Configure Tower in Tower:

* Add separate Django app for configuration: awx.conf.
* Migrate from existing main.TowerSettings model to conf.Setting.
* Add settings wrapper to allow get/set/del via django.conf.settings.
* Update existing references to tower_settings to use django.conf.settings.
* Add a settings registry to allow for each Django app to register configurable settings.
* Support setting validation and conversion using Django REST Framework fields.
* Add /api/v1/settings/ to display a list of setting categories.
* Add /api/v1/settings/<slug>/ to display all settings in a category as a single object.
* Allow PUT/PATCH to update setting singleton, DELETE to reset to defaults.
* Add "all" category to display all settings across categories.
* Add "changed" category to display only settings configured in the database.
* Support per-user settings via "user" category (/api/v1/settings/user/).
* Support defaults for user settings via "user-defaults" category (/api/v1/settings/user-defaults/).
* Update serializer metadata to support category, category_slug and placeholder on OPTIONS responses.
* Update serializer metadata to handle child fields of a list/dict.
* Hide raw data form in browsable API for OPTIONS and DELETE.
* Combine existing licensing code into single "TaskEnhancer" class.
* Move license helper functions from awx.api.license into awx.conf.license.
* Update /api/v1/config/ to read/verify/update license using TaskEnhancer and settings wrapper.
* Add support for caching settings accessed via settings wrapper.
* Invalidate cached settings when Setting model changes or is deleted.
* Preload all database settings into cache on first access via settings wrapper.
* Add support for read-only settings than can update their value depending on other settings.
* Use setting_changed signal whenever a setting changes.
* Register configurable authentication, jobs, system and ui settings.
* Register configurable LDAP, RADIUS and social auth settings.
* Add custom fields and validators for URL, LDAP, RADIUS and social auth settings.
* Rewrite existing validator for Credential ssh_private_key to support validating private keys, certs or combinations of both.
* Get all unit/functional tests working with above changes.
* Add "migrate_to_database_settings" command to determine settings to be migrated into the database and comment them out when set in Python settings files.
* Add support for migrating license key from file to database.
* Remove database-configuable settings from local_settings.py example files.
* Update setup role to no longer install files for database-configurable settings.

f 94ff6ee More settings work.
f af4c4e0 Even more db settings stuff.
f 96ea9c0 More settings, attempt at singleton serializer for settings.
f 937c760 More work on singleton/category views in API, add code to comment out settings in Python files, work on command to migrate settings to database.
f 425b0d3 Minor fixes for sprint demo.
f ea402a4 Add support for read-only settings, cleanup license engine, get license support working with DB settings.
f ec289e4 Rename migration, minor fixmes, update setup role.
f 603640b Rewrite key/cert validator, finish adding social auth fields, hook up signals for setting_changed, use None to imply a setting is not set.
f 67d1b5a Get functional/unit tests passing.
f 2919b62 Flake8 fixes.
f e62f421 Add redbaron to requirements, get file to database migration working (except for license).
f c564508 Add support for migrating license file.
f 982f767 Add support for regex in social map fields.

awx/conf/views.py

@@ -0,0 +1,129 @@
+# Copyright (c) 2016 Ansible, Inc.
+# All Rights Reserved.
+
+# Python
+import collections
+import json
+import sys
+
+# Django
+from django.core.urlresolvers import reverse
+from django.http import Http404
+from django.utils.translation import ugettext_lazy as _
+
+# Django REST Framework
+from rest_framework.exceptions import PermissionDenied
+from rest_framework.response import Response
+from rest_framework import serializers
+from rest_framework import status
+
+# Tower
+from awx.api.generics import *  # noqa
+from awx.main.utils import *  # noqa
+from awx.conf.models import Setting
+from awx.conf.serializers import SettingCategorySerializer, SettingSingletonSerializer
+from awx.conf import settings_registry
+
+
+SettingCategory = collections.namedtuple('SettingCategory', ('url', 'slug', 'name'))
+
+
+class SettingCategoryList(ListAPIView):
+
+    model = Setting  # Not exactly, but needed for the view.
+    serializer_class = SettingCategorySerializer
+    filter_backends = []
+    new_in_310 = True
+    view_name = _('Setting Categories')
+
+    def get_queryset(self):
+        setting_categories = []
+        if self.request.user.is_superuser or self.request.user.is_system_auditor:
+            categories = settings_registry.get_registered_categories()
+        else:
+            categories = {'user': _('User')}
+        for category_slug in sorted(categories.keys()):
+            url = reverse('api:setting_singleton_detail', args=(category_slug,))
+            setting_categories.append(SettingCategory(url, category_slug, categories[category_slug]))
+        return setting_categories
+
+
+class SettingSingletonDetail(RetrieveUpdateDestroyAPIView):
+
+    model = Setting  # Not exactly, but needed for the view.
+    serializer_class = SettingSingletonSerializer
+    filter_backends = []
+    new_in_310 = True
+    view_name = _('Setting Detail')
+
+    def get_queryset(self):
+        self.category_slug = self.kwargs.get('category_slug', 'all')
+        all_category_slugs = settings_registry.get_registered_categories().keys()
+        if self.request.user.is_superuser or getattr(self.request.user, 'is_system_auditor', False):
+            category_slugs = all_category_slugs
+        else:
+            category_slugs = {'user'}
+        if self.category_slug not in all_category_slugs:
+            raise Http404
+        if self.category_slug not in category_slugs:
+            raise PermissionDenied()
+
+        registered_settings = settings_registry.get_registered_settings(category_slug=self.category_slug)
+        if self.category_slug == 'user':
+            return Setting.objects.filter(key__in=registered_settings, user=self.request.user)
+        else:
+            return Setting.objects.filter(key__in=registered_settings, user__isnull=True)
+
+    def get_object(self):
+        settings_qs = self.get_queryset()
+        registered_settings = settings_registry.get_registered_settings(category_slug=self.category_slug)
+        all_settings = {}
+        for setting in settings_qs:
+            all_settings[setting.key] = setting.value
+        for key in registered_settings:
+            if key in all_settings or self.category_slug == 'changed':
+                continue
+            try:
+                field = settings_registry.get_setting_field(key, for_user=bool(self.category_slug == 'user'))
+                all_settings[key] = field.get_default()
+            except serializers.SkipField:
+                all_settings[key] = None
+        all_settings['user'] = self.request.user if self.category_slug == 'user' else None
+        obj = type('Settings', (object,), all_settings)()
+        self.check_object_permissions(self.request, obj)
+        return obj
+
+    def perform_update(self, serializer):
+        settings_qs = self.get_queryset()
+        user = self.request.user if self.category_slug == 'user' else None
+        for key, value in serializer.validated_data.items():
+            setattr(serializer.instance, key, value)
+            # Always encode "raw" strings as JSON.
+            if isinstance(value, basestring):
+                value = json.dumps(value)
+            setting = settings_qs.filter(key=key).order_by('pk').first()
+            if not setting:
+                setting = Setting.objects.create(key=key, user=user, value=value)
+            elif setting.value != value or type(setting.value) != type(value):
+                setting.value = value
+                setting.save(update_fields=['value'])
+
+    def destroy(self, request, *args, **kwargs):
+        instance = self.get_object()
+        self.perform_destroy(instance)
+        return Response(status=status.HTTP_204_NO_CONTENT)
+
+    def perform_destroy(self, instance):
+        for setting in self.get_queryset():
+            setting.delete()
+
+
+# Create view functions for all of the class-based views to simplify inclusion
+# in URL patterns and reverse URL lookups, converting CamelCase names to
+# lowercase_with_underscore (e.g. MyView.as_view() becomes my_view).
+this_module = sys.modules[__name__]
+for attr, value in locals().items():
+    if isinstance(value, type) and issubclass(value, APIView):
+        name = camelcase_to_underscore(attr)
+        view = value.as_view()
+        setattr(this_module, name, view)