patch by braph: use decorator for config lock, drop IPC lock

common.py

@@ -7,6 +7,7 @@ import time
 import requests
 from collections import namedtuple
 from urllib.error import URLError
+import threading
 
 RATE_NO_LIMIT = 0x00
 RATE_GLOBAL = 0x01
@@ -43,6 +44,8 @@ buckets = {
 
 rate_limit_classes = buckets.keys()
 
+plugin_lock = threading.Lock()
+
 
 def rate_limit(rate_class=RATE_GLOBAL):
     """
@@ -182,6 +185,23 @@ def giphy(subject, api_key):
     return giphy_url
 
 
+def config_locked(f):
+    """A decorator that makes access to the config thread-safe"""
+
+    def decorate(*args, **kwargs):
+
+        plugin_lock.acquire()
+
+        try:
+            return f(*args, **kwargs)
+        except:
+            raise
+        finally:
+            plugin_lock.release()
+
+    return decorate
+
+
 def pluginfunction(name, desc, plugin_type, ratelimit_class=RATE_GLOBAL, enabled=True):
     """A decorator to make a plugin out of a function
     :param enabled:

local_config.ini.spec

@@ -14,7 +14,6 @@ hist_max_count = integer(default=5)
 hist_max_time = integer(default=10*60)
 
 persistent_storage = string(default='urlbot.persistent')
-persistent_locked = boolean(default=false)
 
 # the "dice" feature will use more efficient random data (0) for given users
 enhanced-random-user = string_list(default=list())

plugins/__init__.py

@@ -5,7 +5,7 @@ import traceback
 import types
 
 import config
-from common import RATE_NO_LIMIT, pluginfunction, ptypes_PARSE, ptypes_COMMAND, ptypes_MUC_ONLINE, ptypes
+from common import RATE_NO_LIMIT, pluginfunction, config_locked, ptypes_PARSE, ptypes_COMMAND, ptypes_MUC_ONLINE, ptypes
 from plugins import commands, parsers, muc_online
 
 joblist = []
@@ -21,18 +21,14 @@ def plugin_enabled_get(urlbot_plugin):
         return urlbot_plugin.is_enabled
 
 
+@config_locked
 def plugin_enabled_set(plugin, enabled):
-    if config.conf_get('persistent_locked'):
-        log.warn("couldn't get exclusive lock")
-
-    config.conf_set('persistent_locked', True)
 
     if plugin.plugin_name not in config.runtime_config_store['plugins']:
         config.runtime_config_store['plugins'][plugin.plugin_name] = {}
 
     config.runtime_config_store['plugins'][plugin.plugin_name]['enabled'] = enabled
     config.runtimeconf_persist()
-    config.conf_set('persistent_locked', False)
 
 
 def register_active_event(t, callback, args, action_runner, plugin, msg_obj):

plugins/commands.py

@@ -13,7 +13,7 @@ from lxml import etree
 import config
 from common import (
     VERSION, RATE_FUN, RATE_GLOBAL, RATE_INTERACTIVE, RATE_NO_LIMIT,
-    giphy, pluginfunction,
+    giphy, pluginfunction, config_locked,
     ptypes_COMMAND,
     RATE_NO_SILENCE,
     get_nick_from_object
@@ -340,6 +340,7 @@ def usersetting_get(argv, args):
 
 
 @pluginfunction('set', 'modify a user setting', ptypes_COMMAND, ratelimit_class=RATE_NO_LIMIT)
+@config_locked
 def command_usersetting(argv, **args):
     settings = ['spoiler']
     arg_user = args['reply_user']
@@ -360,20 +361,12 @@ def command_usersetting(argv, **args):
         # display current value
         return usersetting_get(argv, args)
 
-    if config.conf_get('persistent_locked'):
-        return {
-            'msg': args['reply_user'] + ''': couldn't get exclusive lock'''
-        }
-
-    config.conf_set('persistent_locked', True)
-
     if arg_user not in config.runtime_config_store['user_pref']:
         config.runtime_config_store['user_pref'][arg_user] = {}
 
     config.runtime_config_store['user_pref'][arg_user][arg_key] = 'on' == arg_val
 
     config.runtimeconf_persist()
-    config.conf_set('persistent_locked', False)
 
     # display value written to db
     return usersetting_get(argv, args)
@@ -482,6 +475,7 @@ def command_show_moinlist(argv, **args):
 @pluginfunction(
     'record', 'record a message for a now offline user (usage: record {user} {some message};'
               ' {some message} == "previous" to use the last channel message)', ptypes_COMMAND)
+@config_locked
 def command_record(argv, **args):
     if len(argv) < 2:
         return {
@@ -497,20 +491,12 @@ def command_record(argv, **args):
     else:
         message += ' '.join(argv[1:])
 
-    if config.conf_get('persistent_locked'):
-        return {
-            'msg': "%s: couldn't get exclusive lock" % args['reply_user']
-        }
-
-    config.conf_set('persistent_locked', True)
-
     if target_user not in config.runtime_config_store['user_records']:
         config.runtime_config_store['user_records'][target_user] = []
 
     config.runtime_config_store['user_records'][target_user].append(message)
 
     config.runtimeconf_persist()
-    config.conf_set('persistent_locked', False)
 
     return {
         'msg': '%s: message saved for %s' % (args['reply_user'], target_user)

plugins/muc_online.py

@@ -2,7 +2,7 @@ import logging
 
 import config
 from common import (
-    pluginfunction,
+    pluginfunction, config_locked,
     ptypes_MUC_ONLINE
 )
 
@@ -10,6 +10,7 @@ log = logging.getLogger(__name__)
 
 
 @pluginfunction('send_record', 'delivers previously saved message to user', ptypes_MUC_ONLINE)
+@config_locked
 def send_record(**args):
     arg_user = args['reply_user']
     arg_user_key = arg_user.lower()
@@ -31,15 +32,7 @@ def send_record(**args):
                 )
         }
 
-        if config.conf_get('persistent_locked'):
-            log.warning("couldn't get exclusive lock")
-            return None
-
-        config.conf_set('persistent_locked', True)
-
         user_records.pop(arg_user_key)
         config.runtimeconf_persist()
 
-        config.conf_set('persistent_locked', False)
-
         return response