From b7d64f0a80180ecfe8900407fbdf5e4196fa7a2a Mon Sep 17 00:00:00 2001
From: Jon Dufresne <jon.dufresne@gmail.com>
Date: Mon, 13 Apr 2020 11:38:27 -0700
Subject: [PATCH] Make DJANGO_REDIS_IGNORE_EXCEPTIONS more test friendly

Calculate the constants as the class is instantiated instead of import
time. This allows overriding the constant using Django's
override_setting without monkey patching the module.
---
 django_redis/cache.py | 26 ++++++++++++--------------
 tests/test_backend.py | 27 +++++++++------------------
 2 files changed, 21 insertions(+), 32 deletions(-)

diff --git a/django_redis/cache.py b/django_redis/cache.py
index d752fbf7..a595103d 100644
--- a/django_redis/cache.py
+++ b/django_redis/cache.py
@@ -7,19 +7,8 @@
 
 from .exceptions import ConnectionInterrupted
 
-DJANGO_REDIS_IGNORE_EXCEPTIONS = getattr(
-    settings, "DJANGO_REDIS_IGNORE_EXCEPTIONS", False
-)
-DJANGO_REDIS_LOG_IGNORED_EXCEPTIONS = getattr(
-    settings, "DJANGO_REDIS_LOG_IGNORED_EXCEPTIONS", False
-)
-DJANGO_REDIS_LOGGER = getattr(settings, "DJANGO_REDIS_LOGGER", False)
 DJANGO_REDIS_SCAN_ITERSIZE = getattr(settings, "DJANGO_REDIS_SCAN_ITERSIZE", 10)
 
-
-if DJANGO_REDIS_LOG_IGNORED_EXCEPTIONS:
-    logger = logging.getLogger(DJANGO_REDIS_LOGGER or __name__)
-
 CONNECTION_INTERRUPTED = object()
 
 
@@ -38,8 +27,8 @@ def _decorator(self, *args, **kwargs):
             return method(self, *args, **kwargs)
         except ConnectionInterrupted as e:
             if self._ignore_exceptions:
-                if DJANGO_REDIS_LOG_IGNORED_EXCEPTIONS:
-                    logger.error(str(e))
+                if self._log_ignored_exceptions:
+                    self.logger.error(str(e))
 
                 return return_value
             raise e.__cause__
@@ -61,7 +50,16 @@ def __init__(self, server, params):
         self._client = None
 
         self._ignore_exceptions = options.get(
-            "IGNORE_EXCEPTIONS", DJANGO_REDIS_IGNORE_EXCEPTIONS
+            "IGNORE_EXCEPTIONS",
+            getattr(settings, "DJANGO_REDIS_IGNORE_EXCEPTIONS", False),
+        )
+        self._log_ignored_exceptions = getattr(
+            settings, "DJANGO_REDIS_LOG_IGNORED_EXCEPTIONS", False
+        )
+        self.logger = (
+            logging.getLogger(getattr(settings, "DJANGO_REDIS_LOGGER", __name__))
+            if self._log_ignored_exceptions
+            else None
         )
 
     @property
diff --git a/tests/test_backend.py b/tests/test_backend.py
index 31a80931..c7eee33d 100644
--- a/tests/test_backend.py
+++ b/tests/test_backend.py
@@ -706,18 +706,15 @@ def test_touch_default_timeout(self):
 
 class DjangoOmitExceptionsTests(unittest.TestCase):
     def setUp(self):
-        self._orig_setting = django_redis.cache.DJANGO_REDIS_IGNORE_EXCEPTIONS
-        django_redis.cache.DJANGO_REDIS_IGNORE_EXCEPTIONS = True
         caches_setting = copy.deepcopy(settings.CACHES)
         caches_setting["doesnotexist"]["OPTIONS"]["IGNORE_EXCEPTIONS"] = True
-        cm = override_settings(CACHES=caches_setting)
+        cm = override_settings(
+            CACHES=caches_setting, DJANGO_REDIS_IGNORE_EXCEPTIONS=True
+        )
         cm.enable()
         self.addCleanup(cm.disable)
         self.cache = caches["doesnotexist"]
 
-    def tearDown(self):
-        django_redis.cache.DJANGO_REDIS_IGNORE_EXCEPTIONS = self._orig_setting
-
     def test_get_many_returns_default_arg(self):
         self.assertIs(self.cache._ignore_exceptions, True)
         self.assertEqual(self.cache.get_many(["key1", "key2", "key3"]), {})
@@ -731,18 +728,15 @@ def test_get(self):
 
 class DjangoOmitExceptionsPriority1Tests(unittest.TestCase):
     def setUp(self):
-        self._orig_setting = django_redis.cache.DJANGO_REDIS_IGNORE_EXCEPTIONS
-        django_redis.cache.DJANGO_REDIS_IGNORE_EXCEPTIONS = False
         caches_setting = copy.deepcopy(settings.CACHES)
         caches_setting["doesnotexist"]["OPTIONS"]["IGNORE_EXCEPTIONS"] = True
-        cm = override_settings(CACHES=caches_setting)
+        cm = override_settings(
+            CACHES=caches_setting, DJANGO_REDIS_IGNORE_EXCEPTIONS=False
+        )
         cm.enable()
         self.addCleanup(cm.disable)
         self.cache = caches["doesnotexist"]
 
-    def tearDown(self):
-        django_redis.cache.DJANGO_REDIS_IGNORE_EXCEPTIONS = self._orig_setting
-
     def test_get(self):
         self.assertIs(self.cache._ignore_exceptions, True)
         self.assertIsNone(self.cache.get("key"))
@@ -750,18 +744,15 @@ def test_get(self):
 
 class DjangoOmitExceptionsPriority2Tests(unittest.TestCase):
     def setUp(self):
-        self._orig_setting = django_redis.cache.DJANGO_REDIS_IGNORE_EXCEPTIONS
-        django_redis.cache.DJANGO_REDIS_IGNORE_EXCEPTIONS = True
         caches_setting = copy.deepcopy(settings.CACHES)
         caches_setting["doesnotexist"]["OPTIONS"]["IGNORE_EXCEPTIONS"] = False
-        cm = override_settings(CACHES=caches_setting)
+        cm = override_settings(
+            CACHES=caches_setting, DJANGO_REDIS_IGNORE_EXCEPTIONS=True
+        )
         cm.enable()
         self.addCleanup(cm.disable)
         self.cache = caches["doesnotexist"]
 
-    def tearDown(self):
-        django_redis.cache.DJANGO_REDIS_IGNORE_EXCEPTIONS = self._orig_setting
-
     def test_get(self):
         self.assertIs(self.cache._ignore_exceptions, False)
         with self.assertRaises(ConnectionError):