Ensure backwards compatibility when fetching a redis client

allianceauth/authentication/task_statistics/event_series.py

@@ -5,7 +5,7 @@ from typing import List, Optional
 from pytz import utc
 from redis import Redis, RedisError
 
-from django.core.cache import cache
+from allianceauth.utils.cache import get_redis_client
 
 logger = logging.getLogger(__name__)
 
@@ -39,7 +39,7 @@ class EventSeries:
     _ROOT_KEY = "ALLIANCEAUTH_EVENT_SERIES"
 
     def __init__(self, key_id: str, redis: Redis = None) -> None:
-        self._redis = cache.get_master_client() if not redis else redis
+        self._redis = get_redis_client() if not redis else redis
         try:
             if not self._redis.ping():
                 raise RuntimeError()

allianceauth/authentication/task_statistics/tests/test_event_series.py

@@ -18,7 +18,7 @@ MODULE_PATH = "allianceauth.authentication.task_statistics.event_series"
 class TestEventSeries(TestCase):
     def test_should_abort_without_redis_client(self):
         # when
-        with patch(MODULE_PATH + ".cache.get_master_client") as mock:
+        with patch(MODULE_PATH + ".get_redis_client") as mock:
             mock.return_value = None
             events = EventSeries("dummy")
         # then
@@ -27,7 +27,7 @@ class TestEventSeries(TestCase):
 
     def test_should_disable_itself_if_redis_not_available_1(self):
         # when
-        with patch(MODULE_PATH + ".cache.get_master_client") as mock_get_master_client:
+        with patch(MODULE_PATH + ".get_redis_client") as mock_get_master_client:
             mock_get_master_client.return_value.ping.side_effect = RedisError
             events = EventSeries("dummy")
         # then
@@ -36,7 +36,7 @@ class TestEventSeries(TestCase):
 
     def test_should_disable_itself_if_redis_not_available_2(self):
         # when
-        with patch(MODULE_PATH + ".cache.get_master_client") as mock_get_master_client:
+        with patch(MODULE_PATH + ".get_redis_client") as mock_get_master_client:
             mock_get_master_client.return_value.ping.return_value = False
             events = EventSeries("dummy")
         # then

allianceauth/services/modules/discord/discord_client/client.py

@@ -8,7 +8,7 @@ from uuid import uuid1
 from redis import Redis
 import requests
 
-from django.core.cache import caches
+from allianceauth.utils.cache import get_redis_client
 
 from allianceauth import __title__ as AUTH_TITLE, __url__, __version__
 
@@ -103,8 +103,7 @@ class DiscordClient:
         self._access_token = str(access_token)
         self._is_rate_limited = bool(is_rate_limited)
         if not redis:
-            default_cache = caches['default']
-            self._redis = default_cache.get_master_client()
+            self._redis = get_redis_client()
             if not isinstance(self._redis, Redis):
                 raise RuntimeError(
                     'This class requires a Redis client, but none was provided '

allianceauth/services/modules/discord/discord_client/tests/test_client.py

@@ -85,29 +85,18 @@ class TestBasicsAndHelpers(TestCase):
         client = DiscordClient(TEST_BOT_TOKEN, mock_redis, is_rate_limited=True)
         self.assertTrue(client.is_rate_limited)
 
-    @patch(MODULE_PATH + '.caches')
-    def test_use_default_redis_if_none_provided(self, mock_caches):
-        my_redis = MagicMock(spec=Redis)
-        mock_default_cache = MagicMock(**{'get_master_client.return_value': my_redis})
-        my_dict = {'default': mock_default_cache}
-        mock_caches.__getitem__.side_effect = my_dict.__getitem__
-
+    def test_use_default_redis_if_none_provided(self):
         client = DiscordClient(TEST_BOT_TOKEN)
-        self.assertTrue(mock_default_cache.get_master_client.called)
-        self.assertEqual(client._redis, my_redis)
-
-    @patch(MODULE_PATH + '.caches')
-    def test_raise_exception_if_default_cache_is_not_redis(self, mock_caches):
-        my_redis = MagicMock()
-        mock_default_cache = MagicMock(**{'get_master_client.return_value': my_redis})
-        my_dict = {'default': mock_default_cache}
-        mock_caches.__getitem__.side_effect = my_dict.__getitem__
+        self.assertIsInstance(client._redis, Redis)
 
+    @patch(MODULE_PATH + '.get_redis_client')
+    def test_raise_exception_if_redis_client_not_found(self, mock_get_redis_client):
+        # given
+        mock_get_redis_client.return_value = None
+        # when
         with self.assertRaises(RuntimeError):
             DiscordClient(TEST_BOT_TOKEN)
 
-        self.assertTrue(mock_default_cache.get_master_client.called)
-
 
 @requests_mock.Mocker()
 class TestOtherMethods(TestCase):

allianceauth/services/modules/discord/tests/piloting_tasks.py

@@ -35,17 +35,17 @@ import logging
 from uuid import uuid1
 import random
 
-from django.core.cache import caches
 from django.contrib.auth.models import User, Group
 
 from allianceauth.services.modules.discord.models import DiscordUser
+from allianceauth.utils.cache import get_redis_client
 
 logger = logging.getLogger('allianceauth')
 MAX_RUNS = 3
 
+
 def clear_cache():
-    default_cache = caches['default']
-    redis = default_cache.get_master_client()
+    redis = get_redis_client()
     redis.flushall()
     logger.info('Cache flushed')
 

allianceauth/services/modules/discord/tests/test_integration.py

@@ -14,7 +14,6 @@ from requests.exceptions import HTTPError
 import requests_mock
 
 from django.contrib.auth.models import Group, User
-from django.core.cache import caches
 from django.shortcuts import reverse
 from django.test import TransactionTestCase, TestCase
 from django.test.utils import override_settings
@@ -23,6 +22,7 @@ from allianceauth.authentication.models import State
 from allianceauth.eveonline.models import EveCharacter
 from allianceauth.notifications.models import Notification
 from allianceauth.tests.auth_utils import AuthUtils
+from allianceauth.utils.cache import get_redis_client
 
 from . import (
     TEST_GUILD_ID,
@@ -87,8 +87,7 @@ remove_guild_member_request = DiscordRequest(
 
 
 def clear_cache():
-    default_cache = caches['default']
-    redis = default_cache.get_master_client()
+    redis = get_redis_client()
     redis.flushall()
     logger.info('Cache flushed')
 
@@ -109,7 +108,6 @@ def reset_testdata():
 class TestServiceFeatures(TransactionTestCase):
     fixtures = ['disable_analytics.json']
 
-
     @classmethod
     def setUpClass(cls):
         super().setUpClass()

allianceauth/utils/cache.py

@@ -0,0 +1,21 @@
+from redis import Redis
+
+from django.core.cache import caches
+
+try:
+    import django_redis
+except ImportError:
+    django_redis = None
+
+
+def get_redis_client() -> Redis:
+    """Get the configured redis client used by Django for caching.
+
+    This function is a wrapper designed to work for both AA2 and AA3
+    and should always be used to ensure backwards compatibility.
+    """
+    try:
+        return django_redis.get_redis_connection("default")
+    except AttributeError:
+        default_cache = caches["default"]
+        return default_cache.get_master_client()

allianceauth/utils/tests/test_cache.py

@@ -0,0 +1,39 @@
+from unittest.mock import MagicMock, patch
+
+from django.test import TestCase
+
+from allianceauth.utils.cache import get_redis_client
+
+MODULE_PATH = "allianceauth.utils.cache"
+
+
+class RedisClientStub:
+    """Substitute for a Redis client."""
+
+    pass
+
+
+class TestGetRedisClient(TestCase):
+    def test_should_work_with_aa2_api(self):
+        # given
+        mock_django_cache = MagicMock()
+        mock_django_cache.get_master_client.return_value = RedisClientStub()
+        # when
+        with patch(MODULE_PATH + ".django_redis", None), patch.dict(
+            MODULE_PATH + ".caches", {"default": mock_django_cache}
+        ):
+            client = get_redis_client()
+        # then
+        self.assertIsInstance(client, RedisClientStub)
+
+    def test_should_work_with_aa3_api(self):
+        # given
+        mock_django_redis = MagicMock()
+        mock_django_redis.get_redis_connection.return_value = RedisClientStub()
+        # when
+        with patch(MODULE_PATH + ".django_redis", mock_django_redis), patch.dict(
+            MODULE_PATH + ".caches", {"default": None}
+        ):
+            client = get_redis_client()
+        # then
+        self.assertIsInstance(client, RedisClientStub)

docs/development/tech_docu/api/index.md

@@ -11,4 +11,5 @@ To reduce redundancy and help speed up development we encourage developers to ut
     eveonline
     notifications
     testutils
+    utils
 ```

docs/development/tech_docu/api/utils.rst

@@ -0,0 +1,14 @@
+=============================
+utils
+=============================
+
+Utilities and helper functions.
+
+Location: ``allianceauth.utils``
+
+cache
+===========
+
+.. automodule:: allianceauth.utils.cache
+    :members:
+    :undoc-members: