fix(flags): accept rediss:// URLs for flag_fallback_cache_url

.sampo/changesets/flag-cache-rediss-scheme.md

@@ -0,0 +1,5 @@
+---
+pypi/posthog: patch
+---
+
+Accept rediss:// URLs in flag_fallback_cache_url so the flag fallback cache can use Redis over TLS.

posthog/client.py

@@ -4823,6 +4823,7 @@ def _initialize_flag_cache(self, cache_url):
                 - "memory://local/?ttl=300&size=10000": Memory cache with TTL and size
                 - "redis://localhost:6379/0/?ttl=300": Redis cache with TTL
                 - "redis://username:password@host:port/?ttl=300": Redis with auth
+                - "rediss://username:password@host:port/?ttl=300": Redis over TLS
 
         Example usage:
             # Memory cache
@@ -4858,7 +4859,7 @@ def _initialize_flag_cache(self, cache_url):
                 size = int(query_params.get("size", [10000])[0])
                 return FlagCache(size, ttl)
 
-            elif scheme == "redis":
+            elif scheme in ("redis", "rediss"):
                 try:
                     # Not worth importing redis if we're not using it
                     import redis
@@ -4891,7 +4892,7 @@ def _initialize_flag_cache(self, cache_url):
                     return None
             else:
                 raise ValueError(
-                    f"Unknown cache URL scheme: {scheme}. Supported schemes: memory, redis"
+                    f"Unknown cache URL scheme: {scheme}. Supported schemes: memory, redis, rediss"
                 )
 
         except Exception as e:

posthog/test/test_client.py

@@ -24,6 +24,7 @@
 from posthog.test.logging_helpers import capture_message_only_logs
 from posthog.test.test_utils import FAKE_TEST_API_KEY
 from posthog.types import FeatureFlag, FeatureFlagResult, LegacyFlagMetadata
+from posthog.utils import RedisFlagCache
 from posthog.version import VERSION
 from posthog.contexts import tag
 
@@ -2589,6 +2590,32 @@ def test_shutdown_clears_feature_flag_called_dedupe_cache(self):
 
         self.assertEqual(len(client.distinct_ids_feature_flags_reported), 0)
 
+    @parameterized.expand(
+        [
+            ("redis://localhost:6379/0/?ttl=120", "redis://localhost:6379/0/"),
+            (
+                "rediss://user:[email protected]:6380/1?ttl=120",
+                "rediss://user:[email protected]:6380/1",
+            ),
+        ]
+    )
+    def test_flag_fallback_cache_url_accepts_redis_schemes(
+        self, cache_url, expected_redis_url
+    ):
+        fake_redis = mock.Mock()
+        with mock.patch.dict(sys.modules, {"redis": fake_redis}):
+            client = Client(
+                FAKE_TEST_API_KEY,
+                send=False,
+                thread=0,
+                flag_fallback_cache_url=cache_url,
+            )
+
+        fake_redis.from_url.assert_called_once_with(expected_redis_url)
+        self.assertIsInstance(client.flag_cache, RedisFlagCache)
+        self.assertEqual(client.flag_cache.default_ttl, 120)
+        client.shutdown()
+
     def test_shutdown_flushes_without_timeout(self):
         client = Client(FAKE_TEST_API_KEY, flush_interval=0.01)