From 5d467db5a3ea172ddf624a7b62fe7b6c9af200f7 Mon Sep 17 00:00:00 2001
From: Tim DiLauro <tdilauro@users.noreply.github.com>
Date: Fri, 7 Jun 2024 17:36:09 -0400
Subject: [PATCH 1/8] Settings class that selectively allows environment
 variable override.

---
 src/palace/manager/util/settings.py | 140 ++++++++++++++++++++++++++++
 1 file changed, 140 insertions(+)
 create mode 100644 src/palace/manager/util/settings.py

diff --git a/src/palace/manager/util/settings.py b/src/palace/manager/util/settings.py
new file mode 100644
index 0000000000..29b1be9a68
--- /dev/null
+++ b/src/palace/manager/util/settings.py
@@ -0,0 +1,140 @@
+import functools
+from collections.abc import Callable
+from typing import Any
+
+from pydantic.env_settings import BaseSettings, SettingsSourceCallable
+from pydantic.fields import ModelField
+
+from palace.manager.core.config import CannotLoadConfiguration
+from palace.manager.util.log import LoggerMixin
+
+
+def _env_var_for(field: ModelField) -> str | None:
+    env_prefix = field.model_config.env_prefix  # type: ignore[attr-defined]
+    return (env_prefix + field.name).upper()
+
+
+def _restrict_environment(
+    env_settings: Callable[[BaseSettings], dict[str, Any]], settings: BaseSettings
+) -> dict[str, Any]:
+    """Limit environment variables to those not restricted by the `environment_override_*` settings.
+
+    :param env_settings: The environment settings source function, usually indirectly from `pydantic`..
+    :param settings: A pydantic model instance.
+    :return: A dictionary by field alias of values from the environment.
+
+    :raises CannotLoadConfiguration: Under the following conditions:
+        - A non-existent field is specified in one of the `environment_override_*` settings.
+        - A field is specified in more than one `environment_override_*` setting.
+        - A field specified in `environment_override_error_fields` is overridden in the environment
+
+    If a field is (1) specified in `environment_override_warning_fields` and (2) overridden in the
+    environment, then a warning is logged and the field is NOT overridden.
+    """
+    env_settings_by_alias = env_settings(settings)
+    if not env_settings_by_alias:
+        return env_settings_by_alias
+
+    config = settings.__config__
+    logger = settings.log  # type: ignore[attr-defined]
+
+    fields_by_name = settings.__fields__
+    fields_by_alias = {field.alias: field for name, field in fields_by_name.items()}
+    env_settings_by_name = {
+        fields_by_alias[alias].name: value
+        for alias, value in env_settings_by_alias.items()
+        if alias in fields_by_alias
+    }
+
+    warning_fields: set[str] = config.environment_override_warning_fields or set()  # type: ignore[attr-defined]
+    error_fields: set[str] = config.environment_override_error_fields or set()  # type: ignore[attr-defined]
+
+    if nonexistent_fields := (warning_fields | error_fields) - set(fields_by_name):
+        raise CannotLoadConfiguration(
+            "Only existing fields may be specified in either the `environment_override_warning_fields` "
+            "or `environment_override_error_fields` settings. The following fields do not exist: "
+            f"{nonexistent_fields}."
+        )
+    if overlapping_fields := warning_fields & error_fields:
+        raise CannotLoadConfiguration(
+            "A field may not be specified in both the `environment_override_warning_fields` and "
+            "`environment_override_error_fields` settings. The following are specified in both: "
+            f"{overlapping_fields}."
+        )
+    if warnings := set(env_settings_by_name) & warning_fields:
+        _msg = (
+            "Some `environment_override_warning_fields` are overridden in the environment. "
+            "The value from the environment will be ignored."
+        )
+        for field in (fields_by_name[name] for name in warnings):
+            _msg += f"\n  {field.name}: alias={field.alias}, env={_env_var_for(field)}"
+        logger.warning(_msg)
+
+    if errors := set(env_settings_by_name) & error_fields:
+        _msg = (
+            "Some `environment_override_error_fields` are overridden in the environment. "
+            "Please remove them from the environment or from the configuration settings."
+        )
+        for field in (fields_by_name[name] for name in errors):
+            _msg += f"\n  {field.name}: alias={field.alias}, env={_env_var_for(field)}"
+        raise CannotLoadConfiguration(_msg)
+
+    overridable_names = set(fields_by_name) - warnings - errors
+    overridable_aliases = {
+        field.alias
+        for name, field in fields_by_name.items()
+        if name in overridable_names
+    }
+
+    return {
+        alias: value
+        for alias, value in env_settings_by_alias.items()
+        if alias in overridable_aliases
+    }
+
+
+class BaseSettingsRestrictEnvOverride(BaseSettings, LoggerMixin):
+    # Fields that can be overridden by environment variables should be specified as normal.
+
+    # For non-overridable fields:
+    # - Set `const=True` on the field, if nothing should override the default..
+    # - Add the field name to one of the `environment_override_*` Config settings.
+
+    class Config:
+        # Handle environment variable overrides, depending on presence of field name in:
+        #   environment_override_error_fields: report field and raise exception; or
+        #   environment_override_warning_fields: report field and log warning.
+        # If a field is not specified in one of these lists, an override is permitted.
+        # If a field is specified in both, it is an error and an exception is raised.
+        # If a field is NOT specified in one of these lists, then an override is allowed.
+        # The exception, when raised, will be a `CannotLoadConfiguration`.
+        environment_override_error_fields: set[str] | None = None
+        environment_override_warning_fields: set[str] | None = None
+
+        # See the pydantic docs for information on these settings
+        # https://docs.pydantic.dev/usage/model_config/
+
+        # Strip whitespace from all strings
+        anystr_strip_whitespace = True
+
+        # Forbid mutation, so that its clear that settings changes will
+        # not automatically be saved to the database.
+        allow_mutation = False
+
+        # See `pydantic` documentation on adding sources.
+        # https://docs.pydantic.dev/1.10/usage/settings/#adding-sources
+        @classmethod
+        def customise_sources(
+            cls,
+            init_settings,
+            env_settings,
+            file_secret_settings,
+        ) -> tuple[SettingsSourceCallable, ...]:
+            # We have to wrap the environment settings source in our own function
+            # so that we can report on/strip out fields that are not overridable
+            # before `pydantic` sees them.
+            return (
+                init_settings,
+                functools.partial(_restrict_environment, env_settings),
+                file_secret_settings,
+            )

From 607162fe0bd61830ebe152f703694abb9c7dd118 Mon Sep 17 00:00:00 2001
From: Tim DiLauro <tdilauro@users.noreply.github.com>
Date: Fri, 7 Jun 2024 17:38:02 -0400
Subject: [PATCH 2/8] Add an Admin UI feature flags class.

---
 src/palace/manager/api/admin/config.py        | 45 +++++++++++++++++++
 .../manager/api/admin/controller/view.py      |  7 +--
 src/palace/manager/api/admin/templates.py     |  4 +-
 3 files changed, 50 insertions(+), 6 deletions(-)

diff --git a/src/palace/manager/api/admin/config.py b/src/palace/manager/api/admin/config.py
index 1bc5ad36f9..4512607740 100644
--- a/src/palace/manager/api/admin/config.py
+++ b/src/palace/manager/api/admin/config.py
@@ -2,10 +2,52 @@
 from enum import Enum
 from urllib.parse import urljoin
 
+from pydantic import Field
 from requests import RequestException
 
+from palace.manager.util.flask_util import _snake_to_camel_case
 from palace.manager.util.http import HTTP, RequestNetworkException
 from palace.manager.util.log import LoggerMixin
+from palace.manager.util.settings import BaseSettingsRestrictEnvOverride
+
+
+class AdminClientFeatureFlags(BaseSettingsRestrictEnvOverride):
+    # The following CAN be overridden by environment variables.
+    reports_only_for_sysadmins: bool = Field(
+        True,
+        description="Show inventory reports only for sysadmins.",
+    )
+
+    # The following fields CANNOT be overridden by environment variables.
+    # Setting `const=True` ensures that the default value is not overridden.
+    # Add them to the one of the `environment_override_*` Config settings
+    # below to prevent them from being overridden.
+    # NB: Overriding the `env_prefix` with `env=...` here may lead to
+    #     incorrect values in warnings and exceptions, since `env_prefix`
+    #     is used to generate the full environment variable name.
+    enable_auto_list: bool = Field(
+        True,
+        const=True,
+        description="Enable auto-list of items.",
+    )
+    show_circ_events_download: bool = Field(
+        True,
+        const=True,
+        description="Show download button for Circulation Events.",
+    )
+
+    class Config:
+        # We use lower camel case aliases, since we're sending to JavaScript.
+        alias_generator = _snake_to_camel_case
+        env_prefix = "PALACE_ADMINUI_FEATURES_"
+        env_file = ".env"
+
+        # Restrict environment variable overrides.
+        #
+        environment_override_warning_fields: set[str] | None = {
+            "enable_auto_list",
+            "show_circ_events_download",
+        }
 
 
 class OperationalMode(str, Enum):
@@ -53,6 +95,9 @@ class Configuration(LoggerMixin):
     # Cache the package version after first lookup.
     _version: str | None = None
 
+    # Admin client feature flags
+    admin_feature_flags = AdminClientFeatureFlags()
+
     @classmethod
     def operational_mode(cls) -> OperationalMode:
         return (
diff --git a/src/palace/manager/api/admin/controller/view.py b/src/palace/manager/api/admin/controller/view.py
index 606f114e0f..d1eba1825a 100644
--- a/src/palace/manager/api/admin/controller/view.py
+++ b/src/palace/manager/api/admin/controller/view.py
@@ -67,8 +67,8 @@ def __call__(self, collection, book, path=None):
         admin_js = AdminClientConfig.lookup_asset_url(key="admin_js")
         admin_css = AdminClientConfig.lookup_asset_url(key="admin_css")
 
-        # We always have local_analytics
-        show_circ_events_download = True
+        # # We always have local_analytics
+        # show_circ_events_download = True
 
         response = Response(
             flask.render_template_string(
@@ -77,12 +77,13 @@ def __call__(self, collection, book, path=None):
                 csrf_token=csrf_token,
                 sitewide_tos_href=Configuration.DEFAULT_TOS_HREF,
                 sitewide_tos_text=Configuration.DEFAULT_TOS_TEXT,
-                show_circ_events_download=show_circ_events_download,
+                show_circ_events_download=AdminClientConfig.admin_feature_flags.show_circ_events_download,
                 setting_up=setting_up,
                 email=email,
                 roles=roles,
                 admin_js=admin_js,
                 admin_css=admin_css,
+                feature_flags=AdminClientConfig.admin_feature_flags.json(by_alias=True),
             )
         )
 
diff --git a/src/palace/manager/api/admin/templates.py b/src/palace/manager/api/admin/templates.py
index 712f2e61c7..51a2e3b686 100644
--- a/src/palace/manager/api/admin/templates.py
+++ b/src/palace/manager/api/admin/templates.py
@@ -17,9 +17,7 @@
         settingUp: {{ "true" if setting_up else "false" }},
         email: "{{ email }}",
         roles: [{% for role in roles %}{"role": "{{role.role}}"{% if role.library %}, "library": "{{role.library.short_name}}"{% endif %} },{% endfor %}],
-        featureFlags: {
-          enableAutoList: true,
-        },
+        featureFlags: {{ feature_flags| safe }},
     });
   </script>
 </body>

From 43b802f80a156b05c6545b750966d093d44f51b9 Mon Sep 17 00:00:00 2001
From: Tim DiLauro <tdilauro@users.noreply.github.com>
Date: Sat, 8 Jun 2024 13:20:17 -0400
Subject: [PATCH 3/8] Build on ServiceConfiguration class.

---
 src/palace/manager/api/admin/config.py        |  27 ++--
 .../manager/api/admin/controller/view.py      |   6 +-
 src/palace/manager/util/settings.py           | 128 +++++++++---------
 tests/manager/service/test_configuration.py   |  66 +++++++++
 4 files changed, 149 insertions(+), 78 deletions(-)

diff --git a/src/palace/manager/api/admin/config.py b/src/palace/manager/api/admin/config.py
index 4512607740..570a4ea3fe 100644
--- a/src/palace/manager/api/admin/config.py
+++ b/src/palace/manager/api/admin/config.py
@@ -8,10 +8,10 @@
 from palace.manager.util.flask_util import _snake_to_camel_case
 from palace.manager.util.http import HTTP, RequestNetworkException
 from palace.manager.util.log import LoggerMixin
-from palace.manager.util.settings import BaseSettingsRestrictEnvOverride
+from palace.manager.util.settings import ServiceConfigurationWithLimitedEnvOverride
 
 
-class AdminClientFeatureFlags(BaseSettingsRestrictEnvOverride):
+class AdminClientFeatureFlags(ServiceConfigurationWithLimitedEnvOverride):
     # The following CAN be overridden by environment variables.
     reports_only_for_sysadmins: bool = Field(
         True,
@@ -37,17 +37,19 @@ class AdminClientFeatureFlags(BaseSettingsRestrictEnvOverride):
     )
 
     class Config:
-        # We use lower camel case aliases, since we're sending to JavaScript.
+        env_prefix = "PALACE_ADMINUI_FEATURE_"
+
+        # We use lower camel case aliases, since we're sending to the web.
         alias_generator = _snake_to_camel_case
-        env_prefix = "PALACE_ADMINUI_FEATURES_"
-        env_file = ".env"
 
-        # Restrict environment variable overrides.
-        #
-        environment_override_warning_fields: set[str] | None = {
+        # Add any fields that should not be overridden by environment variables here.
+        # - environment_override_warning_fields: warnings and ignore environment
+        # - environment_override_error_fields: raise exception
+        environment_override_warning_fields: set[str] = {
             "enable_auto_list",
             "show_circ_events_download",
         }
+        environment_override_error_fields: set[str] = set()
 
 
 class OperationalMode(str, Enum):
@@ -95,8 +97,15 @@ class Configuration(LoggerMixin):
     # Cache the package version after first lookup.
     _version: str | None = None
 
+    # Cache the feature flags after the first lookup.
+    _admin_ui_feature_flags: AdminClientFeatureFlags | None = None
+
     # Admin client feature flags
-    admin_feature_flags = AdminClientFeatureFlags()
+    @classmethod
+    def admin_feature_flags(cls) -> AdminClientFeatureFlags:
+        if not cls._admin_ui_feature_flags:
+            cls._admin_ui_feature_flags = AdminClientFeatureFlags()
+        return cls._admin_ui_feature_flags
 
     @classmethod
     def operational_mode(cls) -> OperationalMode:
diff --git a/src/palace/manager/api/admin/controller/view.py b/src/palace/manager/api/admin/controller/view.py
index d1eba1825a..ab6a819b59 100644
--- a/src/palace/manager/api/admin/controller/view.py
+++ b/src/palace/manager/api/admin/controller/view.py
@@ -77,13 +77,15 @@ def __call__(self, collection, book, path=None):
                 csrf_token=csrf_token,
                 sitewide_tos_href=Configuration.DEFAULT_TOS_HREF,
                 sitewide_tos_text=Configuration.DEFAULT_TOS_TEXT,
-                show_circ_events_download=AdminClientConfig.admin_feature_flags.show_circ_events_download,
+                show_circ_events_download=AdminClientConfig.admin_feature_flags().show_circ_events_download,
                 setting_up=setting_up,
                 email=email,
                 roles=roles,
                 admin_js=admin_js,
                 admin_css=admin_css,
-                feature_flags=AdminClientConfig.admin_feature_flags.json(by_alias=True),
+                feature_flags=AdminClientConfig.admin_feature_flags().json(
+                    by_alias=True
+                ),
             )
         )
 
diff --git a/src/palace/manager/util/settings.py b/src/palace/manager/util/settings.py
index 29b1be9a68..31a9eac63c 100644
--- a/src/palace/manager/util/settings.py
+++ b/src/palace/manager/util/settings.py
@@ -6,9 +6,47 @@
 from pydantic.fields import ModelField
 
 from palace.manager.core.config import CannotLoadConfiguration
+from palace.manager.service.configuration import ServiceConfiguration
 from palace.manager.util.log import LoggerMixin
 
 
+class ServiceConfigurationWithLimitedEnvOverride(ServiceConfiguration, LoggerMixin):
+    # Fields that can be overridden by environment variables should be specified as normal.
+
+    # For non-overridable fields:
+    # - Set `const=True` on the field, if nothing should override the default..
+    # - Add the field name to one of the `environment_override_*` Config settings.
+
+    class Config:
+        # Handle environment variable overrides, depending on presence of field name in:
+        #   environment_override_error_fields: report field and raise exception; or
+        #   environment_override_warning_fields: report field and log warning.
+        # If a field is not specified in one of these lists, an override is permitted.
+        # If a field is specified in both, it is an error and an exception is raised.
+        # If a field is NOT specified in one of these lists, then an override is allowed.
+        # The exception, when raised, will be a `CannotLoadConfiguration`.
+        environment_override_error_fields: set[str] | None = None
+        environment_override_warning_fields: set[str] | None = None
+
+        # See `pydantic` documentation on customizing sources.
+        # https://docs.pydantic.dev/1.10/usage/settings/#adding-sources
+        @classmethod
+        def customise_sources(
+            cls,
+            init_settings,
+            env_settings,
+            file_secret_settings,
+        ) -> tuple[SettingsSourceCallable, ...]:
+            # We have to wrap the environment settings source in our own function
+            # so that we can report on/strip out fields that are not overridable
+            # before `pydantic` sees them.
+            return (
+                init_settings,
+                functools.partial(_restrict_environment, env_settings),
+                file_secret_settings,
+            )
+
+
 def _env_var_for(field: ModelField) -> str | None:
     env_prefix = field.model_config.env_prefix  # type: ignore[attr-defined]
     return (env_prefix + field.name).upper()
@@ -31,40 +69,43 @@ def _restrict_environment(
     If a field is (1) specified in `environment_override_warning_fields` and (2) overridden in the
     environment, then a warning is logged and the field is NOT overridden.
     """
-    env_settings_by_alias = env_settings(settings)
-    if not env_settings_by_alias:
-        return env_settings_by_alias
-
     config = settings.__config__
     logger = settings.log  # type: ignore[attr-defined]
 
-    fields_by_name = settings.__fields__
-    fields_by_alias = {field.alias: field for name, field in fields_by_name.items()}
-    env_settings_by_name = {
-        fields_by_alias[alias].name: value
-        for alias, value in env_settings_by_alias.items()
-        if alias in fields_by_alias
-    }
-
     warning_fields: set[str] = config.environment_override_warning_fields or set()  # type: ignore[attr-defined]
     error_fields: set[str] = config.environment_override_error_fields or set()  # type: ignore[attr-defined]
 
+    fields_by_name = settings.__fields__
+    fields_by_alias = {field.alias: field for name, field in fields_by_name.items()}
+
     if nonexistent_fields := (warning_fields | error_fields) - set(fields_by_name):
         raise CannotLoadConfiguration(
-            "Only existing fields may be specified in either the `environment_override_warning_fields` "
-            "or `environment_override_error_fields` settings. The following fields do not exist: "
+            "Only existing fields may be specified in any of the `environment_override_*` "
+            "settings. The following are not the name of an existing field: "
             f"{nonexistent_fields}."
         )
     if overlapping_fields := warning_fields & error_fields:
         raise CannotLoadConfiguration(
-            "A field may not be specified in both the `environment_override_warning_fields` and "
-            "`environment_override_error_fields` settings. The following are specified in both: "
+            "A field may not be specified in more than one `environment_override_*` setting. "
+            "The following field names are specified in multiple settings: "
             f"{overlapping_fields}."
         )
+
+    env_settings_by_alias = env_settings(settings)
+    if not env_settings_by_alias:
+        return env_settings_by_alias
+
+    env_settings_by_name = {
+        fields_by_alias[alias].name: value
+        for alias, value in env_settings_by_alias.items()
+        if alias in fields_by_alias
+    }
+
     if warnings := set(env_settings_by_name) & warning_fields:
         _msg = (
-            "Some `environment_override_warning_fields` are overridden in the environment. "
-            "The value from the environment will be ignored."
+            "Some `environment_override_warning_fields` are overridden in the environment. Please "
+            "remove from either the environment or the `environment_override_warning_fields` setting."
+            "The value(s) from the environment will be ignored."
         )
         for field in (fields_by_name[name] for name in warnings):
             _msg += f"\n  {field.name}: alias={field.alias}, env={_env_var_for(field)}"
@@ -72,8 +113,8 @@ def _restrict_environment(
 
     if errors := set(env_settings_by_name) & error_fields:
         _msg = (
-            "Some `environment_override_error_fields` are overridden in the environment. "
-            "Please remove them from the environment or from the configuration settings."
+            "Some `environment_override_error_fields` are overridden in the environment. Please "
+            "remove from either the environment or the `environment_override_error_fields` setting."
         )
         for field in (fields_by_name[name] for name in errors):
             _msg += f"\n  {field.name}: alias={field.alias}, env={_env_var_for(field)}"
@@ -91,50 +132,3 @@ def _restrict_environment(
         for alias, value in env_settings_by_alias.items()
         if alias in overridable_aliases
     }
-
-
-class BaseSettingsRestrictEnvOverride(BaseSettings, LoggerMixin):
-    # Fields that can be overridden by environment variables should be specified as normal.
-
-    # For non-overridable fields:
-    # - Set `const=True` on the field, if nothing should override the default..
-    # - Add the field name to one of the `environment_override_*` Config settings.
-
-    class Config:
-        # Handle environment variable overrides, depending on presence of field name in:
-        #   environment_override_error_fields: report field and raise exception; or
-        #   environment_override_warning_fields: report field and log warning.
-        # If a field is not specified in one of these lists, an override is permitted.
-        # If a field is specified in both, it is an error and an exception is raised.
-        # If a field is NOT specified in one of these lists, then an override is allowed.
-        # The exception, when raised, will be a `CannotLoadConfiguration`.
-        environment_override_error_fields: set[str] | None = None
-        environment_override_warning_fields: set[str] | None = None
-
-        # See the pydantic docs for information on these settings
-        # https://docs.pydantic.dev/usage/model_config/
-
-        # Strip whitespace from all strings
-        anystr_strip_whitespace = True
-
-        # Forbid mutation, so that its clear that settings changes will
-        # not automatically be saved to the database.
-        allow_mutation = False
-
-        # See `pydantic` documentation on adding sources.
-        # https://docs.pydantic.dev/1.10/usage/settings/#adding-sources
-        @classmethod
-        def customise_sources(
-            cls,
-            init_settings,
-            env_settings,
-            file_secret_settings,
-        ) -> tuple[SettingsSourceCallable, ...]:
-            # We have to wrap the environment settings source in our own function
-            # so that we can report on/strip out fields that are not overridable
-            # before `pydantic` sees them.
-            return (
-                init_settings,
-                functools.partial(_restrict_environment, env_settings),
-                file_secret_settings,
-            )
diff --git a/tests/manager/service/test_configuration.py b/tests/manager/service/test_configuration.py
index b4ffdb79ca..068b610672 100644
--- a/tests/manager/service/test_configuration.py
+++ b/tests/manager/service/test_configuration.py
@@ -7,6 +7,7 @@
 
 from palace.manager.core.config import CannotLoadConfiguration
 from palace.manager.service.configuration import ServiceConfiguration
+from palace.manager.util.settings import ServiceConfigurationWithLimitedEnvOverride
 
 if TYPE_CHECKING:
     from pytest import MonkeyPatch
@@ -119,3 +120,68 @@ def test_exception_mutation(
             # Ignore the type error, since it tells us this is immutable,
             # and we are testing that behavior at runtime.
             config.string_with_default = "new value"  # type: ignore[misc]
+
+
+class TestServiceConfigurationWithLimitedEnvOverride:
+    def test_unknown_field(self):
+        class MockConfiguration1(ServiceConfigurationWithLimitedEnvOverride):
+            existing_field: bool = True
+
+            class Config:
+                env_prefix = "MOCK_"
+                environment_override_error_fields = {"non_existing_field"}
+
+        with pytest.raises(CannotLoadConfiguration) as exc_info:
+            MockConfiguration1()
+        assert "The following are not the name of an existing field" in str(
+            exc_info.value
+        )
+        assert "non_existing_field" in str(exc_info.value)
+
+        class MockConfiguration2(ServiceConfigurationWithLimitedEnvOverride):
+            existing_field: bool = True
+
+            class Config:
+                env_prefix = "MOCK_"
+                environment_override_warning_fields = {"non_existing_field"}
+
+        with pytest.raises(CannotLoadConfiguration) as exc_info:
+            MockConfiguration2()
+        assert "The following are not the name of an existing field" in str(
+            exc_info.value
+        )
+        assert "non_existing_field" in str(exc_info.value)
+
+    def test_overlapping_fields(self):
+        class MockConfiguration(ServiceConfigurationWithLimitedEnvOverride):
+            field: bool = True
+            overlapping_field: bool = True
+
+            class Config:
+                env_prefix = "MOCK_"
+                environment_override_error_fields = {"field", "overlapping_field"}
+                environment_override_warning_fields = {"overlapping_field"}
+
+        with pytest.raises(CannotLoadConfiguration) as exc_info:
+            MockConfiguration()
+        assert "The following field names are specified in multiple settings" in str(
+            exc_info.value
+        )
+        assert "overlapping_field" in str(exc_info.value)
+
+    def test_environment_override_warning_fields(
+        self,
+        caplog: pytest.LogCaptureFixture,
+        service_configuration_fixture: ServiceConfigurationFixture,
+    ):
+        class MockConfiguration(ServiceConfigurationWithLimitedEnvOverride):
+            field: bool = True
+            warning_field1: bool = True
+            warning_field2: bool = True
+
+            class Config:
+                env_prefix = "MOCK_"
+                environment_override_warning_fields = {
+                    "warning_field1",
+                    "warning_field2",
+                }

From 07422ab9defaa7d191205b14a3c37f5f784c8514 Mon Sep 17 00:00:00 2001
From: GitHub -- tdilauro <tdilauro@users.noreply.github.com>
Date: Wed, 12 Jun 2024 09:14:20 -0400
Subject: [PATCH 4/8] Add tests.

---
 .../manager/api/admin/controller/test_view.py | 72 +++++++++++++++++
 tests/manager/service/test_configuration.py   | 78 +++++++++++++++++--
 2 files changed, 144 insertions(+), 6 deletions(-)

diff --git a/tests/manager/api/admin/controller/test_view.py b/tests/manager/api/admin/controller/test_view.py
index afdecbfc16..aba91bac75 100644
--- a/tests/manager/api/admin/controller/test_view.py
+++ b/tests/manager/api/admin/controller/test_view.py
@@ -1,11 +1,17 @@
 import re
+from unittest.mock import patch
 
 import flask
+import pytest
+from _pytest.logging import LogCaptureFixture
+from _pytest.monkeypatch import MonkeyPatch
 from werkzeug.http import dump_cookie
 
+from palace.manager.api.admin.config import AdminClientFeatureFlags
 from palace.manager.api.admin.password_admin_authentication_provider import (
     PasswordAdminAuthenticationProvider,
 )
+from palace.manager.service.logging.configuration import LogLevel
 from palace.manager.sqlalchemy.model.admin import AdminRole
 from palace.manager.sqlalchemy.model.library import Library
 from tests.fixtures.api_admin import AdminControllerFixture
@@ -163,3 +169,69 @@ def test_roles(self, admin_ctrl_fixture: AdminControllerFixture):
                 % admin_ctrl_fixture.ctrl.db.default_library().short_name
                 in html
             )
+
+    def test_feature_flags_defaults(
+        self,
+        admin_ctrl_fixture: AdminControllerFixture,
+        monkeypatch: pytest.MonkeyPatch,
+    ):
+        admin_ctrl_fixture.admin.password_hashed = None
+        html_feature_flags_re = re.compile(
+            r"featureFlags: {(.*)?}", re.MULTILINE | re.DOTALL
+        )
+
+        with admin_ctrl_fixture.ctrl.app.test_request_context("/admin"):
+            response = admin_ctrl_fixture.manager.admin_view_controller(None, None)
+            assert 200 == response.status_code
+            html = response.get_data(as_text=True)
+
+            match = html_feature_flags_re.search(html)
+            assert match is not None
+            feature_flags = match.groups(0)[0]
+            assert '"enableAutoList": true' in feature_flags
+            assert '"showCircEventsDownload": true' in feature_flags
+            assert '"reportsOnlyForSysadmins": true' in feature_flags
+
+    def test_feature_flags_overridden(
+        self,
+        admin_ctrl_fixture: AdminControllerFixture,
+        monkeypatch: MonkeyPatch,
+        caplog: LogCaptureFixture,
+    ):
+        caplog.set_level(LogLevel.warning)
+        admin_ctrl_fixture.admin.password_hashed = None
+        html_feature_flags_re = re.compile(
+            r"featureFlags: {(.*)?}", re.MULTILINE | re.DOTALL
+        )
+
+        monkeypatch.setenv("PALACE_ADMINUI_FEATURE_ENABLE_AUTO_LIST", "false")
+        monkeypatch.setenv("PALACE_ADMINUI_FEATURE_SHOW_CIRC_EVENTS_DOWNLOAD", "false")
+        monkeypatch.setenv("PALACE_ADMINUI_FEATURE_REPORTS_ONLY_FOR_SYSADMINS", "false")
+
+        with (
+            patch(
+                "palace.manager.api.admin.config.Configuration.admin_feature_flags"
+            ) as admin_feature_flags,
+            admin_ctrl_fixture.ctrl.app.test_request_context("/admin"),
+        ):
+            # Use fresh feature flags, instead of using a cached value.
+            admin_feature_flags.return_value = AdminClientFeatureFlags()
+            assert (
+                "Some `environment_override_warning_fields` are overridden in the environment. Please "
+                in caplog.text
+            )
+            assert "enable_auto_list" in caplog.text
+            assert "show_circ_events_download" in caplog.text
+            assert "reports_only_for_sysadmins" not in caplog.text
+
+            response = admin_ctrl_fixture.manager.admin_view_controller(None, None)
+            assert 200 == response.status_code
+            html = response.get_data(as_text=True)
+
+            match = html_feature_flags_re.search(html)
+            assert match is not None
+
+            feature_flags: str = match.groups(0)[0]  # type: ignore[assignment]
+            assert '"enableAutoList": true' in feature_flags
+            assert '"showCircEventsDownload": true' in feature_flags
+            assert '"reportsOnlyForSysadmins": false' in feature_flags
diff --git a/tests/manager/service/test_configuration.py b/tests/manager/service/test_configuration.py
index 068b610672..c6e02be149 100644
--- a/tests/manager/service/test_configuration.py
+++ b/tests/manager/service/test_configuration.py
@@ -7,6 +7,7 @@
 
 from palace.manager.core.config import CannotLoadConfiguration
 from palace.manager.service.configuration import ServiceConfiguration
+from palace.manager.service.logging.configuration import LogLevel
 from palace.manager.util.settings import ServiceConfigurationWithLimitedEnvOverride
 
 if TYPE_CHECKING:
@@ -29,13 +30,17 @@ def __init__(self, type: str, monkeypatch: MonkeyPatch, fs: FakeFilesystem):
         self.fs = fs
 
         # Make sure the environment is empty
-        self.monkeypatch.delenv("MOCK_STRING_WITHOUT_DEFAULT", raising=False)
-        self.monkeypatch.delenv("MOCK_INT_TYPE", raising=False)
-        self.monkeypatch.delenv("MOCK_STRING_WITH_DEFAULT", raising=False)
+        self.reset(
+            ["MOCK_STRING_WITHOUT_DEFAULT", "MOCK_INT_TYPE", "MOCK_STRING_WITH_DEFAULT"]
+        )
 
         # Make sure the .env file is empty
         self.env_file = fs.create_file(".env", contents="")
 
+    def reset(self, keys: list[str]):
+        for key in keys:
+            self.monkeypatch.delenv(key, raising=False)
+
     def set(self, key: str, value: str):
         if self.type == "env":
             self.set_env(key, value)
@@ -174,14 +179,75 @@ def test_environment_override_warning_fields(
         caplog: pytest.LogCaptureFixture,
         service_configuration_fixture: ServiceConfigurationFixture,
     ):
+        caplog.set_level(LogLevel.warning)
+
         class MockConfiguration(ServiceConfigurationWithLimitedEnvOverride):
-            field: bool = True
-            warning_field1: bool = True
+            field1: bool = True
             warning_field2: bool = True
 
             class Config:
                 env_prefix = "MOCK_"
                 environment_override_warning_fields = {
-                    "warning_field1",
                     "warning_field2",
                 }
+
+        service_configuration_fixture.reset(["MOCK_FIELD1", "MOCK_WARNING_FIELD2"])
+        config1 = MockConfiguration()
+
+        assert config1.field1 is True
+        assert config1.warning_field2 is True
+        assert (
+            "Some `environment_override_warning_fields` are overridden in the environment."
+            not in caplog.text
+        )
+        assert "warning_field2" not in caplog.text
+        assert "field1" not in caplog.text
+
+        service_configuration_fixture.set("MOCK_FIELD1", "false")
+        service_configuration_fixture.set("MOCK_WARNING_FIELD2", "false")
+        config2 = MockConfiguration()
+
+        assert config2.field1 is False
+        assert config2.warning_field2 is True
+        assert (
+            "Some `environment_override_warning_fields` are overridden in the environment."
+            in caplog.text
+        )
+        assert "warning_field2" in caplog.text
+        assert "field1" not in caplog.text
+
+        service_configuration_fixture.reset(["MOCK_FIELD1", "MOCK_WARNING_FIELD2"])
+
+    def test_environment_override_error_field(
+        self,
+        service_configuration_fixture: ServiceConfigurationFixture,
+    ):
+        class MockConfiguration(ServiceConfigurationWithLimitedEnvOverride):
+            field1: bool = True
+            error_field2: bool = True
+
+            class Config:
+                env_prefix = "MOCK_"
+                environment_override_error_fields = {
+                    "error_field2",
+                }
+
+        service_configuration_fixture.reset(["MOCK_FIELD1", "MOCK_ERROR_FIELD2"])
+        config1 = MockConfiguration()
+
+        assert config1.field1 is True
+        assert config1.error_field2 is True
+
+        service_configuration_fixture.set("MOCK_FIELD1", "false")
+        service_configuration_fixture.set("MOCK_ERROR_FIELD2", "false")
+        with pytest.raises(CannotLoadConfiguration) as exc_info:
+            MockConfiguration()
+
+        assert (
+            "Some `environment_override_error_fields` are overridden in the environment."
+            in str(exc_info.value)
+        )
+        assert "error_field2" in str(exc_info.value)
+        assert "field1" not in str(exc_info.value)
+
+        service_configuration_fixture.reset(["MOCK_FIELD1", "MOCK_ERROR_FIELD2"])

From 179766e309a0493eeeda9183a08729e34acb3385 Mon Sep 17 00:00:00 2001
From: Tim DiLauro <tdilauro@users.noreply.github.com>
Date: Wed, 12 Jun 2024 09:29:09 -0400
Subject: [PATCH 5/8] Appease mypy.

---
 tests/manager/api/admin/controller/test_view.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/manager/api/admin/controller/test_view.py b/tests/manager/api/admin/controller/test_view.py
index aba91bac75..1a5814e4d9 100644
--- a/tests/manager/api/admin/controller/test_view.py
+++ b/tests/manager/api/admin/controller/test_view.py
@@ -187,7 +187,7 @@ def test_feature_flags_defaults(
 
             match = html_feature_flags_re.search(html)
             assert match is not None
-            feature_flags = match.groups(0)[0]
+            feature_flags: str = match.groups(0)[0]  # type: ignore[assignment]
             assert '"enableAutoList": true' in feature_flags
             assert '"showCircEventsDownload": true' in feature_flags
             assert '"reportsOnlyForSysadmins": true' in feature_flags

From 13a21c4544a3dd44e006d2a0c293b4ec71f3d556 Mon Sep 17 00:00:00 2001
From: Tim DiLauro <tdilauro@users.noreply.github.com>
Date: Wed, 12 Jun 2024 10:51:59 -0400
Subject: [PATCH 6/8] Review feedback: remove commented code.

---
 src/palace/manager/api/admin/controller/view.py | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/src/palace/manager/api/admin/controller/view.py b/src/palace/manager/api/admin/controller/view.py
index ab6a819b59..54c1de8be6 100644
--- a/src/palace/manager/api/admin/controller/view.py
+++ b/src/palace/manager/api/admin/controller/view.py
@@ -67,9 +67,6 @@ def __call__(self, collection, book, path=None):
         admin_js = AdminClientConfig.lookup_asset_url(key="admin_js")
         admin_css = AdminClientConfig.lookup_asset_url(key="admin_css")
 
-        # # We always have local_analytics
-        # show_circ_events_download = True
-
         response = Response(
             flask.render_template_string(
                 admin_template,

From 4b9c2726ede2aa348c6e0a8d79b477d2fbc24e41 Mon Sep 17 00:00:00 2001
From: Tim DiLauro <tdilauro@users.noreply.github.com>
Date: Wed, 12 Jun 2024 10:50:32 -0400
Subject: [PATCH 7/8] Review feedback: put new settings class with parent.

---
 src/palace/manager/api/admin/config.py                    | 4 +++-
 src/palace/manager/service/analytics/configuration.py     | 4 +++-
 src/palace/manager/service/celery/configuration.py        | 4 +++-
 src/palace/manager/service/configuration/__init__.py      | 1 +
 .../configuration/limited_env_override.py}                | 4 +++-
 .../service_configuration.py}                             | 0
 src/palace/manager/service/email/configuration.py         | 4 +++-
 src/palace/manager/service/fcm/configuration.py           | 4 +++-
 src/palace/manager/service/logging/configuration.py       | 4 +++-
 src/palace/manager/service/search/configuration.py        | 4 +++-
 src/palace/manager/service/sitewide.py                    | 4 +++-
 src/palace/manager/service/storage/configuration.py       | 4 +++-
 tests/fixtures/config.py                                  | 4 +++-
 tests/manager/service/storage/test_s3.py                  | 4 +++-
 tests/manager/service/test_configuration.py               | 8 ++++++--
 15 files changed, 43 insertions(+), 14 deletions(-)
 create mode 100644 src/palace/manager/service/configuration/__init__.py
 rename src/palace/manager/{util/settings.py => service/configuration/limited_env_override.py} (98%)
 rename src/palace/manager/service/{configuration.py => configuration/service_configuration.py} (100%)

diff --git a/src/palace/manager/api/admin/config.py b/src/palace/manager/api/admin/config.py
index 570a4ea3fe..3ac5c1296d 100644
--- a/src/palace/manager/api/admin/config.py
+++ b/src/palace/manager/api/admin/config.py
@@ -5,10 +5,12 @@
 from pydantic import Field
 from requests import RequestException
 
+from palace.manager.service.configuration.limited_env_override import (
+    ServiceConfigurationWithLimitedEnvOverride,
+)
 from palace.manager.util.flask_util import _snake_to_camel_case
 from palace.manager.util.http import HTTP, RequestNetworkException
 from palace.manager.util.log import LoggerMixin
-from palace.manager.util.settings import ServiceConfigurationWithLimitedEnvOverride
 
 
 class AdminClientFeatureFlags(ServiceConfigurationWithLimitedEnvOverride):
diff --git a/src/palace/manager/service/analytics/configuration.py b/src/palace/manager/service/analytics/configuration.py
index ef3e87500d..56895b5bd0 100644
--- a/src/palace/manager/service/analytics/configuration.py
+++ b/src/palace/manager/service/analytics/configuration.py
@@ -1,4 +1,6 @@
-from palace.manager.service.configuration import ServiceConfiguration
+from palace.manager.service.configuration.service_configuration import (
+    ServiceConfiguration,
+)
 
 
 class AnalyticsConfiguration(ServiceConfiguration):
diff --git a/src/palace/manager/service/celery/configuration.py b/src/palace/manager/service/celery/configuration.py
index ebe531e1cb..fe686d5bd8 100644
--- a/src/palace/manager/service/celery/configuration.py
+++ b/src/palace/manager/service/celery/configuration.py
@@ -2,7 +2,9 @@
 
 from pydantic import RedisDsn
 
-from palace.manager.service.configuration import ServiceConfiguration
+from palace.manager.service.configuration.service_configuration import (
+    ServiceConfiguration,
+)
 
 
 class CeleryConfiguration(ServiceConfiguration):
diff --git a/src/palace/manager/service/configuration/__init__.py b/src/palace/manager/service/configuration/__init__.py
new file mode 100644
index 0000000000..9d48db4f9f
--- /dev/null
+++ b/src/palace/manager/service/configuration/__init__.py
@@ -0,0 +1 @@
+from __future__ import annotations
diff --git a/src/palace/manager/util/settings.py b/src/palace/manager/service/configuration/limited_env_override.py
similarity index 98%
rename from src/palace/manager/util/settings.py
rename to src/palace/manager/service/configuration/limited_env_override.py
index 31a9eac63c..1dc7f87948 100644
--- a/src/palace/manager/util/settings.py
+++ b/src/palace/manager/service/configuration/limited_env_override.py
@@ -6,7 +6,9 @@
 from pydantic.fields import ModelField
 
 from palace.manager.core.config import CannotLoadConfiguration
-from palace.manager.service.configuration import ServiceConfiguration
+from palace.manager.service.configuration.service_configuration import (
+    ServiceConfiguration,
+)
 from palace.manager.util.log import LoggerMixin
 
 
diff --git a/src/palace/manager/service/configuration.py b/src/palace/manager/service/configuration/service_configuration.py
similarity index 100%
rename from src/palace/manager/service/configuration.py
rename to src/palace/manager/service/configuration/service_configuration.py
diff --git a/src/palace/manager/service/email/configuration.py b/src/palace/manager/service/email/configuration.py
index 5f160f9b0c..cfe2800df3 100644
--- a/src/palace/manager/service/email/configuration.py
+++ b/src/palace/manager/service/email/configuration.py
@@ -1,6 +1,8 @@
 from pydantic import EmailStr, PositiveInt
 
-from palace.manager.service.configuration import ServiceConfiguration
+from palace.manager.service.configuration.service_configuration import (
+    ServiceConfiguration,
+)
 
 
 class EmailConfiguration(ServiceConfiguration):
diff --git a/src/palace/manager/service/fcm/configuration.py b/src/palace/manager/service/fcm/configuration.py
index d2b722408f..bf5309ca41 100644
--- a/src/palace/manager/service/fcm/configuration.py
+++ b/src/palace/manager/service/fcm/configuration.py
@@ -1,6 +1,8 @@
 from pathlib import Path
 
-from palace.manager.service.configuration import ServiceConfiguration
+from palace.manager.service.configuration.service_configuration import (
+    ServiceConfiguration,
+)
 
 
 class FcmConfiguration(ServiceConfiguration):
diff --git a/src/palace/manager/service/logging/configuration.py b/src/palace/manager/service/logging/configuration.py
index e47d199f5d..5c8b5c6502 100644
--- a/src/palace/manager/service/logging/configuration.py
+++ b/src/palace/manager/service/logging/configuration.py
@@ -9,7 +9,9 @@
 from pydantic import PositiveInt, validator
 from watchtower import DEFAULT_LOG_STREAM_NAME
 
-from palace.manager.service.configuration import ServiceConfiguration
+from palace.manager.service.configuration.service_configuration import (
+    ServiceConfiguration,
+)
 
 # TODO: Remove this when we drop support for Python 3.10
 if sys.version_info >= (3, 11):
diff --git a/src/palace/manager/service/search/configuration.py b/src/palace/manager/service/search/configuration.py
index e953259f55..d9c9b6b8d5 100644
--- a/src/palace/manager/service/search/configuration.py
+++ b/src/palace/manager/service/search/configuration.py
@@ -1,6 +1,8 @@
 from pydantic import AnyHttpUrl
 
-from palace.manager.service.configuration import ServiceConfiguration
+from palace.manager.service.configuration.service_configuration import (
+    ServiceConfiguration,
+)
 
 
 class SearchConfiguration(ServiceConfiguration):
diff --git a/src/palace/manager/service/sitewide.py b/src/palace/manager/service/sitewide.py
index 771866097c..3fad5d7328 100644
--- a/src/palace/manager/service/sitewide.py
+++ b/src/palace/manager/service/sitewide.py
@@ -4,7 +4,9 @@
 
 from pydantic import AnyHttpUrl, NonNegativeInt, validator
 
-from palace.manager.service.configuration import ServiceConfiguration
+from palace.manager.service.configuration.service_configuration import (
+    ServiceConfiguration,
+)
 
 
 class SitewideConfiguration(ServiceConfiguration):
diff --git a/src/palace/manager/service/storage/configuration.py b/src/palace/manager/service/storage/configuration.py
index bf736cc6d6..bc4334200e 100644
--- a/src/palace/manager/service/storage/configuration.py
+++ b/src/palace/manager/service/storage/configuration.py
@@ -1,7 +1,9 @@
 import boto3
 from pydantic import AnyHttpUrl, parse_obj_as, validator
 
-from palace.manager.service.configuration import ServiceConfiguration
+from palace.manager.service.configuration.service_configuration import (
+    ServiceConfiguration,
+)
 
 
 class StorageConfiguration(ServiceConfiguration):
diff --git a/tests/fixtures/config.py b/tests/fixtures/config.py
index b2d1518aee..e45bb2a93c 100644
--- a/tests/fixtures/config.py
+++ b/tests/fixtures/config.py
@@ -6,7 +6,9 @@
 from pydantic import AnyUrl, Extra
 from typing_extensions import Self
 
-from palace.manager.service.configuration import ServiceConfiguration
+from palace.manager.service.configuration.service_configuration import (
+    ServiceConfiguration,
+)
 
 
 @dataclasses.dataclass
diff --git a/tests/manager/service/storage/test_s3.py b/tests/manager/service/storage/test_s3.py
index 6ac9fe00de..8e4ac42f07 100644
--- a/tests/manager/service/storage/test_s3.py
+++ b/tests/manager/service/storage/test_s3.py
@@ -12,7 +12,9 @@
 from pydantic import AnyHttpUrl
 
 from palace.manager.core.config import CannotLoadConfiguration
-from palace.manager.service.configuration import ServiceConfiguration
+from palace.manager.service.configuration.service_configuration import (
+    ServiceConfiguration,
+)
 from palace.manager.service.storage.container import Storage
 from palace.manager.service.storage.s3 import S3Service
 from tests.fixtures.config import FixtureTestUrlConfiguration
diff --git a/tests/manager/service/test_configuration.py b/tests/manager/service/test_configuration.py
index c6e02be149..21b08aab16 100644
--- a/tests/manager/service/test_configuration.py
+++ b/tests/manager/service/test_configuration.py
@@ -6,9 +6,13 @@
 from pyfakefs.fake_filesystem import FakeFilesystem
 
 from palace.manager.core.config import CannotLoadConfiguration
-from palace.manager.service.configuration import ServiceConfiguration
+from palace.manager.service.configuration.limited_env_override import (
+    ServiceConfigurationWithLimitedEnvOverride,
+)
+from palace.manager.service.configuration.service_configuration import (
+    ServiceConfiguration,
+)
 from palace.manager.service.logging.configuration import LogLevel
-from palace.manager.util.settings import ServiceConfigurationWithLimitedEnvOverride
 
 if TYPE_CHECKING:
     from pytest import MonkeyPatch

From 6626f10cd83a1c086600240d44bc1cbe153bf1ca Mon Sep 17 00:00:00 2001
From: Tim DiLauro <tdilauro@users.noreply.github.com>
Date: Wed, 12 Jun 2024 11:45:13 -0400
Subject: [PATCH 8/8] Fix some more types.

---
 .../service/configuration/limited_env_override.py   | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/src/palace/manager/service/configuration/limited_env_override.py b/src/palace/manager/service/configuration/limited_env_override.py
index 1dc7f87948..c85fe7644f 100644
--- a/src/palace/manager/service/configuration/limited_env_override.py
+++ b/src/palace/manager/service/configuration/limited_env_override.py
@@ -1,5 +1,4 @@
 import functools
-from collections.abc import Callable
 from typing import Any
 
 from pydantic.env_settings import BaseSettings, SettingsSourceCallable
@@ -35,9 +34,9 @@ class Config:
         @classmethod
         def customise_sources(
             cls,
-            init_settings,
-            env_settings,
-            file_secret_settings,
+            init_settings: SettingsSourceCallable,
+            env_settings: SettingsSourceCallable,
+            file_secret_settings: SettingsSourceCallable,
         ) -> tuple[SettingsSourceCallable, ...]:
             # We have to wrap the environment settings source in our own function
             # so that we can report on/strip out fields that are not overridable
@@ -49,13 +48,13 @@ def customise_sources(
             )
 
 
-def _env_var_for(field: ModelField) -> str | None:
-    env_prefix = field.model_config.env_prefix  # type: ignore[attr-defined]
+def _env_var_for(field: ModelField) -> str:
+    env_prefix = field.model_config.env_prefix or ""  # type: ignore[attr-defined]
     return (env_prefix + field.name).upper()
 
 
 def _restrict_environment(
-    env_settings: Callable[[BaseSettings], dict[str, Any]], settings: BaseSettings
+    env_settings: SettingsSourceCallable, settings: BaseSettings
 ) -> dict[str, Any]:
     """Limit environment variables to those not restricted by the `environment_override_*` settings.