botlib/proto_to_json.js

/**
 * Copyright 2019 Google Inc. All Rights Reserved.
 *
 * 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.
 */

/**
 * @fileoverview Utilities for converting from goog.protobuf.Struct proto to
 * JSON.
 */

const JSON_SIMPLE_VALUE_KINDS =
    new Set(['numberValue', 'stringValue', 'boolValue']);

function structProtoToJson(proto) {
  if (!proto || !proto.fields) {
    return {};
  }
  const json = {};
  for (const field in proto.fields) {
    json[field] = valueProtoToJson(proto.fields[field]);
  }
  return json;
}

function valueProtoToJson(proto) {
  if (!proto || !proto.kind) {
    return null;
  }

  if (JSON_SIMPLE_VALUE_KINDS.has(proto.kind)) {
    return proto[proto.kind];
  } else if (proto.kind === 'nullValue') {
    return null;
  } else if (proto.kind === 'listValue') {
    if (!proto.listValue || !proto.listValue.values) {
      console.warn('Invalid JSON list value proto: ', JSON.stringify(proto));
    }
    return proto.listValue.values.map(valueProtoToJson);
  } else if (proto.kind === 'structValue') {
    return structProtoToJson(proto.structValue);
  } else {
    console.warn('Unsupported JSON value proto kind: ', proto.kind);
    return null;
  }
}

module.exports = {
  structProtoToJson
};