Implement storage interfaces (#841)

* Implement interfaces for federationsender storage

* Implement interfaces for mediaapi storage

* Implement interfaces for publicroomsapi storage

* Implement interfaces for roomserver storage

* Implement interfaces for syncapi storage

* Implement interfaces for keydb storage

* common.PartitionStorer in publicroomsapi interface

* Update copyright notices

roomserver/storage/postgres/membership_table.go

@@ -0,0 +1,194 @@
+// Copyright 2017-2018 New Vector Ltd
+// Copyright 2019-2020 The Matrix.org Foundation C.I.C.
+//
+// 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 postgres
+
+import (
+	"context"
+	"database/sql"
+
+	"github.com/matrix-org/dendrite/common"
+	"github.com/matrix-org/dendrite/roomserver/types"
+)
+
+type membershipState int64
+
+const (
+	membershipStateLeaveOrBan membershipState = 1
+	membershipStateInvite     membershipState = 2
+	membershipStateJoin       membershipState = 3
+)
+
+const membershipSchema = `
+-- The membership table is used to coordinate updates between the invite table
+-- and the room state tables.
+-- This table is updated in one of 3 ways:
+--   1) The membership of a user changes within the current state of the room.
+--   2) An invite is received outside of a room over federation.
+--   3) An invite is rejected outside of a room over federation.
+CREATE TABLE IF NOT EXISTS roomserver_membership (
+	room_nid BIGINT NOT NULL,
+	-- Numeric state key ID for the user ID this state is for.
+	target_nid BIGINT NOT NULL,
+	-- Numeric state key ID for the user ID who changed the state.
+	-- This may be 0 since it is not always possible to identify the user that
+	-- changed the state.
+	sender_nid BIGINT NOT NULL DEFAULT 0,
+	-- The state the user is in within this room.
+	-- Default value is "membershipStateLeaveOrBan"
+	membership_nid BIGINT NOT NULL DEFAULT 1,
+	-- The numeric ID of the membership event.
+	-- It refers to the join membership event if the membership_nid is join (3),
+	-- and to the leave/ban membership event if the membership_nid is leave or
+	-- ban (1).
+	-- If the membership_nid is invite (2) and the user has been in the room
+	-- before, it will refer to the previous leave/ban membership event, and will
+	-- be equals to 0 (its default) if the user never joined the room before.
+	-- This NID is updated if the join event gets updated (e.g. profile update),
+	-- or if the user leaves/joins the room.
+	event_nid BIGINT NOT NULL DEFAULT 0,
+	UNIQUE (room_nid, target_nid)
+);
+`
+
+// Insert a row in to membership table so that it can be locked by the
+// SELECT FOR UPDATE
+const insertMembershipSQL = "" +
+	"INSERT INTO roomserver_membership (room_nid, target_nid)" +
+	" VALUES ($1, $2)" +
+	" ON CONFLICT DO NOTHING"
+
+const selectMembershipFromRoomAndTargetSQL = "" +
+	"SELECT membership_nid, event_nid FROM roomserver_membership" +
+	" WHERE room_nid = $1 AND target_nid = $2"
+
+const selectMembershipsFromRoomAndMembershipSQL = "" +
+	"SELECT event_nid FROM roomserver_membership" +
+	" WHERE room_nid = $1 AND membership_nid = $2"
+
+const selectMembershipsFromRoomSQL = "" +
+	"SELECT event_nid FROM roomserver_membership" +
+	" WHERE room_nid = $1"
+
+const selectMembershipForUpdateSQL = "" +
+	"SELECT membership_nid FROM roomserver_membership" +
+	" WHERE room_nid = $1 AND target_nid = $2 FOR UPDATE"
+
+const updateMembershipSQL = "" +
+	"UPDATE roomserver_membership SET sender_nid = $3, membership_nid = $4, event_nid = $5" +
+	" WHERE room_nid = $1 AND target_nid = $2"
+
+type membershipStatements struct {
+	insertMembershipStmt                       *sql.Stmt
+	selectMembershipForUpdateStmt              *sql.Stmt
+	selectMembershipFromRoomAndTargetStmt      *sql.Stmt
+	selectMembershipsFromRoomAndMembershipStmt *sql.Stmt
+	selectMembershipsFromRoomStmt              *sql.Stmt
+	updateMembershipStmt                       *sql.Stmt
+}
+
+func (s *membershipStatements) prepare(db *sql.DB) (err error) {
+	_, err = db.Exec(membershipSchema)
+	if err != nil {
+		return
+	}
+
+	return statementList{
+		{&s.insertMembershipStmt, insertMembershipSQL},
+		{&s.selectMembershipForUpdateStmt, selectMembershipForUpdateSQL},
+		{&s.selectMembershipFromRoomAndTargetStmt, selectMembershipFromRoomAndTargetSQL},
+		{&s.selectMembershipsFromRoomAndMembershipStmt, selectMembershipsFromRoomAndMembershipSQL},
+		{&s.selectMembershipsFromRoomStmt, selectMembershipsFromRoomSQL},
+		{&s.updateMembershipStmt, updateMembershipSQL},
+	}.prepare(db)
+}
+
+func (s *membershipStatements) insertMembership(
+	ctx context.Context,
+	txn *sql.Tx, roomNID types.RoomNID, targetUserNID types.EventStateKeyNID,
+) error {
+	stmt := common.TxStmt(txn, s.insertMembershipStmt)
+	_, err := stmt.ExecContext(ctx, roomNID, targetUserNID)
+	return err
+}
+
+func (s *membershipStatements) selectMembershipForUpdate(
+	ctx context.Context,
+	txn *sql.Tx, roomNID types.RoomNID, targetUserNID types.EventStateKeyNID,
+) (membership membershipState, err error) {
+	err = common.TxStmt(txn, s.selectMembershipForUpdateStmt).QueryRowContext(
+		ctx, roomNID, targetUserNID,
+	).Scan(&membership)
+	return
+}
+
+func (s *membershipStatements) selectMembershipFromRoomAndTarget(
+	ctx context.Context,
+	roomNID types.RoomNID, targetUserNID types.EventStateKeyNID,
+) (eventNID types.EventNID, membership membershipState, err error) {
+	err = s.selectMembershipFromRoomAndTargetStmt.QueryRowContext(
+		ctx, roomNID, targetUserNID,
+	).Scan(&membership, &eventNID)
+	return
+}
+
+func (s *membershipStatements) selectMembershipsFromRoom(
+	ctx context.Context, roomNID types.RoomNID,
+) (eventNIDs []types.EventNID, err error) {
+	rows, err := s.selectMembershipsFromRoomStmt.QueryContext(ctx, roomNID)
+	if err != nil {
+		return
+	}
+
+	for rows.Next() {
+		var eNID types.EventNID
+		if err = rows.Scan(&eNID); err != nil {
+			return
+		}
+		eventNIDs = append(eventNIDs, eNID)
+	}
+	return
+}
+func (s *membershipStatements) selectMembershipsFromRoomAndMembership(
+	ctx context.Context,
+	roomNID types.RoomNID, membership membershipState,
+) (eventNIDs []types.EventNID, err error) {
+	stmt := s.selectMembershipsFromRoomAndMembershipStmt
+	rows, err := stmt.QueryContext(ctx, roomNID, membership)
+	if err != nil {
+		return
+	}
+
+	for rows.Next() {
+		var eNID types.EventNID
+		if err = rows.Scan(&eNID); err != nil {
+			return
+		}
+		eventNIDs = append(eventNIDs, eNID)
+	}
+	return
+}
+
+func (s *membershipStatements) updateMembership(
+	ctx context.Context,
+	txn *sql.Tx, roomNID types.RoomNID, targetUserNID types.EventStateKeyNID,
+	senderUserNID types.EventStateKeyNID, membership membershipState,
+	eventNID types.EventNID,
+) error {
+	_, err := common.TxStmt(txn, s.updateMembershipStmt).ExecContext(
+		ctx, roomNID, targetUserNID, senderUserNID, membership, eventNID,
+	)
+	return err
+}