json.ts

/**
 * @license
 * Copyright 2017 Google LLC
 *
 * 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.
 */
import { isNonArrayObject } from './type';

/**
 * Returns the Object resulting from parsing the given JSON, or null if the
 * given string does not represent a JSON object.
 */
export function jsonObjectOrNull(
  s: string
): { [name: string]: unknown } | null {
  let obj;
  try {
    obj = JSON.parse(s);
  } catch (e) {
    return null;
  }
  if (isNonArrayObject(obj)) {
    return obj;
  } else {
    return null;
  }
}