packages/runtime/src/runtime-snapshot.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.
 */

/** Clone plain request data and freeze every cloned container at an ownership boundary. */
export function cloneAndFreezeRuntimeSnapshot<T>(value: T): T {
  if (Array.isArray(value)) {
    return Object.freeze(value.map((item) => cloneAndFreezeRuntimeSnapshot(item))) as T;
  }
  if (value && typeof value === 'object') {
    const prototype = Object.getPrototypeOf(value);
    if (prototype !== Object.prototype && prototype !== null) return value;
    const clone: Record<string, unknown> = Object.create(prototype);
    for (const key of Object.keys(value)) {
      const descriptor = Object.getOwnPropertyDescriptor(value, key);
      if (!descriptor || !('value' in descriptor)) {
        throw new Error(`Runtime snapshot rejects accessor property ${key}`);
      }
      clone[key] = cloneAndFreezeRuntimeSnapshot(descriptor.value);
    }
    return Object.freeze(clone) as T;
  }
  return value;
}