Add rest API & store for creating push rules

Also make unrecognised request error look more like synapse errors
because it makes it easier to throw them from within rest classes.

synapse/storage/push_rule.py

@@ -0,0 +1,196 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import collections
+
+from ._base import SQLBaseStore, Table
+from twisted.internet import defer
+
+import logging
+import copy
+import json
+
+logger = logging.getLogger(__name__)
+
+
+class PushRuleStore(SQLBaseStore):
+    @defer.inlineCallbacks
+    def get_push_rules_for_user_name(self, user_name):
+        sql = (
+            "SELECT "+",".join(PushRuleTable.fields)+
+            "FROM pushers "
+            "WHERE user_name = ?"
+        )
+
+        rows = yield self._execute(None, sql, user_name)
+
+        dicts = []
+        for r in rows:
+            d = {}
+            for i, f in enumerate(PushRuleTable.fields):
+                d[f] = r[i]
+            dicts.append(d)
+
+        defer.returnValue(dicts)
+
+    @defer.inlineCallbacks
+    def add_push_rule(self, **kwargs):
+        vals = copy.copy(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.
+        if 'id' in vals:
+            del vals['id']
+
+        if 'after' in kwargs or 'before' in kwargs:
+            ret = yield self.runInteraction(
+                "_add_push_rule_relative_txn",
+                self._add_push_rule_relative_txn,
+                **vals
+            )
+            defer.returnValue(ret)
+        else:
+            ret = yield self.runInteraction(
+                "_add_push_rule_highest_priority_txn",
+                self._add_push_rule_highest_priority_txn,
+                **vals
+            )
+            defer.returnValue(ret)
+
+    def _add_push_rule_relative_txn(self, txn, user_name, **kwargs):
+        after = None
+        relative_to_rule = None
+        if 'after' in kwargs and kwargs['after']:
+            after = kwargs['after']
+            relative_to_rule = after
+        if 'before' in kwargs and kwargs['before']:
+            relative_to_rule = kwargs['before']
+
+        # get the priority of the rule we're inserting after/before
+        sql = (
+            "SELECT priority_class, priority FROM "+PushRuleTable.table_name+
+            " WHERE user_name = ? and rule_id = ?"
+        )
+        txn.execute(sql, (user_name, relative_to_rule))
+        res = txn.fetchall()
+        if not res:
+            raise RuleNotFoundException()
+        (priority_class, base_rule_priority) = res[0]
+
+        if 'priority_class' in kwargs and kwargs['priority_class'] != priority_class:
+            raise InconsistentRuleException(
+                "Given priority class does not match class of relative rule"
+            )
+
+        new_rule = copy.copy(kwargs)
+        if 'before' in new_rule:
+            del new_rule['before']
+        if 'after' in new_rule:
+            del new_rule['after']
+        new_rule['priority_class'] = priority_class
+        new_rule['user_name'] = user_name
+
+        # check if the priority before/after is free
+        new_rule_priority = base_rule_priority
+        if after:
+            new_rule_priority -= 1
+        else:
+            new_rule_priority += 1
+
+        new_rule['priority'] = new_rule_priority
+
+        sql = (
+            "SELECT COUNT(*) FROM "+PushRuleTable.table_name+
+            " WHERE user_name = ? AND priority_class = ? AND priority = ?"
+        )
+        txn.execute(sql, (user_name, 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 "+PushRuleTable.table_name+" 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_name, priority_class, new_rule_priority))
+
+        # now insert the new rule
+        sql = "INSERT OR REPLACE INTO "+PushRuleTable.table_name+" ("
+        sql += ",".join(new_rule.keys())+") VALUES ("
+        sql += ", ".join(["?" for _ in new_rule.keys()])+")"
+
+        txn.execute(sql, new_rule.values())
+
+    def _add_push_rule_highest_priority_txn(self, txn, user_name, priority_class, **kwargs):
+        # find the highest priority rule in that class
+        sql = (
+            "SELECT COUNT(*), MAX(priority) FROM "+PushRuleTable.table_name+
+            " WHERE user_name = ? and priority_class = ?"
+        )
+        txn.execute(sql, (user_name, priority_class))
+        res = txn.fetchall()
+        (how_many, highest_prio) = res[0]
+
+        new_prio = 0
+        if how_many > 0:
+            new_prio = highest_prio + 1
+
+        # and insert the new rule
+        new_rule = copy.copy(kwargs)
+        if 'id' in new_rule:
+            del new_rule['id']
+        new_rule['user_name'] = user_name
+        new_rule['priority_class'] = priority_class
+        new_rule['priority'] = new_prio
+
+        sql = "INSERT OR REPLACE INTO "+PushRuleTable.table_name+" ("
+        sql += ",".join(new_rule.keys())+") VALUES ("
+        sql += ", ".join(["?" for _ in new_rule.keys()])+")"
+
+        txn.execute(sql, new_rule.values())
+
+class RuleNotFoundException(Exception):
+    pass
+
+
+class InconsistentRuleException(Exception):
+    pass
+
+
+class PushRuleTable(Table):
+    table_name = "push_rules"
+
+    fields = [
+        "id",
+        "user_name",
+        "rule_id",
+        "priority_class",
+        "priority",
+        "conditions",
+        "actions",
+    ]
+
+    EntryType = collections.namedtuple("PushRuleEntry", fields)