refactor(idemptonency): slight performance tuning

make configure backwards compatible
resolve the full function name ahead of time

Author: Michael Brewer

aws_lambda_powertools/utilities/idempotency/persistence/base.py

@@ -112,7 +112,7 @@ class BasePersistenceLayer(ABC):
 
     def __init__(self):
         """Initialize the defaults"""
-        self.function_name = None
+        self.function_name = ""
         self.configured = False
         self.event_key_jmespath: Optional[str] = None
         self.event_key_compiled_jmespath = None
@@ -125,16 +125,19 @@ def __init__(self):
         self._cache: Optional[LRUDict] = None
         self.hash_function = None
 
-    def configure(self, config: IdempotencyConfig, function_name: str) -> None:
+    def configure(self, config: IdempotencyConfig, function_name: Optional[str] = None) -> None:
         """
         Initialize the base persistence layer from the configuration settings
 
         Parameters
         ----------
         config: IdempotencyConfig
             Idempotency configuration settings
+        function_name: str, Optional
+            The name of the function being decorated
         """
-        self.function_name = function_name
+        self.function_name = f"{os.getenv(constants.LAMBDA_FUNCTION_NAME_ENV, 'test-func')}.{function_name or ''}"
+
         if self.configured:
             # Prevent being reconfigured multiple times
             return
@@ -180,8 +183,7 @@ def _get_hashed_idempotency_key(self, data: Dict[str, Any]) -> str:
             warnings.warn(f"No value found for idempotency_key. jmespath: {self.event_key_jmespath}")
 
         generated_hash = self._generate_hash(data=data)
-        function_name = os.getenv(constants.LAMBDA_FUNCTION_NAME_ENV, "test-func") + "." + self.function_name
-        return f"{function_name}#{generated_hash}"
+        return f"{self.function_name}#{generated_hash}"
 
     @staticmethod
     def is_missing_idempotency_key(data) -> bool:

tests/functional/idempotency/test_idempotency.py

@@ -648,7 +648,7 @@ def test_in_progress_never_saved_to_cache(
 ):
     # GIVEN a data record with status "INPROGRESS"
     # and persistence_store has use_local_cache = True
-    persistence_store.configure(idempotency_config, "handler")
+    persistence_store.configure(idempotency_config)
     data_record = DataRecord("key", status="INPROGRESS")
 
     # WHEN saving to local cache
@@ -661,7 +661,7 @@ def test_in_progress_never_saved_to_cache(
 @pytest.mark.parametrize("idempotency_config", [{"use_local_cache": False}], indirect=True)
 def test_user_local_disabled(idempotency_config: IdempotencyConfig, persistence_store: DynamoDBPersistenceLayer):
     # GIVEN a persistence_store with use_local_cache = False
-    persistence_store.configure(idempotency_config, "")
+    persistence_store.configure(idempotency_config)
 
     # WHEN calling any local cache options
     data_record = DataRecord("key", status="COMPLETED")
@@ -683,7 +683,7 @@ def test_delete_from_cache_when_empty(
     idempotency_config: IdempotencyConfig, persistence_store: DynamoDBPersistenceLayer
 ):
     # GIVEN use_local_cache is True AND the local cache is empty
-    persistence_store.configure(idempotency_config, "handler")
+    persistence_store.configure(idempotency_config)
 
     try:
         # WHEN we _delete_from_cache
@@ -755,7 +755,7 @@ def test_raise_on_no_idempotency_key(
     idempotency_config: IdempotencyConfig, persistence_store: DynamoDBPersistenceLayer, lambda_context
 ):
     # GIVEN a persistence_store with raise_on_no_idempotency_key and no idempotency key in the request
-    persistence_store.configure(idempotency_config, "handler")
+    persistence_store.configure(idempotency_config)
     persistence_store.raise_on_no_idempotency_key = True
     assert persistence_store.use_local_cache is False
     assert "body" in persistence_store.event_key_jmespath
@@ -802,9 +802,9 @@ def test_jmespath_with_powertools_json(
 def test_custom_jmespath_function_overrides_builtin_functions(
     config_with_jmespath_options: IdempotencyConfig, persistence_store: DynamoDBPersistenceLayer, lambda_context
 ):
-    # GIVEN an persistence store with a custom jmespath_options
+    # GIVEN a persistence store with a custom jmespath_options
     # AND use a builtin powertools custom function
-    persistence_store.configure(config_with_jmespath_options, "handler")
+    persistence_store.configure(config_with_jmespath_options)
 
     with pytest.raises(jmespath.exceptions.UnknownFunctionError, match="Unknown function: powertools_json()"):
         # WHEN calling _get_hashed_idempotency_key