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

federationsender/storage/postgres/joined_hosts_table.go

@@ -0,0 +1,136 @@
+// 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/lib/pq"
+	"github.com/matrix-org/dendrite/common"
+	"github.com/matrix-org/dendrite/federationsender/types"
+	"github.com/matrix-org/gomatrixserverlib"
+)
+
+const joinedHostsSchema = `
+-- The joined_hosts table stores a list of m.room.member event ids in the
+-- current state for each room where the membership is "join".
+-- There will be an entry for every user that is joined to the room.
+CREATE TABLE IF NOT EXISTS federationsender_joined_hosts (
+    -- The string ID of the room.
+    room_id TEXT NOT NULL,
+    -- The event ID of the m.room.member join event.
+    event_id TEXT NOT NULL,
+    -- The domain part of the user ID the m.room.member event is for.
+    server_name TEXT NOT NULL
+);
+
+CREATE UNIQUE INDEX IF NOT EXISTS federatonsender_joined_hosts_event_id_idx
+    ON federationsender_joined_hosts (event_id);
+
+CREATE INDEX IF NOT EXISTS federatonsender_joined_hosts_room_id_idx
+    ON federationsender_joined_hosts (room_id)
+`
+
+const insertJoinedHostsSQL = "" +
+	"INSERT INTO federationsender_joined_hosts (room_id, event_id, server_name)" +
+	" VALUES ($1, $2, $3)"
+
+const deleteJoinedHostsSQL = "" +
+	"DELETE FROM federationsender_joined_hosts WHERE event_id = ANY($1)"
+
+const selectJoinedHostsSQL = "" +
+	"SELECT event_id, server_name FROM federationsender_joined_hosts" +
+	" WHERE room_id = $1"
+
+type joinedHostsStatements struct {
+	insertJoinedHostsStmt *sql.Stmt
+	deleteJoinedHostsStmt *sql.Stmt
+	selectJoinedHostsStmt *sql.Stmt
+}
+
+func (s *joinedHostsStatements) prepare(db *sql.DB) (err error) {
+	_, err = db.Exec(joinedHostsSchema)
+	if err != nil {
+		return
+	}
+	if s.insertJoinedHostsStmt, err = db.Prepare(insertJoinedHostsSQL); err != nil {
+		return
+	}
+	if s.deleteJoinedHostsStmt, err = db.Prepare(deleteJoinedHostsSQL); err != nil {
+		return
+	}
+	if s.selectJoinedHostsStmt, err = db.Prepare(selectJoinedHostsSQL); err != nil {
+		return
+	}
+	return
+}
+
+func (s *joinedHostsStatements) insertJoinedHosts(
+	ctx context.Context,
+	txn *sql.Tx,
+	roomID, eventID string,
+	serverName gomatrixserverlib.ServerName,
+) error {
+	stmt := common.TxStmt(txn, s.insertJoinedHostsStmt)
+	_, err := stmt.ExecContext(ctx, roomID, eventID, serverName)
+	return err
+}
+
+func (s *joinedHostsStatements) deleteJoinedHosts(
+	ctx context.Context, txn *sql.Tx, eventIDs []string,
+) error {
+	stmt := common.TxStmt(txn, s.deleteJoinedHostsStmt)
+	_, err := stmt.ExecContext(ctx, pq.StringArray(eventIDs))
+	return err
+}
+
+func (s *joinedHostsStatements) selectJoinedHostsWithTx(
+	ctx context.Context, txn *sql.Tx, roomID string,
+) ([]types.JoinedHost, error) {
+	stmt := common.TxStmt(txn, s.selectJoinedHostsStmt)
+	return joinedHostsFromStmt(ctx, stmt, roomID)
+}
+
+func (s *joinedHostsStatements) selectJoinedHosts(
+	ctx context.Context, roomID string,
+) ([]types.JoinedHost, error) {
+	return joinedHostsFromStmt(ctx, s.selectJoinedHostsStmt, roomID)
+}
+
+func joinedHostsFromStmt(
+	ctx context.Context, stmt *sql.Stmt, roomID string,
+) ([]types.JoinedHost, error) {
+	rows, err := stmt.QueryContext(ctx, roomID)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close() // nolint: errcheck
+
+	var result []types.JoinedHost
+	for rows.Next() {
+		var eventID, serverName string
+		if err = rows.Scan(&eventID, &serverName); err != nil {
+			return nil, err
+		}
+		result = append(result, types.JoinedHost{
+			MemberEventID: eventID,
+			ServerName:    gomatrixserverlib.ServerName(serverName),
+		})
+	}
+
+	return result, nil
+}