py

@@ -0,0 +1,11 @@
+from . models import HistoricalRecords
+
+
+class HistoryRequestMiddleware(object):
+    """Expose the request as a thread-friendly variable on the
+    HistoricalRecords class.
+
+    """
+
+    def process_request(self, request):
+        HistoricalRecords.thread.request = request

simple_history/models.py

@@ -1,5 +1,6 @@
 from __future__ import unicode_literals
 
+import threading
 import copy
 try:
     from django.apps import apps  # Django >= 1.7
@@ -53,6 +54,8 @@ def python_2_unicode_compatible(klass):
 
 
 class HistoricalRecords(object):
+    thread = threading.local()
+
     def __init__(self, verbose_name=None, bases=(models.Model,)):
         self.user_set_verbose_name = verbose_name
         try:
@@ -213,14 +216,27 @@ def post_delete(self, instance, **kwargs):
 
     def create_historical_record(self, instance, type):
         history_date = getattr(instance, '_history_date', now())
-        history_user = getattr(instance, '_history_user', None)
+        history_user = self.get_history_user(instance)
         manager = getattr(instance, self.manager_name)
         attrs = {}
         for field in instance._meta.fields:
             attrs[field.attname] = getattr(instance, field.attname)
         manager.create(history_date=history_date, history_type=type,
                        history_user=history_user, **attrs)
 
+    def get_history_user(self, instance):
+        """Use hints from the instance and middleware to identify the
+        user making the change.
+
+        """
+        try:
+            return instance._history_user
+        except AttributeError:
+            try:
+                return self.thread.request.user
+            except AttributeError:
+                return
+
 
 class ForeignKeyMixin(object):
     def get_attname(self):

simple_history/tests/tests/test_admin.py

@@ -114,7 +114,7 @@ def test_history_form(self):
         self.assertEqual(poll.question, "what?")
         self.assertEqual(poll.pub_date, tomorrow)
         self.assertEqual([p.history_user for p in Poll.history.all()],
-                         [self.user, None, None])
+                         [self.user] * 3)
 
     def test_history_user_on_save_in_admin(self):
         self.login()