From 6b7bf5dcf27daae03f7c38c628c41d4488df9f8f Mon Sep 17 00:00:00 2001
From: Joe Haines <hello@joehaines.co.uk>
Date: Fri, 21 Jul 2023 10:16:45 +0100
Subject: [PATCH] Add feature flag API to Event

---
 bugsnag/event.py    | 27 +++++++++++++-
 tests/test_event.py | 91 +++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 116 insertions(+), 2 deletions(-)

diff --git a/bugsnag/event.py b/bugsnag/event.py
index 0d9e8351..990894c0 100644
--- a/bugsnag/event.py
+++ b/bugsnag/event.py
@@ -1,4 +1,4 @@
-from typing import Any, Dict, Optional, List  # noqa
+from typing import Any, Dict, Optional, List, Union  # noqa
 import linecache
 import logging
 import os
@@ -14,6 +14,7 @@
 from bugsnag.utils import fully_qualified_class_name as class_name
 from bugsnag.utils import FilterDict, package_version, SanitizingJSONEncoder
 from bugsnag.error import Error
+from bugsnag.feature_flags import FeatureFlag, FeatureFlagDelegate
 
 __all__ = ('Event',)
 
@@ -65,6 +66,7 @@ def __init__(self, exception: BaseException, config, request_config,
         self._breadcrumbs = [
             deepcopy(breadcrumb) for breadcrumb in config.breadcrumbs
         ]
+        self._feature_flag_delegate = FeatureFlagDelegate()
 
         def get_config(key):
             return options.pop(key, getattr(self.config, key))
@@ -237,6 +239,26 @@ def add_tab(self, name, dictionary):
 
         self.metadata[name].update(dictionary)
 
+    @property
+    def feature_flags(self) -> List[FeatureFlag]:
+        return self._feature_flag_delegate.to_list()
+
+    def add_feature_flag(
+        self,
+        name: Union[str, bytes],
+        variant: Union[None, str, bytes] = None
+    ) -> None:
+        self._feature_flag_delegate.add(name, variant)
+
+    def add_feature_flags(self, feature_flags: List[FeatureFlag]) -> None:
+        self._feature_flag_delegate.merge(feature_flags)
+
+    def clear_feature_flag(self, name: Union[str, bytes]) -> None:
+        self._feature_flag_delegate.remove(name)
+
+    def clear_feature_flags(self) -> None:
+        self._feature_flag_delegate.clear()
+
     def _generate_error_list(
         self,
         exception: BaseException,
@@ -437,6 +459,7 @@ def _payload(self):
                 "session": self.session,
                 "breadcrumbs": [
                     breadcrumb.to_dict() for breadcrumb in self._breadcrumbs
-                ]
+                ],
+                "featureFlags": self._feature_flag_delegate.to_json()
             }]
         })
diff --git a/tests/test_event.py b/tests/test_event.py
index 7eda818b..68bf126c 100644
--- a/tests/test_event.py
+++ b/tests/test_event.py
@@ -9,6 +9,7 @@
 from bugsnag.breadcrumbs import Breadcrumb, BreadcrumbType
 from bugsnag.configuration import Configuration
 from bugsnag.event import Event
+from bugsnag.feature_flags import FeatureFlag
 from tests import fixtures
 
 
@@ -448,3 +449,93 @@ def test_breadcrumb_array_is_always_in_payload(self):
         payload = json.loads(event._payload())
 
         assert payload['events'][0]['breadcrumbs'] == []
+
+    def test_feature_flags_can_be_added_individually(self):
+        config = Configuration()
+        event = self.event_class(Exception('oops'), config, {})
+
+        assert event.feature_flags == []
+
+        event.add_feature_flag('one')
+        event.add_feature_flag('two', 'a')
+        event.add_feature_flag('three', None)
+
+        assert event.feature_flags == [
+            FeatureFlag('one'),
+            FeatureFlag('two', 'a'),
+            FeatureFlag('three')
+        ]
+
+    def test_feature_flags_can_be_added_in_bulk(self):
+        config = Configuration()
+        event = self.event_class(Exception('oops'), config, {})
+
+        assert event.feature_flags == []
+
+        event.add_feature_flags([
+            FeatureFlag('a', '1'),
+            FeatureFlag('b'),
+            FeatureFlag('c', '3')
+        ])
+
+        assert event.feature_flags == [
+            FeatureFlag('a', '1'),
+            FeatureFlag('b'),
+            FeatureFlag('c', '3')
+        ]
+
+    def test_feature_flags_can_be_removed_individually(self):
+        config = Configuration()
+        event = self.event_class(Exception('oops'), config, {})
+
+        assert event.feature_flags == []
+
+        event.add_feature_flags([
+            FeatureFlag('a', '1'),
+            FeatureFlag('b'),
+            FeatureFlag('c', '3')
+        ])
+
+        event.clear_feature_flag('b')
+
+        assert event.feature_flags == [
+            FeatureFlag('a', '1'),
+            FeatureFlag('c', '3')
+        ]
+
+    def test_feature_flags_can_be_cleared(self):
+        config = Configuration()
+        event = self.event_class(Exception('oops'), config, {})
+
+        assert event.feature_flags == []
+
+        event.add_feature_flags([
+            FeatureFlag('a', '1'),
+            FeatureFlag('b'),
+            FeatureFlag('c', '3')
+        ])
+
+        event.clear_feature_flags()
+
+        assert event.feature_flags == []
+
+    def test_feature_flags_are_included_in_payload(self):
+        config = Configuration()
+        event = self.event_class(Exception('oops'), config, {})
+
+        assert event.feature_flags == []
+
+        event.add_feature_flags([
+            FeatureFlag('a', '1'),
+            FeatureFlag('b'),
+            FeatureFlag('c', '3')
+        ])
+
+        payload = json.loads(event._payload())
+        feature_flags = payload['events'][0]['featureFlags']
+
+        assert feature_flags == [
+            {'name': 'a', 'variant': '1'},
+            {'name': 'b'},
+            {'name': 'c', 'variant': '3'}
+        ]