feat(python): allow for listing known features (#171)

python-engine/tests/test_engine.py

@@ -1,6 +1,6 @@
 from dataclasses import asdict
 import json
-from yggdrasil_engine.engine import UnleashEngine, Variant
+from yggdrasil_engine.engine import UnleashEngine, Variant, FeatureDefinition
 import json
 import os
 
@@ -138,7 +138,6 @@ def test_increments_counts_for_yes_no_and_variants():
     assert metrics["toggles"]["testToggle"]["variants"]["disabled"] == 1
 
 
-
 def test_metrics_are_flushed_when_get_metrics_is_called():
     engine = UnleashEngine()
 
@@ -155,6 +154,7 @@ def test_metrics_are_flushed_when_get_metrics_is_called():
     metrics = engine.get_metrics()
     assert metrics is None
 
+
 def test_metrics_are_still_incremented_when_toggle_does_not_exist():
     engine = UnleashEngine()
 
@@ -164,6 +164,7 @@ def test_metrics_are_still_incremented_when_toggle_does_not_exist():
 
     assert metrics["toggles"]["aToggleSoSecretItDoesNotExist"]["yes"] == 1
 
+
 def test_yields_impression_data():
     engine = UnleashEngine()
 
@@ -172,3 +173,20 @@ def test_yields_impression_data():
     assert engine.should_emit_impression_event("Feature.A")
     assert not engine.should_emit_impression_event("Nonexisting")
 
+
+def test_list_known_toggles():
+    engine = UnleashEngine()
+
+    engine.take_state(CUSTOM_STRATEGY_STATE)
+    first_toggle = engine.list_known_toggles()[0]
+
+    assert len(engine.list_known_toggles()) == 1
+    assert first_toggle == FeatureDefinition(
+        name="Feature.A", project="default", type=None
+    )
+
+
+def test_list_empty_toggles_yields_empty_list():
+    engine = UnleashEngine()
+
+    assert engine.list_known_toggles() == []

python-engine/yggdrasil_engine/engine.py

@@ -53,15 +53,34 @@ def from_dict(data: dict) -> "Variant":
         )
 
 
+@dataclass
+class FeatureDefinition:
+    name: str
+    project: str
+    type: Optional[str]
+
+    @staticmethod
+    def from_dict(data: dict) -> "FeatureDefinition":
+        return FeatureDefinition(
+            name=data.get("name", ""),
+            project=data.get("project", ""),
+            type=data.get("type"),
+        )
+
+
+def load_feature_defs(raw_defs: List[dict]) -> List[FeatureDefinition]:
+    return [FeatureDefinition.from_dict(defn) for defn in raw_defs]
+
+
 @dataclass
 class Response:
     status_code: StatusCode
     value: Optional[any]
     error_message: Optional[str]
 
-    # this only exists to handle feature_enabled/featureEnabled
     deserializers: ClassVar[Dict[Type, Callable[[Any], Any]]] = {
         Variant: Variant.from_dict,
+        List[FeatureDefinition]: load_feature_defs,
     }
 
     @staticmethod
@@ -134,6 +153,9 @@ def __init__(self):
 
         self.lib.should_emit_impression_event.restype = ctypes.POINTER(ctypes.c_char)
 
+        self.lib.list_known_toggles.argtypes = [ctypes.c_void_p]
+        self.lib.list_known_toggles.restype = ctypes.POINTER(ctypes.c_char)
+
         self.state = self.lib.new_engine()
         self.custom_strategy_handler = CustomStrategyHandler()
 
@@ -227,4 +249,13 @@ def should_emit_impression_event(self, toggle_name: str) -> bool:
         with self.materialize_pointer(response_ptr, bool) as response:
             if response.status_code == StatusCode.ERROR:
                 raise YggdrasilError(response.error_message)
-            return response.value
+            return response.value
+
+    def list_known_toggles(self) -> List[FeatureDefinition]:
+        response_ptr = self.lib.list_known_toggles(self.state)
+        with self.materialize_pointer(
+            response_ptr, List[FeatureDefinition]
+        ) as response:
+            if response.status_code == StatusCode.ERROR:
+                raise YggdrasilError(response.error_message)
+            return response.value