Remove rooms table from federation sender (#1751)

* Remove last sent event ID column from federation sender

* Remove EventIDMismatchError

* Remove the federationsender rooms table altogether, it's useless

* Add migration

* Fix migrations

* Fix migrations

federationsender/storage/postgres/deltas/2021020411080000_rooms.go

@@ -0,0 +1,46 @@
+// Copyright 2021 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 deltas
+
+import (
+	"database/sql"
+	"fmt"
+
+	"github.com/matrix-org/dendrite/internal/sqlutil"
+	"github.com/pressly/goose"
+)
+
+func LoadFromGoose() {
+	goose.AddMigration(UpRemoveRoomsTable, DownRemoveRoomsTable)
+}
+
+func LoadRemoveRoomsTable(m *sqlutil.Migrations) {
+	m.AddMigration(UpRemoveRoomsTable, DownRemoveRoomsTable)
+}
+
+func UpRemoveRoomsTable(tx *sql.Tx) error {
+	_, err := tx.Exec(`
+		DROP TABLE IF EXISTS federationsender_rooms;
+	`)
+	if err != nil {
+		return fmt.Errorf("failed to execute upgrade: %w", err)
+	}
+	return nil
+}
+
+func DownRemoveRoomsTable(tx *sql.Tx) error {
+	// We can't reverse this.
+	return nil
+}