Merge pull request #2896 from matrix-org/erikj/split_receipts_store

Split ReceiptsStore

2 files changed, 76 insertions, 48 deletions

diff --git a/synapse/storage/__init__.py b/synapse/storage/__init__.py
index f8fbd02ceb..e1c4fe086e 100644
--- a/synapse/storage/__init__.py
+++ b/synapse/storage/__init__.py
@@ -104,9 +104,6 @@ class DataStore(RoomMemberStore, RoomStore,
             db_conn, "events", "stream_ordering", step=-1,
             extra_tables=[("ex_outlier_stream", "event_stream_ordering")]
         )
-        self._receipts_id_gen = StreamIdGenerator(
-            db_conn, "receipts_linearized", "stream_id"
-        )
         self._account_data_id_gen = StreamIdGenerator(
             db_conn, "account_data_max_stream_id", "stream_id"
         )
diff --git a/synapse/storage/receipts.py b/synapse/storage/receipts.py
index 12b3cc7f5f..40530632c6 100644
--- a/synapse/storage/receipts.py
+++ b/synapse/storage/receipts.py
@@ -1,5 +1,6 @@
 # -*- coding: utf-8 -*-
 # Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2018 New Vector Ltd
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -14,11 +15,13 @@
 # limitations under the License.
 
 from ._base import SQLBaseStore
+from .util.id_generators import StreamIdGenerator
 from synapse.util.caches.descriptors import cachedInlineCallbacks, cachedList, cached
 from synapse.util.caches.stream_change_cache import StreamChangeCache
 
 from twisted.internet import defer
 
+import abc
 import logging
 import ujson as json
 
@@ -26,39 +29,36 @@ import ujson as json
 logger = logging.getLogger(__name__)
 
 
-class ReceiptsStore(SQLBaseStore):
+class ReceiptsWorkerStore(SQLBaseStore):
+    """This is an abstract base class where subclasses must implement
+    `get_max_receipt_stream_id` which can be called in the initializer.
+    """
+
+    # This ABCMeta metaclass ensures that we cannot be instantiated without
+    # the abstract methods being implemented.
+    __metaclass__ = abc.ABCMeta
+
     def __init__(self, db_conn, hs):
-        super(ReceiptsStore, self).__init__(db_conn, hs)
+        super(ReceiptsWorkerStore, self).__init__(db_conn, hs)
 
         self._receipts_stream_cache = StreamChangeCache(
-            "ReceiptsRoomChangeCache", self._receipts_id_gen.get_current_token()
+            "ReceiptsRoomChangeCache", self.get_max_receipt_stream_id()
         )
 
+    @abc.abstractmethod
+    def get_max_receipt_stream_id(self):
+        """Get the current max stream ID for receipts stream
+
+        Returns:
+            int
+        """
+        raise NotImplementedError()
+
     @cachedInlineCallbacks()
     def get_users_with_read_receipts_in_room(self, room_id):
         receipts = yield self.get_receipts_for_room(room_id, "m.read")
         defer.returnValue(set(r['user_id'] for r in receipts))
 
-    def _invalidate_get_users_with_receipts_in_room(self, room_id, receipt_type,
-                                                    user_id):
-        if receipt_type != "m.read":
-            return
-
-        # Returns an ObservableDeferred
-        res = self.get_users_with_read_receipts_in_room.cache.get(
-            room_id, None, update_metrics=False,
-        )
-
-        if res:
-            if isinstance(res, defer.Deferred) and res.called:
-                res = res.result
-            if user_id in res:
-                # We'd only be adding to the set, so no point invalidating if the
-                # user is already there
-                return
-
-        self.get_users_with_read_receipts_in_room.invalidate((room_id,))
-
     @cached(num_args=2)
     def get_receipts_for_room(self, room_id, receipt_type):
         return self._simple_select_list(
@@ -270,9 +270,62 @@ class ReceiptsStore(SQLBaseStore):
         }
         defer.returnValue(results)
 
+    def get_all_updated_receipts(self, last_id, current_id, limit=None):
+        if last_id == current_id:
+            return defer.succeed([])
+
+        def get_all_updated_receipts_txn(txn):
+            sql = (
+                "SELECT stream_id, room_id, receipt_type, user_id, event_id, data"
+                " FROM receipts_linearized"
+                " WHERE ? < stream_id AND stream_id <= ?"
+                " ORDER BY stream_id ASC"
+            )
+            args = [last_id, current_id]
+            if limit is not None:
+                sql += " LIMIT ?"
+                args.append(limit)
+            txn.execute(sql, args)
+
+            return txn.fetchall()
+        return self.runInteraction(
+            "get_all_updated_receipts", get_all_updated_receipts_txn
+        )
+
+
+class ReceiptsStore(ReceiptsWorkerStore):
+    def __init__(self, db_conn, hs):
+        # We instantiate this first as the ReceiptsWorkerStore constructor
+        # needs to be able to call get_max_receipt_stream_id
+        self._receipts_id_gen = StreamIdGenerator(
+            db_conn, "receipts_linearized", "stream_id"
+        )
+
+        super(ReceiptsStore, self).__init__(db_conn, hs)
+
     def get_max_receipt_stream_id(self):
         return self._receipts_id_gen.get_current_token()
 
+    def _invalidate_get_users_with_receipts_in_room(self, room_id, receipt_type,
+                                                    user_id):
+        if receipt_type != "m.read":
+            return
+
+        # Returns an ObservableDeferred
+        res = self.get_users_with_read_receipts_in_room.cache.get(
+            room_id, None, update_metrics=False,
+        )
+
+        if res:
+            if isinstance(res, defer.Deferred) and res.called:
+                res = res.result
+            if user_id in res:
+                # We'd only be adding to the set, so no point invalidating if the
+                # user is already there
+                return
+
+        self.get_users_with_read_receipts_in_room.invalidate((room_id,))
+
     def insert_linearized_receipt_txn(self, txn, room_id, receipt_type,
                                       user_id, event_id, data, stream_id):
         txn.call_after(
@@ -457,25 +510,3 @@ class ReceiptsStore(SQLBaseStore):
                 "data": json.dumps(data),
             }
         )
-
-    def get_all_updated_receipts(self, last_id, current_id, limit=None):
-        if last_id == current_id:
-            return defer.succeed([])
-
-        def get_all_updated_receipts_txn(txn):
-            sql = (
-                "SELECT stream_id, room_id, receipt_type, user_id, event_id, data"
-                " FROM receipts_linearized"
-                " WHERE ? < stream_id AND stream_id <= ?"
-                " ORDER BY stream_id ASC"
-            )
-            args = [last_id, current_id]
-            if limit is not None:
-                sql += " LIMIT ?"
-                args.append(limit)
-            txn.execute(sql, args)
-
-            return txn.fetchall()
-        return self.runInteraction(
-            "get_all_updated_receipts", get_all_updated_receipts_txn
-        )