From a9c9868957277408c7ae3956d73ff87964692b73 Mon Sep 17 00:00:00 2001 From: Mark Haines Date: Tue, 16 Feb 2016 15:53:38 +0000 Subject: [PATCH] Make adding push rules idempotent Also remove the **kwargs from the add_push_rule method. Fixes https://matrix.org/jira/browse/SYN-391 --- synapse/storage/push_rule.py | 168 ++++++++++++++++++----------------- 1 file changed, 86 insertions(+), 82 deletions(-) diff --git a/synapse/storage/push_rule.py b/synapse/storage/push_rule.py index f9a48171ba..e19a81e41f 100644 --- a/synapse/storage/push_rule.py +++ b/synapse/storage/push_rule.py @@ -99,38 +99,36 @@ class PushRuleStore(SQLBaseStore): results.setdefault(row['user_name'], {})[row['rule_id']] = row['enabled'] defer.returnValue(results) - @defer.inlineCallbacks - def add_push_rule(self, before, after, **kwargs): - vals = kwargs - if 'conditions' in vals: - vals['conditions'] = json.dumps(vals['conditions']) - if 'actions' in vals: - vals['actions'] = json.dumps(vals['actions']) - - # we could check the rest of the keys are valid column names - # but sqlite will do that anyway so I think it's just pointless. - vals.pop("id", None) + def add_push_rule( + self, user_id, rule_id, priority_class, conditions, actions, + before=None, after=None + ): + conditions_json = json.dumps(conditions) + actions_json = json.dumps(actions) if before or after: - ret = yield self.runInteraction( + return self.runInteraction( "_add_push_rule_relative_txn", self._add_push_rule_relative_txn, - before=before, - after=after, - **vals + user_id, rule_id, priority_class, + conditions_json, actions_json, before, after, ) - defer.returnValue(ret) else: - ret = yield self.runInteraction( + return self.runInteraction( "_add_push_rule_highest_priority_txn", self._add_push_rule_highest_priority_txn, - **vals + user_id, rule_id, priority_class, + conditions_json, actions_json, ) - defer.returnValue(ret) - def _add_push_rule_relative_txn(self, txn, user_id, **kwargs): - after = kwargs.pop("after", None) - before = kwargs.pop("before", None) + def _add_push_rule_relative_txn( + self, txn, user_id, rule_id, priority_class, + conditions_json, actions_json, before, after + ): + # Lock the table since otherwise we'll have annoying races between the + # SELECT here and the UPSERT below. + self.database_engine.lock_table(txn, "push_rules") + relative_to_rule = before or after res = self._simple_select_one_txn( @@ -149,69 +147,45 @@ class PushRuleStore(SQLBaseStore): "before/after rule not found: %s" % (relative_to_rule,) ) - priority_class = res["priority_class"] + base_priority_class = res["priority_class"] base_rule_priority = res["priority"] - if 'priority_class' in kwargs and kwargs['priority_class'] != priority_class: + if base_priority_class != priority_class: raise InconsistentRuleException( "Given priority class does not match class of relative rule" ) - new_rule = kwargs - new_rule.pop("before", None) - new_rule.pop("after", None) - new_rule['priority_class'] = priority_class - new_rule['user_name'] = user_id - new_rule['id'] = self._push_rule_id_gen.get_next_txn(txn) - - # check if the priority before/after is free - new_rule_priority = base_rule_priority - if after: - new_rule_priority -= 1 + if before: + # Higher priority rules are executed first, So adding a rule before + # a rule means giving it a higher priority than that rule. + new_rule_priority = base_rule_priority + 1 else: - new_rule_priority += 1 - - new_rule['priority'] = new_rule_priority + # We increment the priority of the existing rules to make space for + # the new rule. Therefore if we want this rule to appear after + # an existing rule we give it the priority of the existing rule, + # and then increment the priority of the existing rule. + new_rule_priority = base_rule_priority sql = ( - "SELECT COUNT(*) FROM push_rules" - " WHERE user_name = ? AND priority_class = ? AND priority = ?" + "UPDATE push_rules SET priority = priority + 1" + " WHERE user_name = ? AND priority_class = ? AND priority >= ?" ) + txn.execute(sql, (user_id, priority_class, new_rule_priority)) - res = txn.fetchall() - num_conflicting = res[0][0] - # if there are conflicting rules, bump everything - if num_conflicting: - sql = "UPDATE push_rules SET priority = priority " - if after: - sql += "-1" - else: - sql += "+1" - sql += " WHERE user_name = ? AND priority_class = ? AND priority " - if after: - sql += "<= ?" - else: - sql += ">= ?" - - txn.execute(sql, (user_id, priority_class, new_rule_priority)) - - txn.call_after( - self.get_push_rules_for_user.invalidate, (user_id,) + self._upsert_push_rule_txn( + txn, user_id, rule_id, priority_class, new_rule_priority, + conditions_json, actions_json, ) - txn.call_after( - self.get_push_rules_enabled_for_user.invalidate, (user_id,) - ) + def _add_push_rule_highest_priority_txn( + self, txn, user_id, rule_id, priority_class, + conditions_json, actions_json + ): + # Lock the table since otherwise we'll have annoying races between the + # SELECT here and the UPSERT below. + self.database_engine.lock_table(txn, "push_rules") - self._simple_insert_txn( - txn, - table="push_rules", - values=new_rule, - ) - - def _add_push_rule_highest_priority_txn(self, txn, user_id, - priority_class, **kwargs): # find the highest priority rule in that class sql = ( "SELECT COUNT(*), MAX(priority) FROM push_rules" @@ -225,12 +199,48 @@ class PushRuleStore(SQLBaseStore): if how_many > 0: new_prio = highest_prio + 1 - # and insert the new rule - new_rule = kwargs - new_rule['id'] = self._push_rule_id_gen.get_next_txn(txn) - new_rule['user_name'] = user_id - new_rule['priority_class'] = priority_class - new_rule['priority'] = new_prio + self._upsert_push_rule_txn( + txn, + user_id, rule_id, priority_class, new_prio, + conditions_json, actions_json, + ) + + def _upsert_push_rule_txn( + self, txn, user_id, rule_id, priority_class, + priority, conditions_json, actions_json + ): + """Specialised version of _simple_upsert_txn that picks a push_rule_id + using the _push_rule_id_gen if it needs to insert the rule. It assumes + that the "push_rules" table is locked""" + + sql = ( + "UPDATE push_rules" + " SET priority_class = ?, priority = ?, conditions = ?, actions = ?" + " WHERE user_name = ? AND rule_id = ?" + ) + + txn.execute(sql, ( + priority_class, priority, conditions_json, actions_json, + user_id, rule_id, + )) + + if txn.rowcount == 0: + # We didn't update a row with the given rule_id so insert one + push_rule_id = self._push_rule_id_gen.get_next_txn(txn) + + self._simple_insert_txn( + txn, + table="push_rules", + values={ + "id": push_rule_id, + "user_name": user_id, + "rule_id": rule_id, + "priority_class": priority_class, + "priority": priority, + "conditions": conditions_json, + "actions": actions_json, + }, + ) txn.call_after( self.get_push_rules_for_user.invalidate, (user_id,) @@ -239,12 +249,6 @@ class PushRuleStore(SQLBaseStore): self.get_push_rules_enabled_for_user.invalidate, (user_id,) ) - self._simple_insert_txn( - txn, - table="push_rules", - values=new_rule, - ) - @defer.inlineCallbacks def delete_push_rule(self, user_id, rule_id): """