Transform dynamic settings logic to validation

Author: AlanCoding

ansible_base/lib/dynamic_config/constants.py

@@ -0,0 +1,36 @@
+from types import SimpleNamespace
+
+rest_filters = SimpleNamespace(
+    reserved_names=(
+        'page',
+        'page_size',
+        'format',
+        'order',
+        'order_by',
+        'search',
+        'type',
+        'host_filter',
+        'count_disabled',
+        'no_truncate',
+        'limit',
+        'validate',
+    ),
+    dab_rest_filters=(
+        'ansible_base.rest_filters.rest_framework.type_filter_backend.TypeFilterBackend',
+        'ansible_base.rest_filters.rest_framework.field_lookup_backend.FieldLookupBackend',
+        'rest_framework.filters.SearchFilter',
+        'ansible_base.rest_filters.rest_framework.order_backend.OrderByBackend',
+    ),
+)
+
+
+api_documentation = SimpleNamespace(
+    auto_schema='drf_spectacular.openapi.AutoSchema',
+    dab_spectacular_settings={
+        'TITLE': 'Open API',
+        'DESCRIPTION': 'Open API',
+        'VERSION': 'v1',
+        'SCHEMA_PATH_PREFIX': '/api/v1/',
+        'COMPONENT_NO_READ_ONLY_REQUIRED': True,
+    },
+)

ansible_base/lib/dynamic_config/dynaconf_helpers.py

@@ -16,14 +16,16 @@
 from dynaconf.utils.files import glob
 from dynaconf.utils.functional import empty
 
-from ansible_base.lib.dynamic_config.settings_logic import get_mergeable_dab_settings
+from .settings_logic import get_mergeable_dab_settings
+from .validators import dab_validators
 
 
 def factory(
     module_name: str,  # name of the module that calls this function
     app_name: str,  # main app name to be used to name env_switcher and envvar_prefix
     *,
     add_dab_settings: bool = True,  # add DAB settings to the settings object
+    add_dab_validators: bool = True,  # add DAB validators
     validators: list[Validator] | None = None,  # custom validators to be used in Dynaconf
     extra_envvar_prefixes: list[str] | None = None,  # extra prefixes to be used in envvar loader
     **options,  # options to be passed to Dynaconf
@@ -125,7 +127,11 @@ def factory(
     if validators:
         settings.validators.register(*validators)
 
-    add_dab_settings and load_dab_settings(settings)
+    if add_dab_settings:
+        load_dab_settings(settings)
+
+    if add_dab_validators:
+        load_dab_validators(settings)
 
     # Dynaconf allows composed modes
     # so current_env can be a comma separated string of modes (e.g. "development,quiet")
@@ -176,6 +182,14 @@ def load_dab_settings(settings: Dynaconf):
     settings.update(dab_settings, loader_identifier="load_dab_settings")
 
 
+def load_dab_validators(settings: Dynaconf):
+    """Add DAB settings validators to the dynaconf settings object."""
+    installed_apps = settings.get("INSTALLED_APPS")
+    for app_path, app_validators in dab_validators.items():
+        if app_path in installed_apps:
+            settings.validators.register(*app_validators)
+
+
 def load_standard_settings_files(settings: Dynaconf):
     """Load the standard settings files for Ansible Automation Platform.
 

ansible_base/lib/dynamic_config/settings_logic.py

@@ -3,6 +3,8 @@
 
 from ansible_base.lib.cache.fallback_cache import FALLBACK_CACHE, PRIMARY_CACHE
 
+from .constants import api_documentation, rest_filters
+
 #
 # If you are adding a new dynamic setting:
 #     Please be sure to modify pyproject.toml with your new settings in tool.setuptools.dynamic
@@ -11,13 +13,6 @@
 
 
 DEFAULT_AUTH_GROUP = 'auth.Group'
-DEFAULT_SPECTACULAR_SETTINGS = {
-    'TITLE': 'Open API',
-    'DESCRIPTION': 'Open API',
-    'VERSION': 'v1',
-    'SCHEMA_PATH_PREFIX': '/api/v1/',
-    'COMPONENT_NO_READ_ONLY_REQUIRED': True,
-}
 DEFAULT_ANSIBLE_BASE_AUTH = "ansible_base.authentication.backend.AnsibleBaseAuth"
 DEFAULT_ANSIBLE_BASE_JWT_CONSUMER_APP_NAME = "ansible_base.jwt_consumer"
 DEFAULT_ANSIBLE_BASE_RBAC_APP_NAME = "ansible_base.rbac"
@@ -92,51 +87,22 @@ def get_mergeable_dab_settings(settings: dict) -> dict:  # NOSONAR
     # without enabling the ansible_base.rest_filters app explicitly
     # we also apply this to views from other apps so we should always define it
     if settings.get('ANSIBLE_BASE_REST_FILTERS_RESERVED_NAMES') is None:
-        dab_data['ANSIBLE_BASE_REST_FILTERS_RESERVED_NAMES'] = (
-            'page',
-            'page_size',
-            'format',
-            'order',
-            'order_by',
-            'search',
-            'type',
-            'host_filter',
-            'count_disabled',
-            'no_truncate',
-            'limit',
-            'validate',
-        )
+        dab_data['ANSIBLE_BASE_REST_FILTERS_RESERVED_NAMES'] = rest_filters.reserved_names
 
     # SPECTACULAR SETTINGS
-    if 'ansible_base.api_documentation' in installed_apps:
-        rest_framework.setdefault('DEFAULT_SCHEMA_CLASS', 'drf_spectacular.openapi.AutoSchema')
-
-        if 'drf_spectacular' not in installed_apps:
-            installed_apps.append('drf_spectacular')
-
-        for key, value in DEFAULT_SPECTACULAR_SETTINGS.items():
-            if key not in spectacular_settings:
-                spectacular_settings[key] = value
+    # NOTE: validators check default schema class and that drf_spectacular is installed
 
     # General, factual, constant of all filters that ansible_base.rest_filters ships
-    dab_data['ANSIBLE_BASE_ALL_REST_FILTERS'] = (
-        'ansible_base.rest_filters.rest_framework.type_filter_backend.TypeFilterBackend',
-        'ansible_base.rest_filters.rest_framework.field_lookup_backend.FieldLookupBackend',
-        'rest_framework.filters.SearchFilter',
-        'ansible_base.rest_filters.rest_framework.order_backend.OrderByBackend',
-    )
-    if 'ansible_base.rest_filters' in installed_apps:
-        rest_framework['DEFAULT_FILTER_BACKENDS'] = dab_data['ANSIBLE_BASE_ALL_REST_FILTERS']
-    else:
+    dab_data['ANSIBLE_BASE_ALL_REST_FILTERS'] = rest_filters.dab_rest_filters
+    if 'ansible_base.rest_filters' not in installed_apps:
         # Explanation - these are the filters for views provided by DAB like /authenticators/
         # we want them to be enabled by default _even if_ the rest_filters app is not used
         # so that clients have consistency, but if an app wants to turn them off, they can.
         # these will be combined with the actual DRF defaults in our base view
         dab_data['ANSIBLE_BASE_CUSTOM_VIEW_FILTERS'] = dab_data['ANSIBLE_BASE_ALL_REST_FILTERS']
 
     if 'ansible_base.authentication' in installed_apps:
-        if 'social_django' not in installed_apps:
-            installed_apps.append('social_django')
+        # TODO: stop point for migrating modifications to validations
         if DEFAULT_ANSIBLE_BASE_AUTH not in authentication_backends:
             authentication_backends.append(DEFAULT_ANSIBLE_BASE_AUTH)
 

ansible_base/lib/dynamic_config/validators.py

@@ -0,0 +1,52 @@
+from dynaconf import Validator
+
+from .constants import api_documentation, rest_filters
+
+
+def has_spectacular(v):
+    return bool('drf_spectacular' in v)
+
+
+def has_drf_spectacular_settings(v):
+    if 'DEFAULT_SCHEMA_CLASS' not in v:
+        return False
+    if v['DEFAULT_SCHEMA_CLASS'] != api_documentation.auto_schema:
+        return False
+
+    spectacular_settings = v['SPECTACULAR_SETTINGS']
+    for key, value in api_documentation.dab_spectacular_settings.items():
+        user_value = spectacular_settings.get(key)
+        if user_value != value:
+            return False
+    return True
+
+
+def has_all_rest_filters(v):
+    user_filters = v.get('DEFAULT_FILTER_BACKENDS', [])
+    for cls_name in rest_filters.dab_rest_filters:
+        if cls_name not in user_filters:
+            return False
+    return True
+
+
+def has_social_django(v):
+    return bool('social_django' in v)
+
+
+dab_validators = {
+    "ansible_base.api_documentation": [
+        Validator("INSTALLED_APPS", condition=has_spectacular),
+        Validator("REST_FRAMEWORK", condition=has_drf_spectacular_settings),
+    ],
+    "ansible_base.rest_filters": [
+        Validator(
+            "REST_FRAMEWORK",
+            condition=has_all_rest_filters,
+            messages={
+                "condition": "{name} lacks required rest_filters entries in DEFAULT_FILTER_BACKENDS value=({value}) in env {env}, required: "
+                + str(rest_filters.dab_rest_filters)
+            },
+        )
+    ],
+    "ansible_base.authentication": [Validator("INSTALLED_APPS", condition=has_social_django)],
+}

docs/apps/api_documentation.md

@@ -4,47 +4,31 @@ django-ansible-base uses django-spectacular to auto-generate both Open API and S
 
 ## Settings
 
-Add `ansible_base.api_documentation` to your installed apps:
+Add `ansible_base.api_documentation` to your installed apps.
+Plus do what we tell you here.
 
 ```
-INSTALLED_APPS = [
-    ...
-    'ansible_base.api_documentation',
-]
-```
+from ansible_base.lib.dynamic_config.constants import api_documentation
 
-### Additional Settings
-Additional settings are required to enable api_documentation.
-This will happen automatically if using [dynamic_settings](../Installation.md)
 
-First, you need to add `drf_spectacular` to your `INSTALLED_APPS`:
-```
 INSTALLED_APPS = [
     ...
+    'ansible_base.api_documentation',
     'drf_spectacular',
-    ...
 ]
-```
-
-Additionally, we create a `SPECTACULAR_SETTINGS` entry if its not already present:
-```
-SPECTACULAR_SETTINGS = {
-    'TITLE': 'Open API',
-    'DESCRIPTION': 'Open API',
-    'VERSION': 'v1',
-    'SCHEMA_PATH_PREFIX': '/api/v1/',
-}
-```
 
-Finally, add a `DEFAULT_SCHEMA_CLASS` to your `REST_FRAMEWORK` setting:
-```
 REST_FRAMEWORK = {
     ...
-    'DEFAULT_SCHEMA_CLASS': 'drf_spectacular.openapi.AutoSchema',
+    'SPECTACULAR_SETTINGS': api_documentation.dab_spectacular_settings,
+    'DEFAULT_SCHEMA_CLASS': api_documentation.auto_schema,
     ...
 }
 ```
 
+If you do not set these, our validators will let you know by throwing an error.
+See [dynamic_settings](../Installation.md) for more information.
+
+
 ## URLS
 
 This feature includes URLs which you will get if you are using [dynamic urls](../..//Installation.md)

docs/apps/rest_filters.md

@@ -7,30 +7,24 @@ django-ansible-base has a built in mechanism for filtering and sorting query set
 Add `ansible_base.rest_filters` to your installed apps:
 
 ```
+from ansible_base.lib.dynamic_config.constants import rest_filters
+
+
 INSTALLED_APPS = [
     ...
     'ansible_base.rest_filters',
 ]
-```
 
-### Additional Settings
-Additional settings are required to enable filtering on your rest endpoints.
-This will happen automatically if using [dynamic_settings](../Installation.md)
-
-To manually enable filtering without dynamic settings the following items need to be included in your settings:
-```
 REST_FRAMEWORK = {
     ...
-    'DEFAULT_FILTER_BACKENDS': (
-        'ansible_base.rest_filters.rest_framework.type_filter_backend.TypeFilterBackend',
-        'ansible_base.rest_filters.rest_framework.field_lookup_backend.FieldLookupBackend',
-        'rest_framework.filters.SearchFilter',
-        'ansible_base.rest_filters.rest_framework.order_backend.OrderByBackend',
-    ),
+    'DEFAULT_FILTER_BACKENDS': rest_filters.dab_rest_filters,
     ...
 }
 ```
 
+If you do not follow these instructions, the system will throw a validation error.
+Read more in [dynamic_settings](../Installation.md).
+
 ## Letting Extra Query Params Through
 
 Sometimes you may have a view that needs to use a query param for a reason unrelated to filtering.

test_app/defaults.py

@@ -4,6 +4,8 @@
 
 import os
 
+from ansible_base.lib.dynamic_config.constants import api_documentation, rest_filters
+
 BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
 DEBUG = True
 ALLOWED_HOSTS = ["*"]
@@ -52,6 +54,7 @@
     'django.contrib.staticfiles',
     'rest_framework',
     'social_django',
+    'drf_spectacular',
     'ansible_base.api_documentation',
     'ansible_base.authentication',
     'ansible_base.rest_filters',
@@ -98,6 +101,9 @@
         'ansible_base.oauth2_provider.permissions.OAuth2ScopePermission',
         'ansible_base.rbac.api.permissions.AnsibleBaseObjectPermissions',
     ],
+    'SPECTACULAR_SETTINGS': api_documentation.dab_spectacular_settings,
+    'DEFAULT_SCHEMA_CLASS': api_documentation.auto_schema,
+    'DEFAULT_FILTER_BACKENDS': rest_filters.dab_rest_filters,
 }
 
 DATABASES = {