class DatabaseError extends Error {
  constructor(message, code) {
    super(message);
    this.name = "DatabaseError";
    this.code = code;
  }
}

class ConnectionError extends DatabaseError {
  constructor(host) {
    super(`Failed to connect to ${host}`, 503);
    this.name = "ConnectionError";
    this.host = host;
  }
}

const err = new ConnectionError("db.server.io");

console.log([
  err instanceof ConnectionError,
  err instanceof DatabaseError,
  err instanceof Error,
  err.name,
  err.code,
  err.message,
].join(" | "));