Add room ID storage

src/github.com/matrix-org/dendrite/roomserver/storage/sql.go

@@ -12,6 +12,8 @@ type statements struct {
 	selectEventTypeNIDStmt     *sql.Stmt
 	insertEventStateKeyNIDStmt *sql.Stmt
 	selectEventStateKeyNIDStmt *sql.Stmt
+	insertRoomNIDStmt          *sql.Stmt
+	selectRoomNIDStmt          *sql.Stmt
 }
 
 func (s *statements) prepare(db *sql.DB) error {
@@ -29,6 +31,10 @@ func (s *statements) prepare(db *sql.DB) error {
 		return err
 	}
 
+	if err = s.prepareRooms(db); err != nil {
+		return err
+	}
+
 	return nil
 }
 
@@ -226,3 +232,54 @@ func (s *statements) selectEventStateKeyNID(eventStateKey string) (eventStateKey
 	}
 	return
 }
+
+func (s *statements) prepareRooms(db *sql.DB) (err error) {
+	_, err = db.Exec(roomsSchema)
+	if err != nil {
+		return
+	}
+	if s.insertRoomNIDStmt, err = db.Prepare(insertRoomNIDSQL); err != nil {
+		return
+	}
+	if s.selectRoomNIDStmt, err = db.Prepare(selectRoomNIDSQL); err != nil {
+		return
+	}
+	return
+}
+
+const roomsSchema = `
+CREATE SEQUENCE IF NOT EXISTS room_nid_seq;
+CREATE TABLE rooms (
+    -- Local numeric ID for the room.
+    room_nid BIGINT PRIMARY KEY DEFAULT nextvalue('room_nid_seq'),
+    -- Textual ID for the room.
+    room_id TEXT NOT NULL CONSTRAINT room_id_unique UNIQUE
+);
+`
+
+const insertRoomNIDSQL = "" +
+	"INSERT INTO rooms (room_id) VALUES ($1)" +
+	" ON CONFLICT ON CONSTRAINT room_id_unique" +
+	" DO UPDATE SET room_id = $1" +
+	" RETURNING (room_nid)"
+
+const selectRoomNIDSQL = "" +
+	"SELECT room_nid FROM rooms WHERE room_id = $1"
+
+func (s *statements) insertRoomNID(roomID string) (roomNID int64, err error) {
+	err = s.insertRoomNIDStmt.QueryRow(roomID).Scan(&roomNID)
+	if err == sql.ErrNoRows {
+		roomNID = 0
+		err = nil
+	}
+	return
+}
+
+func (s *statements) selectRoomNID(roomID string) (roomNID int64, err error) {
+	err = s.selectRoomNIDStmt.QueryRow(roomID).Scan(&roomNID)
+	if err == sql.ErrNoRows {
+		roomNID = 0
+		err = nil
+	}
+	return
+}