Fix breakages from typing changes when SQA is not installed

facebook#2808 moved to PEP604 optional type annotiation. Apparently this broke some code that worked fined wiht the previously used `Optional[DBSettings]` even if `DBSettings` was not defined. I'm not entirely sure what's going on; this is more than about just delayed type annotations. Anyway, this is a hotfix that returns that code to the previous state.

ax/service/ax_client.py

@@ -13,7 +13,7 @@
 from functools import partial
 
 from logging import Logger
-from typing import Any, TypeVar
+from typing import Any, Optional, TypeVar
 
 import ax.service.utils.early_stopping as early_stopping_utils
 import numpy as np
@@ -179,7 +179,7 @@ class AxClient(WithDBSettingsBase, BestPointMixin, InstantiationBase):
     def __init__(
         self,
         generation_strategy: GenerationStrategy | None = None,
-        db_settings: DBSettings | None = None,
+        db_settings: Optional[DBSettings] = None,
         enforce_sequential_optimization: bool = True,
         random_seed: int | None = None,
         torch_device: torch.device | None = None,

ax/service/scheduler.py

@@ -14,7 +14,7 @@
 from datetime import datetime
 from logging import LoggerAdapter
 from time import sleep
-from typing import Any, cast, NamedTuple
+from typing import Any, cast, NamedTuple, Optional
 
 import ax.service.utils.early_stopping as early_stopping_utils
 from ax.analysis.analysis import Analysis, AnalysisCard
@@ -180,7 +180,7 @@ def __init__(
         experiment: Experiment,
         generation_strategy: GenerationStrategyInterface,
         options: SchedulerOptions,
-        db_settings: DBSettings | None = None,
+        db_settings: Optional[DBSettings] = None,
         _skip_experiment_save: bool = False,
     ) -> None:
         self.experiment = experiment
@@ -242,7 +242,7 @@ def from_stored_experiment(
         cls,
         experiment_name: str,
         options: SchedulerOptions,
-        db_settings: DBSettings | None = None,
+        db_settings: Optional[DBSettings] = None,
         generation_strategy: GenerationStrategy | None = None,
         reduced_state: bool = True,
         **kwargs: Any,

ax/service/tests/scheduler_test_utils.py

@@ -14,7 +14,7 @@
 from math import ceil
 from random import randint
 from tempfile import NamedTemporaryFile
-from typing import Any, cast
+from typing import Any, cast, Optional
 from unittest.mock import call, Mock, patch, PropertyMock
 
 import pandas as pd
@@ -404,7 +404,7 @@ def db_settings(self) -> DBSettings:
         return DBSettings(encoder=encoder, decoder=decoder)
 
     @property
-    def db_settings_if_always_needed(self) -> DBSettings | None:
+    def db_settings_if_always_needed(self) -> Optional[DBSettings]:
         if self.ALWAYS_USE_DB:
             return self.db_settings
         return None

ax/service/utils/with_db_settings_base.py

@@ -11,7 +11,7 @@
 from collections.abc import Iterable
 
 from logging import INFO, Logger
-from typing import Any
+from typing import Any, Optional
 
 from ax.analysis.analysis import AnalysisCard
 
@@ -93,7 +93,7 @@ class WithDBSettingsBase:
     if `db_settings` property is set to a non-None value on the instance.
     """
 
-    _db_settings: DBSettings | None = None
+    _db_settings: Optional[DBSettings] = None
 
     # Mapping of object types to mapping of fields to override values
     # loaded objects will all be instantiated with fields set to
@@ -103,7 +103,7 @@ class WithDBSettingsBase:
 
     def __init__(
         self,
-        db_settings: DBSettings | None = None,
+        db_settings: Optional[DBSettings] = None,
         logging_level: int = INFO,
         suppress_all_errors: bool = False,
     ) -> None:
@@ -123,7 +123,7 @@ def __init__(
         logger.setLevel(logging_level)
 
     @staticmethod
-    def _get_default_db_settings() -> DBSettings | None:
+    def _get_default_db_settings() -> Optional[DBSettings]:
         """Overridable method to get default db_settings
         if none are passed in __init__
         """