authn: Only lookup settings from DB if they are really used.

When computing the form defaults only query the DB if we
need the value from DB.

rhodecode/authentication/views.py

@@ -1,190 +1,190 b''
 # -*- coding: utf-8 -*-
 
 # Copyright (C) 2012-2016  RhodeCode GmbH
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU Affero General Public License, version 3
 # (only), as published by the Free Software Foundation.
 #
 # This program is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 # GNU General Public License for more details.
 #
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #
 # This program is dual-licensed. If you wish to learn more about the
 # RhodeCode Enterprise Edition, including its added features, Support services,
 # and proprietary license terms, please see https://rhodecode.com/licenses/
 
 import colander
 import formencode.htmlfill
 import logging
 
 from pyramid.httpexceptions import HTTPFound
 from pyramid.renderers import render
 from pyramid.response import Response
 
 from rhodecode.authentication.base import get_auth_cache_manager
 from rhodecode.authentication.interface import IAuthnPluginRegistry
 from rhodecode.lib import auth
 from rhodecode.lib.auth import LoginRequired, HasPermissionAllDecorator
 from rhodecode.model.forms import AuthSettingsForm
 from rhodecode.model.meta import Session
 from rhodecode.model.settings import SettingsModel
 from rhodecode.translation import _
 
 log = logging.getLogger(__name__)
 
 
 class AuthnPluginViewBase(object):
 
     def __init__(self, context, request):
         self.request = request
         self.context = context
         self.plugin = context.plugin
         self._rhodecode_user = request.user
 
     @LoginRequired()
     @HasPermissionAllDecorator('hg.admin')
     def settings_get(self, defaults=None, errors=None):
         """
         View that displays the plugin settings as a form.
         """
         defaults = defaults or {}
         errors = errors or {}
         schema = self.plugin.get_settings_schema()
 
         # Compute default values for the form. Priority is:
         # 1. Passed to this method 2. DB value 3. Schema default
         for node in schema:
-            value = self.plugin.get_setting_by_name(
+            if node.name not in defaults:
+                defaults[node.name] = self.plugin.get_setting_by_name(
                 node.name, node.default)
-            defaults.setdefault(node.name, value)
 
         template_context = {
             'defaults': defaults,
             'errors': errors,
             'plugin': self.context.plugin,
             'resource': self.context,
         }
 
         return template_context
 
     @LoginRequired()
     @HasPermissionAllDecorator('hg.admin')
     @auth.CSRFRequired()
     def settings_post(self):
         """
         View that validates and stores the plugin settings.
         """
         schema = self.plugin.get_settings_schema()
         try:
             valid_data = schema.deserialize(self.request.params)
         except colander.Invalid, e:
             # Display error message and display form again.
             self.request.session.flash(
                 _('Errors exist when saving plugin settings. '
                   'Please check the form inputs.'),
                 queue='error')
             defaults = schema.flatten(self.request.params)
             return self.settings_get(errors=e.asdict(), defaults=defaults)
 
         # Store validated data.
         for name, value in valid_data.items():
             self.plugin.create_or_update_setting(name, value)
         Session.commit()
 
         # Display success message and redirect.
         self.request.session.flash(
             _('Auth settings updated successfully.'),
             queue='success')
         redirect_to = self.request.resource_path(
             self.context, route_name='auth_home')
         return HTTPFound(redirect_to)
 
 
 # TODO: Ongoing migration in these views.
 # - Maybe we should also use a colander schema for these views.
 class AuthSettingsView(object):
     def __init__(self, context, request):
         self.context = context
         self.request = request
 
         # TODO: Move this into a utility function. It is needed in all view
         # classes during migration. Maybe a mixin?
 
         # Some of the decorators rely on this attribute to be present on the
         # class of the decorated method.
         self._rhodecode_user = request.user
 
     @LoginRequired()
     @HasPermissionAllDecorator('hg.admin')
     def index(self, defaults=None, errors=None, prefix_error=False):
         defaults = defaults or {}
         authn_registry = self.request.registry.getUtility(IAuthnPluginRegistry)
         enabled_plugins = SettingsModel().get_auth_plugins()
 
         # Create template context and render it.
         template_context = {
             'resource': self.context,
             'available_plugins': authn_registry.get_plugins(),
             'enabled_plugins': enabled_plugins,
         }
         html = render('rhodecode:templates/admin/auth/auth_settings.html',
                       template_context,
                       request=self.request)
 
         # Create form default values and fill the form.
         form_defaults = {
             'auth_plugins': ','.join(enabled_plugins)
         }
         form_defaults.update(defaults)
         html = formencode.htmlfill.render(
             html,
             defaults=form_defaults,
             errors=errors,
             prefix_error=prefix_error,
             encoding="UTF-8",
             force_defaults=False)
 
         return Response(html)
 
     @LoginRequired()
     @HasPermissionAllDecorator('hg.admin')
     @auth.CSRFRequired()
     def auth_settings(self):
         try:
             form = AuthSettingsForm()()
             form_result = form.to_python(self.request.params)
             plugins = ','.join(form_result['auth_plugins'])
             setting = SettingsModel().create_or_update_setting(
                 'auth_plugins', plugins)
             Session().add(setting)
             Session().commit()
 
             cache_manager = get_auth_cache_manager()
             cache_manager.clear()
             self.request.session.flash(
                 _('Auth settings updated successfully.'),
                 queue='success')
         except formencode.Invalid as errors:
             e = errors.error_dict or {}
             self.request.session.flash(
                 _('Errors exist when saving plugin setting. '
                   'Please check the form inputs.'),
                 queue='error')
             return self.index(
                 defaults=errors.value,
                 errors=e,
                 prefix_error=False)
         except Exception:
             log.exception('Exception in auth_settings')
             self.request.session.flash(
                 _('Error occurred during update of auth settings.'),
                 queue='error')
 
         redirect_to = self.request.resource_path(
             self.context, route_name='auth_home')
         return HTTPFound(redirect_to)