fix: KeyError when last_sign_in_time does not exist in token_data

src/firebase_functions/private/_identity_fn.py

@@ -65,10 +65,12 @@ def _auth_user_info_from_token_data(token_data: dict[str, _typing.Any]):
 def _auth_user_metadata_from_token_data(token_data: dict[str, _typing.Any]):
     from firebase_functions.identity_fn import AuthUserMetadata
     creation_time = int(token_data["creation_time"]) / 1000.0
-    last_sign_in_time = int(token_data["last_sign_in_time"]) / 1000.0
+    last_sign_in_time = None
+    if "last_sign_in_time" in token_data:
+        last_sign_in_time = int(token_data["last_sign_in_time"]) / 1000.0
     return AuthUserMetadata(
         creation_time=_dt.datetime.utcfromtimestamp(creation_time),
-        last_sign_in_time=_dt.datetime.utcfromtimestamp(last_sign_in_time),
+        last_sign_in_time=_dt.datetime.utcfromtimestamp(last_sign_in_time) if last_sign_in_time else None,
     )
 
 
@@ -89,7 +91,7 @@ def _auth_multi_factor_info_from_token_data(token_data: dict[str, _typing.Any]):
 
 
 def _auth_multi_factor_settings_from_token_data(token_data: dict[str,
-                                                                 _typing.Any]):
+_typing.Any]):
     if not token_data:
         return None
 
@@ -214,14 +216,14 @@ def _auth_blocking_event_from_token_data(token_data: dict[str, _typing.Any]):
 
 
 def _validate_auth_response(
-    event_type: str,
-    auth_response,
+        event_type: str,
+        auth_response,
 ) -> dict[str, _typing.Any]:
     if auth_response is None:
         auth_response = {}
 
     custom_claims: dict[str,
-                        _typing.Any] | None = auth_response.get("custom_claims")
+    _typing.Any] | None = auth_response.get("custom_claims")
     session_claims: dict[str, _typing.Any] | None = auth_response.get(
         "session_claims")
 
@@ -303,9 +305,9 @@ def _validate_auth_response(
 
 
 def before_operation_handler(
-    func: _typing.Callable,
-    event_type: str,
-    request: _Request,
+        func: _typing.Callable,
+        event_type: str,
+        request: _Request,
 ) -> _Response:
     from firebase_functions.identity_fn import BeforeCreateResponse, BeforeSignInResponse
     try: