Problem: Need ability for admin to modify dynamic settings

In particular for the 'enforcement override' functionality.

Currently one has to modify the config file and restart services.

Solution: Add the 'Constance' Django plugin and modify logic which
currently uses static settings.

See: https://github.com/jazzband/django-constance

Author: julianpistorius

CHANGELOG.md

@@ -28,6 +28,9 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 ### Fixed
  - Quota updates concerning volumes would silently fail ([#611](https://github.com/cyverse/atmosphere/pull/611))
 
+### Added
+- Added dynamic settings feature ([#613](https://github.com/cyverse/atmosphere/pull/613))
+
 ## [v32-1](https://github.com/cyverse/atmosphere/compare/v32-0...v32-1) - 2018-04-17
 ### Added
  - Support multiple hostnames for Atmosphere(1) server ([#602](https://github.com/cyverse/atmosphere/pull/602))

atmosphere/settings/__init__.py

@@ -51,6 +51,8 @@
 
 # Django uses this one..
 MANAGERS = ADMINS
+CONSTANCE_BACKEND = 'constance.backends.database.DatabaseBackend'
+CONSTANCE_DATABASE_CACHE_BACKEND = 'default'
 
 DATABASES = {
     'default': {
@@ -92,6 +94,8 @@
     'cyverse_allocation',
     'service',
     'core',
+    'constance',
+    'constance.backends.database'
 )
 SESSION_COOKIE_NAME = 'atmo_sessionid'
 

atmosphere/settings/local.py.j2

@@ -4,6 +4,7 @@ Settings specific to the local deploy.
 import os
 import sys
 import logging
+from collections import OrderedDict
 from datetime import timedelta
 from celery.schedules import crontab
 
@@ -500,6 +501,11 @@ TACC_API_PASS = ''
 TACC_API_URL = ''
 {% endif %}
 
+CONSTANCE_CONFIG = OrderedDict([
+    ('ALLOCATION_OVERRIDES_NEVER_ENFORCE', ('', 'Never enforce on these allocation sources. Comma-separated strings.')),
+    ('ALLOCATION_OVERRIDES_ALWAYS_ENFORCE', ('', 'Stop all instances on these allocation sources (nuclear option)')),
+])
+
 ######
 # Atmosphere Plugin Settings
 ######

cyverse_allocation/plugins/allocation_source.py

@@ -1,6 +1,7 @@
 import uuid
 
 from django.conf import settings
+from constance import config as constance_config
 from django.core.exceptions import ObjectDoesNotExist
 from threepio import logger
 
@@ -49,9 +50,9 @@ def _get_enforcement_override(allocation_source):
         """
     assert isinstance(allocation_source, AllocationSource)
     import core.plugins
-    if allocation_source.name in getattr(settings, 'ALLOCATION_OVERRIDES_NEVER_ENFORCE', []):
+    if allocation_source.name in getattr(constance_config, 'ALLOCATION_OVERRIDES_NEVER_ENFORCE', '').split(','):
         return core.plugins.EnforcementOverrideChoice.NEVER_ENFORCE
-    if allocation_source.name in getattr(settings, 'ALLOCATION_OVERRIDES_ALWAYS_ENFORCE', []):
+    if allocation_source.name in getattr(constance_config, 'ALLOCATION_OVERRIDES_ALWAYS_ENFORCE', '').split(','):
         return core.plugins.EnforcementOverrideChoice.ALWAYS_ENFORCE
     return core.plugins.EnforcementOverrideChoice.NO_OVERRIDE
 

dev_requirements.txt

@@ -41,13 +41,15 @@ decorator==4.1.2          # via ipython, traitlets
 defusedxml==0.5.0
 deprecation==1.0.1
 django-celery-beat==1.0.1
+django-constance[database]==2.2.0
 django-cors-headers==2.1.0
 django-cyverse-auth==1.1.4
 django-debug-toolbar==1.8
 django-filter==1.0.4
 django-jenkins==0.110.0
 django-memoize==2.1.0
 django-nose==1.4.4
+django-picklefield==1.0.0
 django-redis-cache==1.7.1
 django-sslserver==0.20
 django==1.11.4

jetstream/plugins/allocation_source.py

@@ -1,4 +1,4 @@
-from django.conf import settings
+from constance import config as constance_config
 
 from core.models import AllocationSource
 
@@ -44,9 +44,9 @@ def _get_enforcement_override(allocation_source):
         """
     assert isinstance(allocation_source, AllocationSource)
     import core.plugins
-    if allocation_source.name in getattr(settings, 'ALLOCATION_OVERRIDES_NEVER_ENFORCE', []):
+    if allocation_source.name in getattr(constance_config, 'ALLOCATION_OVERRIDES_NEVER_ENFORCE', '').split(','):
         return core.plugins.EnforcementOverrideChoice.NEVER_ENFORCE
-    if allocation_source.name in getattr(settings, 'ALLOCATION_OVERRIDES_ALWAYS_ENFORCE', []):
+    if allocation_source.name in getattr(constance_config, 'ALLOCATION_OVERRIDES_ALWAYS_ENFORCE', '').split(','):
         return core.plugins.EnforcementOverrideChoice.ALWAYS_ENFORCE
     return core.plugins.EnforcementOverrideChoice.NO_OVERRIDE
 

requirements.in

@@ -41,6 +41,8 @@ psycopg2
 python-ldap
 uWSGI
 
+django-constance[database]
+
 ## ours
 chromogenic
 django-cyverse-auth

requirements.txt

@@ -31,10 +31,12 @@ debtcollector==1.17.0     # via oslo.config, oslo.context, oslo.log, oslo.utils,
 defusedxml==0.5.0         # via djangorestframework-xml
 deprecation==1.0.1        # via openstacksdk
 django-celery-beat==1.0.1
+django-constance[database]==2.2.0
 django-cors-headers==2.1.0
 django-cyverse-auth==1.1.4
 django-filter==1.0.4
 django-memoize==2.1.0
+django-picklefield==1.0.0  # via django-constance
 django-redis-cache==1.7.1
 django-sslserver==0.20
 django==1.11.4