packages/runtime-host/src/protocol/websocket-path.ts

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.
 */

export const RUNTIME_HOST_WEBSOCKET_PATH_MAX_BYTES = 1_000;

export function isCanonicalRuntimeHostWebSocketPath(value: unknown): value is string {
  if (
    typeof value !== 'string' ||
    !value.startsWith('/') ||
    new TextEncoder().encode(value).byteLength > RUNTIME_HOST_WEBSOCKET_PATH_MAX_BYTES ||
    /[\u0000-\u001f\u007f]/u.test(value)
  ) {
    return false;
  }
  try {
    const url = new URL(value, 'ws://runtime-host.invalid');
    return url.origin === 'ws://runtime-host.invalid' && url.pathname === value && !url.search;
  } catch {
    return false;
  }
}