fix(flags): correctly emit feature flag events with the FF response on get_feature_flag_payload calls (#143)

* this is the fix, needs tests

* fix test

* tests

* yeah

* please work

* ran the formatter

* code review feedback

* how'd this get here

* bump version add changelog

* Update CHANGELOG.md

Co-authored-by: David Newell <d.newell1@outlook.com>

---------

Co-authored-by: David Newell <d.newell1@outlook.com>

CHANGELOG.md

@@ -1,3 +1,31 @@
+## 3.7.4 - 2024-11-25
+
+1. Fix bug where this SDK incorrectly sent feature flag events with null values when calling `get_feature_flag_payload`.
+
+## 3.7.3 - 2024-11-25
+
+1. Use personless mode when sending an exception without a provided `distinct_id`.
+
+## 3.7.2 - 2024-11-19
+
+1. Add `type` property to exception stacks.
+
+## 3.7.1 - 2024-10-24
+
+1. Add `platform` property to each frame of exception stacks.
+
+## 3.7.0 - 2024-10-03
+
+1. Adds a new `super_properties` parameter on the client that are appended to every /capture call.
+
+## 3.6.7 - 2024-09-24
+
+1. Remove deprecated datetime.utcnow() in favour of datetime.now(tz=tzutc())
+
+## 3.6.6 - 2024-09-16
+
+1. Fix manual capture support for in app frames
+
 ## 3.6.5 - 2024-09-10
 
 1. Fix django integration support for manual exception capture.
@@ -58,7 +86,6 @@
 
 1. Return success/failure with all capture calls from module functions
 
-
 ## 3.3.1 - 2024-01-10
 
 1. Make sure we don't override any existing feature flag properties when adding locally evaluated feature flag properties.
@@ -84,6 +111,7 @@
 
 1. Restore how feature flags work when the client library is disabled: All requests return `None` and no events are sent when the client is disabled.
 2. Add a `feature_flag_definitions()` debug option, which returns currently loaded feature flag definitions. You can use this to more cleverly decide when to request local evaluation of feature flags.
+
 ## 3.0.0 - 2023-04-14
 
 Breaking change:
@@ -124,7 +152,6 @@ posthog = Posthog('api_key', disable_geoip=False)
 1. Log instead of raise error on posthog personal api key errors
 2. Remove upper bound on backoff dependency
 
-
 ## 2.3.0 - 2023-01-31
 
 1. Add support for returning payloads of matched feature flags
@@ -140,6 +167,7 @@ Changes:
 Changes:
 
 1. Fixes issues with date comparison.
+
 ## 2.1.1 - 2022-09-14
 
 Changes:
@@ -152,6 +180,7 @@ Changes:
 
 1. Feature flag defaults have been removed
 2. Setup logging only when debug mode is enabled.
+
 ## 2.0.1 - 2022-08-04
 
 - Make poll_interval configurable
@@ -164,7 +193,7 @@ Breaking changes:
 
 1. The minimum version requirement for PostHog servers is now 1.38. If you're using PostHog Cloud, you satisfy this requirement automatically.
 2. Feature flag defaults apply only when there's an error fetching feature flag results. Earlier, if the default was set to `True`, even if a flag resolved to `False`, the default would override this.
-**Note: These are removed in 2.0.2**
+   **Note: These are removed in 2.0.2**
 3. Feature flag remote evaluation doesn't require a personal API key.
 
 New Changes:
@@ -172,18 +201,20 @@ New Changes:
 1. You can now evaluate feature flags locally (i.e. without sending a request to your PostHog servers) by setting a personal API key, and passing in groups and person properties to `is_feature_enabled` and `get_feature_flag` calls.
 2. Introduces a `get_all_flags` method that returns all feature flags. This is useful for when you want to seed your frontend with some initial flags, given a user ID.
 
-
-
 ## 1.4.9 - 2022-06-13
+
 - Support for sending feature flags with capture calls
 
 ## 1.4.8 - 2022-05-12
+
 - Support multi variate feature flags
 
 ## 1.4.7 - 2022-04-25
+
 - Allow feature flags usage without project_api_key
 
 ## 1.4.1 - 2021-05-28
+
 - Fix packaging issues with Sentry integrations
 
 ## 1.4.0 - 2021-05-18

posthog/__init__.py

@@ -2,7 +2,7 @@ import datetime  # noqa: F401
 from typing import Callable, Dict, List, Optional, Tuple  # noqa: F401
 
 from posthog.client import Client
-from posthog.exception_capture import DEFAULT_DISTINCT_ID, Integrations  # noqa: F401
+from posthog.exception_capture import Integrations  # noqa: F401
 from posthog.version import VERSION
 
 __version__ = VERSION
@@ -20,9 +20,12 @@ project_api_key = None  # type: Optional[str]
 poll_interval = 30  # type: int
 disable_geoip = True  # type: bool
 feature_flags_request_timeout_seconds = 3  # type: int
+super_properties = None  # type: Optional[Dict]
 # Currently alpha, use at your own risk
 enable_exception_autocapture = False  # type: bool
 exception_autocapture_integrations = []  # type: List[Integrations]
+# Used to determine in app paths for exception autocapture. Defaults to the current working directory
+project_root = None  # type: Optional[str]
 
 default_client = None  # type: Optional[Client]
 
@@ -286,7 +289,7 @@ def capture_exception(
     return _proxy(
         "capture_exception",
         exception=exception,
-        distinct_id=distinct_id or DEFAULT_DISTINCT_ID,
+        distinct_id=distinct_id,
         properties=properties,
         context=context,
         timestamp=timestamp,
@@ -502,6 +505,7 @@ def _proxy(method, *args, **kwargs):
             disabled=disabled,
             disable_geoip=disable_geoip,
             feature_flags_request_timeout_seconds=feature_flags_request_timeout_seconds,
+            super_properties=super_properties,
             # TODO: Currently this monitoring begins only when the Client is initialised (which happens when you do something with the SDK)
             # This kind of initialisation is very annoying for exception capture. We need to figure out a way around this,
             # or deprecate this proxy option fully (it's already in the process of deprecation, no new clients should be using this method since like 5-6 months)

posthog/client.py

@@ -1,15 +1,16 @@
 import atexit
 import logging
 import numbers
+import os
 import sys
 from datetime import datetime, timedelta
-from uuid import UUID
+from uuid import UUID, uuid4
 
 from dateutil.tz import tzutc
 from six import string_types
 
 from posthog.consumer import Consumer
-from posthog.exception_capture import DEFAULT_DISTINCT_ID, ExceptionCapture
+from posthog.exception_capture import ExceptionCapture
 from posthog.exception_utils import exc_info_from_error, exceptions_from_error_tuple, handle_in_app
 from posthog.feature_flags import InconclusiveMatchError, match_feature_flag_properties
 from posthog.poller import Poller
@@ -54,8 +55,10 @@ class Client(object):
         disable_geoip=True,
         historical_migration=False,
         feature_flags_request_timeout_seconds=3,
+        super_properties=None,
         enable_exception_autocapture=False,
         exception_autocapture_integrations=None,
+        project_root=None,
     ):
         self.queue = queue.Queue(max_queue_size)
 
@@ -84,10 +87,19 @@ class Client(object):
         self.disabled = disabled
         self.disable_geoip = disable_geoip
         self.historical_migration = historical_migration
+        self.super_properties = super_properties
         self.enable_exception_autocapture = enable_exception_autocapture
         self.exception_autocapture_integrations = exception_autocapture_integrations
         self.exception_capture = None
 
+        if project_root is None:
+            try:
+                project_root = os.getcwd()
+            except Exception:
+                project_root = None
+
+        self.project_root = project_root
+
         # personal_api_key: This should be a generated Personal API Key, private
         self.personal_api_key = personal_api_key
         if debug:
@@ -161,6 +173,15 @@ class Client(object):
         resp_data = self.get_decide(distinct_id, groups, person_properties, group_properties, disable_geoip)
         return resp_data["featureFlagPayloads"]
 
+    def get_feature_flags_and_payloads(
+        self, distinct_id, groups=None, person_properties=None, group_properties=None, disable_geoip=None
+    ):
+        resp_data = self.get_decide(distinct_id, groups, person_properties, group_properties, disable_geoip)
+        return {
+            "featureFlags": resp_data["featureFlags"],
+            "featureFlagPayloads": resp_data["featureFlagPayloads"],
+        }
+
     def get_decide(self, distinct_id, groups=None, person_properties=None, group_properties=None, disable_geoip=None):
         require("distinct_id", distinct_id, ID_TYPES)
 
@@ -350,7 +371,7 @@ class Client(object):
     def capture_exception(
         self,
         exception=None,
-        distinct_id=DEFAULT_DISTINCT_ID,
+        distinct_id=None,
         properties=None,
         context=None,
         timestamp=None,
@@ -361,6 +382,13 @@ class Client(object):
         # this is important to ensure we don't unexpectedly re-raise exceptions in the user's code.
         try:
             properties = properties or {}
+
+            # if there's no distinct_id, we'll generate one and set personless mode
+            # via $process_person_profile = false
+            if distinct_id is None:
+                properties["$process_person_profile"] = False
+                distinct_id = uuid4()
+
             require("distinct_id", distinct_id, ID_TYPES)
             require("properties", properties, dict)
 
@@ -373,7 +401,7 @@ class Client(object):
                 self.log.warning("No exception information available")
                 return
 
-            # Format stack trace like sentry
+            # Format stack trace for cymbal
             all_exceptions_with_trace = exceptions_from_error_tuple(exc_info)
 
             # Add in-app property to frames in the exceptions
@@ -382,7 +410,8 @@ class Client(object):
                     "exception": {
                         "values": all_exceptions_with_trace,
                     },
-                }
+                },
+                project_root=self.project_root,
             )
             all_exceptions_with_trace_and_in_app = event["exception"]["values"]
 
@@ -406,7 +435,7 @@ class Client(object):
 
         timestamp = msg["timestamp"]
         if timestamp is None:
-            timestamp = datetime.utcnow().replace(tzinfo=tzutc())
+            timestamp = datetime.now(tz=tzutc())
 
         require("timestamp", timestamp, datetime)
         require("context", msg["context"], dict)
@@ -432,6 +461,9 @@ class Client(object):
         if disable_geoip:
             msg["properties"]["$geoip_disable"] = True
 
+        if self.super_properties:
+            msg["properties"] = {**msg["properties"], **self.super_properties}
+
         msg["distinct_id"] = stringify_id(msg.get("distinct_id", None))
 
         msg = clean(msg)
@@ -530,7 +562,7 @@ class Client(object):
             )
             self.log.warning(e)
 
-        self._last_feature_flag_poll = datetime.utcnow().replace(tzinfo=tzutc())
+        self._last_feature_flag_poll = datetime.now(tz=tzutc())
 
     def load_feature_flags(self):
         if not self.personal_api_key:
@@ -723,23 +755,52 @@ class Client(object):
                 groups=groups,
                 person_properties=person_properties,
                 group_properties=group_properties,
-                send_feature_flag_events=send_feature_flag_events,
-                only_evaluate_locally=True,
+                send_feature_flag_events=False,
+                # Disable automatic sending of feature flag events because we're manually handling event dispatch.
+                # This prevents sending events with empty data when `get_feature_flag` cannot be evaluated locally.
+                only_evaluate_locally=True,  # Enable local evaluation of feature flags to avoid making multiple requests to `/decide`.
                 disable_geoip=disable_geoip,
             )
 
         response = None
+        payload = None
 
         if match_value is not None:
-            response = self._compute_payload_locally(key, match_value)
+            payload = self._compute_payload_locally(key, match_value)
 
-        if response is None and not only_evaluate_locally:
-            decide_payloads = self.get_feature_payloads(
-                distinct_id, groups, person_properties, group_properties, disable_geoip
+        flag_was_locally_evaluated = payload is not None
+        if not flag_was_locally_evaluated and not only_evaluate_locally:
+            try:
+                responses_and_payloads = self.get_feature_flags_and_payloads(
+                    distinct_id, groups, person_properties, group_properties, disable_geoip
+                )
+                response = responses_and_payloads["featureFlags"].get(key, None)
+                payload = responses_and_payloads["featureFlagPayloads"].get(str(key).lower(), None)
+            except Exception as e:
+                self.log.exception(f"[FEATURE FLAGS] Unable to get feature flags and payloads: {e}")
+
+        feature_flag_reported_key = f"{key}_{str(response)}"
+
+        if (
+            feature_flag_reported_key not in self.distinct_ids_feature_flags_reported[distinct_id]
+            and send_feature_flag_events  # noqa: W503
+        ):
+            self.capture(
+                distinct_id,
+                "$feature_flag_called",
+                {
+                    "$feature_flag": key,
+                    "$feature_flag_response": response,
+                    "$feature_flag_payload": payload,
+                    "locally_evaluated": flag_was_locally_evaluated,
+                    f"$feature/{key}": response,
+                },
+                groups=groups,
+                disable_geoip=disable_geoip,
             )
-            response = decide_payloads.get(str(key).lower(), None)
+            self.distinct_ids_feature_flags_reported[distinct_id].add(feature_flag_reported_key)
 
-        return response
+        return payload
 
     def _compute_payload_locally(self, key, match_value):
         payload = None

posthog/exception_capture.py

@@ -12,9 +12,6 @@ class Integrations(str, Enum):
     Django = "django"
 
 
-DEFAULT_DISTINCT_ID = "python-exceptions"
-
-
 class ExceptionCapture:
     # TODO: Add client side rate limiting to prevent spamming the server with exceptions
 
@@ -61,14 +58,7 @@ class ExceptionCapture:
 
     def capture_exception(self, exception, metadata=None):
         try:
-            # if hasattr(sys, "ps1"):
-            #     # Disable the excepthook for interactive Python shells
-            #     return
-
-            distinct_id = metadata.get("distinct_id") if metadata else DEFAULT_DISTINCT_ID
-            # Make sure we have a distinct_id if its empty in metadata
-            distinct_id = distinct_id or DEFAULT_DISTINCT_ID
-
+            distinct_id = metadata.get("distinct_id") if metadata else None
             self.client.capture_exception(exception, distinct_id)
         except Exception as e:
             self.log.exception(f"Failed to capture exception: {e}")

posthog/exception_utils.py

@@ -369,6 +369,7 @@ def serialize_frame(
         tb_lineno = frame.f_lineno
 
     rv = {
+        "platform": "python",
         "filename": filename_for_module(module, abs_path) or None,
         "abs_path": os.path.abspath(abs_path) if abs_path else None,
         "function": function or "<unknown>",
@@ -417,7 +418,7 @@ def current_stacktrace(
 
     frames.reverse()
 
-    return {"frames": frames}
+    return {"frames": frames, "type": "raw"}
 
 
 def get_errno(exc_value):
@@ -503,7 +504,7 @@ def single_exception_from_error_tuple(
     ]
 
     if frames:
-        exception_value["stacktrace"] = {"frames": frames}
+        exception_value["stacktrace"] = {"frames": frames, "type": "raw"}
 
     return exception_value
 

posthog/request.py

@@ -37,7 +37,7 @@ def post(
     """Post the `kwargs` to the API"""
     log = logging.getLogger("posthog")
     body = kwargs
-    body["sentAt"] = datetime.utcnow().replace(tzinfo=tzutc()).isoformat()
+    body["sentAt"] = datetime.now(tz=tzutc()).isoformat()
     url = remove_trailing_slash(host or DEFAULT_HOST) + path
     body["api_key"] = api_key
     data = json.dumps(body, cls=DatetimeSerializer)

posthog/test/test_client.py

@@ -84,16 +84,31 @@ class TestClient(unittest.TestCase):
         self.assertEqual(msg["properties"]["$lib"], "posthog-python")
         self.assertEqual(msg["properties"]["$lib_version"], VERSION)
 
+    def test_basic_super_properties(self):
+        client = Client(FAKE_TEST_API_KEY, super_properties={"source": "repo-name"})
+
+        _, msg = client.capture("distinct_id", "python test event")
+        client.flush()
+
+        self.assertEqual(msg["event"], "python test event")
+        self.assertEqual(msg["properties"]["source"], "repo-name")
+
+        _, msg = client.identify("distinct_id", {"trait": "value"})
+        client.flush()
+
+        self.assertEqual(msg["$set"]["trait"], "value")
+        self.assertEqual(msg["properties"]["source"], "repo-name")
+
     def test_basic_capture_exception(self):
 
         with mock.patch.object(Client, "capture", return_value=None) as patch_capture:
             client = self.client
             exception = Exception("test exception")
-            client.capture_exception(exception)
+            client.capture_exception(exception, distinct_id="distinct_id")
 
             self.assertTrue(patch_capture.called)
             capture_call = patch_capture.call_args[0]
-            self.assertEqual(capture_call[0], "python-exceptions")
+            self.assertEqual(capture_call[0], "distinct_id")
             self.assertEqual(capture_call[1], "$exception")
             self.assertEqual(
                 capture_call[2],
@@ -108,7 +123,7 @@ class TestClient(unittest.TestCase):
                             "value": "test exception",
                         }
                     ],
-                    "$exception_personURL": "https://us.i.posthog.com/project/random_key/person/python-exceptions",
+                    "$exception_personURL": "https://us.i.posthog.com/project/random_key/person/distinct_id",
                 },
             )
 
@@ -203,11 +218,11 @@ class TestClient(unittest.TestCase):
             try:
                 raise Exception("test exception")
             except Exception:
-                client.capture_exception()
+                client.capture_exception(distinct_id="distinct_id")
 
             self.assertTrue(patch_capture.called)
             capture_call = patch_capture.call_args[0]
-            self.assertEqual(capture_call[0], "python-exceptions")
+            self.assertEqual(capture_call[0], "distinct_id")
             self.assertEqual(capture_call[1], "$exception")
             self.assertEqual(capture_call[2]["$exception_type"], "Exception")
             self.assertEqual(capture_call[2]["$exception_message"], "test exception")
@@ -216,6 +231,10 @@ class TestClient(unittest.TestCase):
             self.assertEqual(capture_call[2]["$exception_list"][0]["module"], None)
             self.assertEqual(capture_call[2]["$exception_list"][0]["type"], "Exception")
             self.assertEqual(capture_call[2]["$exception_list"][0]["value"], "test exception")
+            self.assertEqual(
+                capture_call[2]["$exception_list"][0]["stacktrace"]["type"],
+                "raw",
+            )
             self.assertEqual(
                 capture_call[2]["$exception_list"][0]["stacktrace"]["frames"][0]["filename"],
                 "posthog/test/test_client.py",
@@ -227,6 +246,7 @@ class TestClient(unittest.TestCase):
             self.assertEqual(
                 capture_call[2]["$exception_list"][0]["stacktrace"]["frames"][0]["module"], "posthog.test.test_client"
             )
+            self.assertEqual(capture_call[2]["$exception_list"][0]["stacktrace"]["frames"][0]["in_app"], True)
 
     def test_basic_capture_exception_with_no_exception_happening(self):
 

posthog/test/test_exception_capture.py

@@ -29,7 +29,7 @@ def test_excepthook(tmpdir):
     assert b"LOL" in output
     assert b"DEBUG:posthog:data uploaded successfully" in output
     assert (
-        b'"$exception_list": [{"mechanism": {"type": "generic", "handled": true}, "module": null, "type": "ZeroDivisionError", "value": "division by zero", "stacktrace": {"frames": [{"filename": "app.py", "abs_path"'
+        b'"$exception_list": [{"mechanism": {"type": "generic", "handled": true}, "module": null, "type": "ZeroDivisionError", "value": "division by zero", "stacktrace": {"frames": [{"platform": "python", "filename": "app.py", "abs_path"'
         in output
     )
 
@@ -58,6 +58,6 @@ def test_trying_to_use_django_integration(tmpdir):
     assert b"LOL" in output
     assert b"DEBUG:posthog:data uploaded successfully" in output
     assert (
-        b'"$exception_list": [{"mechanism": {"type": "generic", "handled": true}, "module": null, "type": "ZeroDivisionError", "value": "division by zero", "stacktrace": {"frames": [{"filename": "app.py", "abs_path"'
+        b'"$exception_list": [{"mechanism": {"type": "generic", "handled": true}, "module": null, "type": "ZeroDivisionError", "value": "division by zero", "stacktrace": {"frames": [{"platform": "python", "filename": "app.py", "abs_path"'
         in output
     )

posthog/test/test_feature_flags.py

@@ -1632,9 +1632,10 @@ class TestLocalEvaluation(unittest.TestCase):
         )
         self.assertEqual(patch_decide.call_count, 0)
 
+    @mock.patch.object(Client, "capture")
     @mock.patch("posthog.client.decide")
-    def test_boolean_feature_flag_payload_decide(self, patch_decide):
-        patch_decide.return_value = {"featureFlagPayloads": {"person-flag": 300}}
+    def test_boolean_feature_flag_payload_decide(self, patch_decide, patch_capture):
+        patch_decide.return_value = {"featureFlags": {"person-flag": True}, "featureFlagPayloads": {"person-flag": 300}}
         self.assertEqual(
             self.client.get_feature_flag_payload(
                 "person-flag", "some-distinct-id", person_properties={"region": "USA"}
@@ -1649,6 +1650,8 @@ class TestLocalEvaluation(unittest.TestCase):
             300,
         )
         self.assertEqual(patch_decide.call_count, 2)
+        self.assertEqual(patch_capture.call_count, 1)
+        patch_capture.reset_mock()
 
     @mock.patch("posthog.client.decide")
     def test_multivariate_feature_flag_payloads(self, patch_decide):
@@ -2334,6 +2337,88 @@ class TestCaptureCalls(unittest.TestCase):
             disable_geoip=None,
         )
 
+    @mock.patch.object(Client, "capture")
+    @mock.patch("posthog.client.decide")
+    def test_capture_is_called_in_get_feature_flag_payload(self, patch_decide, patch_capture):
+        patch_decide.return_value = {
+            "featureFlags": {"person-flag": True},
+            "featureFlagPayloads": {"person-flag": 300},
+        }
+        client = Client(api_key=FAKE_TEST_API_KEY, personal_api_key=FAKE_TEST_API_KEY)
+
+        client.feature_flags = [
+            {
+                "id": 1,
+                "name": "Beta Feature",
+                "key": "person-flag",
+                "is_simple_flag": False,
+                "active": True,
+                "filters": {
+                    "groups": [
+                        {
+                            "properties": [{"key": "region", "value": "USA"}],
+                            "rollout_percentage": 100,
+                        }
+                    ],
+                },
+            }
+        ]
+
+        # Call get_feature_flag_payload with match_value=None to trigger get_feature_flag
+        client.get_feature_flag_payload(
+            key="person-flag", distinct_id="some-distinct-id", person_properties={"region": "USA", "name": "Aloha"}
+        )
+
+        # Assert that capture was called once, with the correct parameters
+        self.assertEqual(patch_capture.call_count, 1)
+        patch_capture.assert_called_with(
+            "some-distinct-id",
+            "$feature_flag_called",
+            {
+                "$feature_flag": "person-flag",
+                "$feature_flag_response": True,
+                "$feature_flag_payload": 300,
+                "locally_evaluated": False,
+                "$feature/person-flag": True,
+            },
+            groups={},
+            disable_geoip=None,
+        )
+
+        # Reset mocks for further tests
+        patch_capture.reset_mock()
+        patch_decide.reset_mock()
+
+        # Call get_feature_flag_payload again for the same user; capture should not be called again because we've already reported an event for this distinct_id + flag
+        client.get_feature_flag_payload(
+            key="person-flag", distinct_id="some-distinct-id", person_properties={"region": "USA", "name": "Aloha"}
+        )
+
+        self.assertEqual(patch_capture.call_count, 0)
+        patch_capture.reset_mock()
+
+        # Call get_feature_flag_payload for a different user; capture should be called
+        client.get_feature_flag_payload(
+            key="person-flag", distinct_id="some-distinct-id2", person_properties={"region": "USA", "name": "Aloha"}
+        )
+
+        self.assertEqual(patch_capture.call_count, 1)
+        patch_capture.assert_called_with(
+            "some-distinct-id2",
+            "$feature_flag_called",
+            {
+                "$feature_flag": "person-flag",
+                "$feature_flag_response": True,
+                "$feature_flag_payload": 300,
+                "locally_evaluated": False,
+                "$feature/person-flag": True,
+            },
+            groups={},
+            disable_geoip=None,
+        )
+
+        patch_capture.reset_mock()
+
     @mock.patch.object(Client, "capture")
     @mock.patch("posthog.client.decide")
     def test_disable_geoip_get_flag_capture_call(self, patch_decide, patch_capture):

posthog/version.py

@@ -1,4 +1,4 @@
-VERSION = "3.6.5"
+VERSION = "3.7.3"
 
 if __name__ == "__main__":
     print(VERSION, end="")  # noqa: T201