State events filtering database api (#438)

This PR adds a gomatrixserverlib.Filter parameter to functions handling the syncapi_current_room_state table. It does not implement any filtering logic inside the syncapi IncrementalSync/CompleteSync functions, just the APIs for future use.

Default filters are provided as placeholders in IncrementalSync/CompleteSync, so behaviour should be unchanged (except the default 20 event limit)

SQL table will be changed. You can upgrade an existing database using:

```
ALTER TABLE syncapi_current_room_state  ADD COLUMN IF NOT EXISTS sender text;
UPDATE syncapi_current_room_state SET sender=(event_json::json->>'sender');
ALTER TABLE syncapi_current_room_state ALTER COLUMN sender SET NOT NULL;
ALTER TABLE syncapi_current_room_state  ADD COLUMN IF NOT EXISTS contains_url bool;
UPDATE syncapi_current_room_state SET contains_url=(event_json::json->>'content')::json->>'url' IS NOT NULL;
ALTER TABLE syncapi_current_room_state ALTER COLUMN contains_url SET NOT NULL;
```

Note: This depends on #436 (and includes all its commits). I'm not sure if Github will remove the duplicated commits once #436 is merged.

syncapi/routing/state.go

@@ -44,7 +44,10 @@ func OnIncomingStateRequest(req *http.Request, db *storage.SyncServerDatasource,
 	// TODO(#287): Auth request and handle the case where the user has left (where
 	// we should return the state at the poin they left)
 
-	stateEvents, err := db.GetStateEventsForRoom(req.Context(), roomID)
+	stateFilterPart := gomatrixserverlib.DefaultFilterPart()
+	// TODO: stateFilterPart should not limit the number of state events (or only limits abusive number of events)
+
+	stateEvents, err := db.GetStateEventsForRoom(req.Context(), roomID, &stateFilterPart)
 	if err != nil {
 		return httputil.LogThenError(req, err)
 	}

syncapi/storage/current_room_state_table.go

@@ -17,6 +17,7 @@ package storage
 import (
 	"context"
 	"database/sql"
+	"encoding/json"
 
 	"github.com/lib/pq"
 	"github.com/matrix-org/dendrite/common"
@@ -32,6 +33,10 @@ CREATE TABLE IF NOT EXISTS syncapi_current_room_state (
     event_id TEXT NOT NULL,
     -- The state event type e.g 'm.room.member'
     type TEXT NOT NULL,
+    -- The 'sender' property of the event.
+    sender TEXT NOT NULL,
+	-- true if the event content contains a url key
+    contains_url BOOL NOT NULL,
     -- The state_key value for this state event e.g ''
     state_key TEXT NOT NULL,
     -- The JSON for the event. Stored as TEXT because this should be valid UTF-8.
@@ -46,16 +51,16 @@ CREATE TABLE IF NOT EXISTS syncapi_current_room_state (
     CONSTRAINT syncapi_room_state_unique UNIQUE (room_id, type, state_key)
 );
 -- for event deletion
-CREATE UNIQUE INDEX IF NOT EXISTS syncapi_event_id_idx ON syncapi_current_room_state(event_id);
+CREATE UNIQUE INDEX IF NOT EXISTS syncapi_event_id_idx ON syncapi_current_room_state(event_id, room_id, type, sender, contains_url);
 -- for querying membership states of users
 CREATE INDEX IF NOT EXISTS syncapi_membership_idx ON syncapi_current_room_state(type, state_key, membership) WHERE membership IS NOT NULL AND membership != 'leave';
 `
 
 const upsertRoomStateSQL = "" +
-	"INSERT INTO syncapi_current_room_state (room_id, event_id, type, state_key, event_json, membership, added_at)" +
+	"INSERT INTO syncapi_current_room_state (room_id, event_id, type, sender, contains_url, state_key, event_json, membership, added_at)" +
-	" VALUES ($1, $2, $3, $4, $5, $6, $7)" +
+	" VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9)" +
 	" ON CONFLICT ON CONSTRAINT syncapi_room_state_unique" +
-	" DO UPDATE SET event_id = $2, event_json = $5, membership = $6, added_at = $7"
+	" DO UPDATE SET event_id = $2, sender=$4, contains_url=$5, event_json = $7, membership = $8, added_at = $9"
 
 const deleteRoomStateByEventIDSQL = "" +
 	"DELETE FROM syncapi_current_room_state WHERE event_id = $1"
@@ -64,7 +69,13 @@ const selectRoomIDsWithMembershipSQL = "" +
 	"SELECT room_id FROM syncapi_current_room_state WHERE type = 'm.room.member' AND state_key = $1 AND membership = $2"
 
 const selectCurrentStateSQL = "" +
-	"SELECT event_json FROM syncapi_current_room_state WHERE room_id = $1"
+	"SELECT event_json FROM syncapi_current_room_state WHERE room_id = $1" +
+	" AND ( $2::text[] IS NULL OR     sender  = ANY($2)  )" +
+	" AND ( $3::text[] IS NULL OR NOT(sender  = ANY($3)) )" +
+	" AND ( $4::text[] IS NULL OR     type LIKE ANY($4)  )" +
+	" AND ( $5::text[] IS NULL OR NOT(type LIKE ANY($5)) )" +
+	" AND ( $6::bool IS NULL   OR     contains_url = $6  )" +
+	" LIMIT $7"
 
 const selectJoinedUsersSQL = "" +
 	"SELECT room_id, state_key FROM syncapi_current_room_state WHERE type = 'm.room.member' AND membership = 'join'"
@@ -166,9 +177,17 @@ func (s *currentRoomStateStatements) selectRoomIDsWithMembership(
 // CurrentState returns all the current state events for the given room.
 func (s *currentRoomStateStatements) selectCurrentState(
 	ctx context.Context, txn *sql.Tx, roomID string,
+	stateFilterPart *gomatrixserverlib.FilterPart,
 ) ([]gomatrixserverlib.Event, error) {
 	stmt := common.TxStmt(txn, s.selectCurrentStateStmt)
-	rows, err := stmt.QueryContext(ctx, roomID)
+	rows, err := stmt.QueryContext(ctx, roomID,
+		pq.StringArray(stateFilterPart.Senders),
+		pq.StringArray(stateFilterPart.NotSenders),
+		pq.StringArray(filterConvertTypeWildcardToSQL(stateFilterPart.Types)),
+		pq.StringArray(filterConvertTypeWildcardToSQL(stateFilterPart.NotTypes)),
+		stateFilterPart.ContainsURL,
+		stateFilterPart.Limit,
+	)
 	if err != nil {
 		return nil, err
 	}
@@ -189,12 +208,23 @@ func (s *currentRoomStateStatements) upsertRoomState(
 	ctx context.Context, txn *sql.Tx,
 	event gomatrixserverlib.Event, membership *string, addedAt int64,
 ) error {
+	// Parse content as JSON and search for an "url" key
+	containsURL := false
+	var content map[string]interface{}
+	if json.Unmarshal(event.Content(), &content) != nil {
+		// Set containsURL to true if url is present
+		_, containsURL = content["url"]
+	}
+
+	// upsert state event
 	stmt := common.TxStmt(txn, s.upsertRoomStateStmt)
 	_, err := stmt.ExecContext(
 		ctx,
 		event.RoomID(),
 		event.EventID(),
 		event.Type(),
+		event.Sender(),
+		containsURL,
 		*event.StateKey(),
 		event.JSON(),
 		membership,

syncapi/storage/filtering.go

@@ -0,0 +1,36 @@
+// Copyright 2017 Thibaut CHARLES
+//
+// 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.
+
+package storage
+
+import (
+	"strings"
+)
+
+// filterConvertWildcardToSQL converts wildcards as defined in
+// https://matrix.org/docs/spec/client_server/r0.3.0.html#post-matrix-client-r0-user-userid-filter
+// to SQL wildcards that can be used with LIKE()
+func filterConvertTypeWildcardToSQL(values []string) []string {
+	if values == nil {
+		// Return nil instead of []string{} so IS NULL can work correctly when
+		// the return value is passed into SQL queries
+		return nil
+	}
+
+	ret := make([]string, len(values))
+	for i := range values {
+		ret[i] = strings.Replace(values[i], "*", "%", -1)
+	}
+	return ret
+}

syncapi/storage/output_room_events_table.go

@@ -17,6 +17,7 @@ package storage
 import (
 	"context"
 	"database/sql"
+	"encoding/json"
 	"sort"
 
 	"github.com/matrix-org/dendrite/roomserver/api"
@@ -43,6 +44,12 @@ CREATE TABLE IF NOT EXISTS syncapi_output_room_events (
     room_id TEXT NOT NULL,
     -- The JSON for the event. Stored as TEXT because this should be valid UTF-8.
     event_json TEXT NOT NULL,
+    -- The event type e.g 'm.room.member'.
+    type TEXT NOT NULL,
+    -- The 'sender' property of the event.
+    sender TEXT NOT NULL,
+	-- true if the event content contains a url key.
+    contains_url BOOL NOT NULL,
     -- A list of event IDs which represent a delta of added/removed room state. This can be NULL
     -- if there is no delta.
     add_state_ids TEXT[],
@@ -56,8 +63,8 @@ CREATE UNIQUE INDEX IF NOT EXISTS syncapi_event_id_idx ON syncapi_output_room_ev
 
 const insertEventSQL = "" +
 	"INSERT INTO syncapi_output_room_events (" +
-	" room_id, event_id, event_json, add_state_ids, remove_state_ids, device_id, transaction_id" +
+	"room_id, event_id, event_json, type, sender, contains_url, add_state_ids, remove_state_ids, device_id, transaction_id" +
-	") VALUES ($1, $2, $3, $4, $5, $6, $7) RETURNING id"
+	") VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10) RETURNING id"
 
 const selectEventsSQL = "" +
 	"SELECT id, event_json FROM syncapi_output_room_events WHERE event_id = ANY($1)"
@@ -75,7 +82,13 @@ const selectStateInRangeSQL = "" +
 	"SELECT id, event_json, add_state_ids, remove_state_ids" +
 	" FROM syncapi_output_room_events" +
 	" WHERE (id > $1 AND id <= $2) AND (add_state_ids IS NOT NULL OR remove_state_ids IS NOT NULL)" +
-	" ORDER BY id ASC"
+	" AND ( $3::text[] IS NULL OR     sender  = ANY($3)  )" +
+	" AND ( $4::text[] IS NULL OR NOT(sender  = ANY($4)) )" +
+	" AND ( $5::text[] IS NULL OR     type LIKE ANY($5)  )" +
+	" AND ( $6::text[] IS NULL OR NOT(type LIKE ANY($6)) )" +
+	" AND ( $7::bool IS NULL   OR     contains_url = $7  )" +
+	" ORDER BY id ASC" +
+	" LIMIT $8"
 
 type outputRoomEventsStatements struct {
 	insertEventStmt        *sql.Stmt
@@ -113,10 +126,19 @@ func (s *outputRoomEventsStatements) prepare(db *sql.DB) (err error) {
 // two positions, only the most recent state is returned.
 func (s *outputRoomEventsStatements) selectStateInRange(
 	ctx context.Context, txn *sql.Tx, oldPos, newPos int64,
+	stateFilterPart *gomatrixserverlib.FilterPart,
 ) (map[string]map[string]bool, map[string]streamEvent, error) {
 	stmt := common.TxStmt(txn, s.selectStateInRangeStmt)
 
-	rows, err := stmt.QueryContext(ctx, oldPos, newPos)
+	rows, err := stmt.QueryContext(
+		ctx, oldPos, newPos,
+		pq.StringArray(stateFilterPart.Senders),
+		pq.StringArray(stateFilterPart.NotSenders),
+		pq.StringArray(filterConvertTypeWildcardToSQL(stateFilterPart.Types)),
+		pq.StringArray(filterConvertTypeWildcardToSQL(stateFilterPart.NotTypes)),
+		stateFilterPart.ContainsURL,
+		stateFilterPart.Limit,
+	)
 	if err != nil {
 		return nil, nil, err
 	}
@@ -205,12 +227,23 @@ func (s *outputRoomEventsStatements) insertEvent(
 		txnID = &transactionID.TransactionID
 	}
 
+	// Parse content as JSON and search for an "url" key
+	containsURL := false
+	var content map[string]interface{}
+	if json.Unmarshal(event.Content(), &content) != nil {
+		// Set containsURL to true if url is present
+		_, containsURL = content["url"]
+	}
+
 	stmt := common.TxStmt(txn, s.insertEventStmt)
 	err = stmt.QueryRowContext(
 		ctx,
 		event.RoomID(),
 		event.EventID(),
 		event.JSON(),
+		event.Type(),
+		event.Sender(),
+		containsURL,
 		pq.StringArray(addState),
 		pq.StringArray(removeState),
 		deviceID,

syncapi/storage/syncserver.go

@@ -185,10 +185,10 @@ func (d *SyncServerDatasource) GetStateEvent(
 // Returns an empty slice if no state events could be found for this room.
 // Returns an error if there was an issue with the retrieval.
 func (d *SyncServerDatasource) GetStateEventsForRoom(
-	ctx context.Context, roomID string,
+	ctx context.Context, roomID string, stateFilterPart *gomatrixserverlib.FilterPart,
 ) (stateEvents []gomatrixserverlib.Event, err error) {
 	err = common.WithTransaction(d.db, func(txn *sql.Tx) error {
-		stateEvents, err = d.roomstate.selectCurrentState(ctx, txn, roomID)
+		stateEvents, err = d.roomstate.selectCurrentState(ctx, txn, roomID, stateFilterPart)
 		return err
 	})
 	return
@@ -245,6 +245,8 @@ func (d *SyncServerDatasource) addPDUDeltaToResponse(
 	var succeeded bool
 	defer common.EndTransaction(txn, &succeeded)
 
+	stateFilterPart := gomatrixserverlib.DefaultFilterPart() // TODO: use filter provided in request
+
 	// Work out which rooms to return in the response. This is done by getting not only the currently
 	// joined rooms, but also which rooms have membership transitions for this user between the 2 PDU stream positions.
 	// This works out what the 'state' key should be for each room as well as which membership block
@@ -252,9 +254,13 @@ func (d *SyncServerDatasource) addPDUDeltaToResponse(
 	var deltas []stateDelta
 	var joinedRoomIDs []string
 	if !wantFullState {
-		deltas, joinedRoomIDs, err = d.getStateDeltas(ctx, &device, txn, fromPos, toPos, device.UserID)
+		deltas, joinedRoomIDs, err = d.getStateDeltas(
+			ctx, &device, txn, fromPos, toPos, device.UserID, &stateFilterPart,
+		)
 	} else {
-		deltas, joinedRoomIDs, err = d.getStateDeltasForFullStateSync(ctx, &device, txn, fromPos, toPos, device.UserID)
+		deltas, joinedRoomIDs, err = d.getStateDeltasForFullStateSync(
+			ctx, &device, txn, fromPos, toPos, device.UserID, &stateFilterPart,
+		)
 	}
 	if err != nil {
 		return nil, err
@@ -404,10 +410,12 @@ func (d *SyncServerDatasource) getResponseWithPDUsForCompleteSync(
 		return
 	}
 
+	stateFilterPart := gomatrixserverlib.DefaultFilterPart() // TODO: use filter provided in request
+
 	// Build up a /sync response. Add joined rooms.
 	for _, roomID := range joinedRoomIDs {
 		var stateEvents []gomatrixserverlib.Event
-		stateEvents, err = d.roomstate.selectCurrentState(ctx, txn, roomID)
+		stateEvents, err = d.roomstate.selectCurrentState(ctx, txn, roomID, &stateFilterPart)
 		if err != nil {
 			return
 		}
@@ -733,6 +741,7 @@ func (d *SyncServerDatasource) fetchMissingStateEvents(
 func (d *SyncServerDatasource) getStateDeltas(
 	ctx context.Context, device *authtypes.Device, txn *sql.Tx,
 	fromPos, toPos int64, userID string,
+	stateFilterPart *gomatrixserverlib.FilterPart,
 ) ([]stateDelta, []string, error) {
 	// Implement membership change algorithm: https://github.com/matrix-org/synapse/blob/v0.19.3/synapse/handlers/sync.py#L821
 	// - Get membership list changes for this user in this sync response
@@ -745,7 +754,7 @@ func (d *SyncServerDatasource) getStateDeltas(
 	var deltas []stateDelta
 
 	// get all the state events ever between these two positions
-	stateNeeded, eventMap, err := d.events.selectStateInRange(ctx, txn, fromPos, toPos)
+	stateNeeded, eventMap, err := d.events.selectStateInRange(ctx, txn, fromPos, toPos, stateFilterPart)
 	if err != nil {
 		return nil, nil, err
 	}
@@ -765,7 +774,7 @@ func (d *SyncServerDatasource) getStateDeltas(
 				if membership == gomatrixserverlib.Join {
 					// send full room state down instead of a delta
 					var s []streamEvent
-					s, err = d.currentStateStreamEventsForRoom(ctx, txn, roomID)
+					s, err = d.currentStateStreamEventsForRoom(ctx, txn, roomID, stateFilterPart)
 					if err != nil {
 						return nil, nil, err
 					}
@@ -807,6 +816,7 @@ func (d *SyncServerDatasource) getStateDeltas(
 func (d *SyncServerDatasource) getStateDeltasForFullStateSync(
 	ctx context.Context, device *authtypes.Device, txn *sql.Tx,
 	fromPos, toPos int64, userID string,
+	stateFilterPart *gomatrixserverlib.FilterPart,
 ) ([]stateDelta, []string, error) {
 	joinedRoomIDs, err := d.roomstate.selectRoomIDsWithMembership(ctx, txn, userID, gomatrixserverlib.Join)
 	if err != nil {
@@ -818,7 +828,7 @@ func (d *SyncServerDatasource) getStateDeltasForFullStateSync(
 
 	// Add full states for all joined rooms
 	for _, joinedRoomID := range joinedRoomIDs {
-		s, stateErr := d.currentStateStreamEventsForRoom(ctx, txn, joinedRoomID)
+		s, stateErr := d.currentStateStreamEventsForRoom(ctx, txn, joinedRoomID, stateFilterPart)
 		if stateErr != nil {
 			return nil, nil, stateErr
 		}
@@ -830,7 +840,7 @@ func (d *SyncServerDatasource) getStateDeltasForFullStateSync(
 	}
 
 	// Get all the state events ever between these two positions
-	stateNeeded, eventMap, err := d.events.selectStateInRange(ctx, txn, fromPos, toPos)
+	stateNeeded, eventMap, err := d.events.selectStateInRange(ctx, txn, fromPos, toPos, stateFilterPart)
 	if err != nil {
 		return nil, nil, err
 	}
@@ -861,8 +871,9 @@ func (d *SyncServerDatasource) getStateDeltasForFullStateSync(
 
 func (d *SyncServerDatasource) currentStateStreamEventsForRoom(
 	ctx context.Context, txn *sql.Tx, roomID string,
+	stateFilterPart *gomatrixserverlib.FilterPart,
 ) ([]streamEvent, error) {
-	allState, err := d.roomstate.selectCurrentState(ctx, txn, roomID)
+	allState, err := d.roomstate.selectCurrentState(ctx, txn, roomID, stateFilterPart)
 	if err != nil {
 		return nil, err
 	}