translators/lib/bing.js

Translators is a library which aims to bring free, multiple, enjoyable translation to individuals and students in Nodejs.

"use strict";

const got = require('got');
const cheerio = require('cheerio');
const {
  sleep,
  request_server_region_info,
  check_query_text,
  check_language,
  get_headers
} = require('./common');
const {
  CookieJar
} = require('tough-cookie');
const cookieJar = new CookieJar();
const globalOptions = {
  host_url: null,
  cn_host_url: 'https://cn.bing.com/Translator',
  en_host_url: 'https://www.bing.com/Translator',
  request_server_region_info,
  api_url: null,
  host_headers: null,
  api_headers: null,
  host_info: null,
  tk: null,
  first_time: new Date().getTime(),
  language_map: null,
  query_count: 0,
  output_auto: 'auto-detect',
  output_zh: 'zh-Hans'
};
const get_host_info = host_html => {
  const $ = cheerio.load(host_html);
  let lang_list = $('[id="tta_srcsl"] option[value]') || $('[id="t_srcAllLang"] option[value]');
  lang_list = Array.from(new Set(lang_list.map((idx, item) => {
    return $(item).attr('value');
  }))).sort();
  let language_map = {};
  lang_list.forEach(item => {
    language_map[item] = lang_list;
  });
  let iid = $($('[id="rich_tta"]')).attr('data-iid') + '.' + (globalOptions.query_count + 1);
  let ig = host_html.match('IG:"(.*?)"')[1];
  return {
    'iid': iid,
    'ig': ig,
    'language_map': language_map
  };
};
const get_tk = host_html => {
  let result_str = host_html.match('var params_AbusePreventionHelper = (.*?);')[1];
  let result = eval(result_str);
  return {
    'key': result[0],
    'token': result[1]
  };
};
const bing_api = async (query_text, from_language = 'auto', to_language = 'en', kwargs = {}) => {
  /*
     https://bing.com/Translator, https://cn.bing.com/Translator.
     :param query_text: str, must.
     :param from_language: str, default 'auto'.
     :param to_language: str, default 'en'.
     :param **kwargs:
             :param if_use_cn_host: boolean, default None.
             :param if_ignore_limit_of_length: boolean, default False.
             :param is_detail_result: boolean, default False.
             :param timeout: float, default None.
             :param proxies: dict, default None.
             :param sleep_seconds: float, default `random.random()`.
     :return: str or list
     */
  const {
    if_use_cn_host = null,
    is_detail_result = false,
    timeout = null,
    proxies = null,
    sleep_seconds = parseInt(Math.random() * 10),
    if_ignore_limit_of_length = false
  } = kwargs;
  const use_cn_condition = if_use_cn_host || (await globalOptions.request_server_region_info())['countryCode'] === 'CN';
  globalOptions.host_url = use_cn_condition ? globalOptions.cn_host_url : globalOptions.en_host_url;
  globalOptions.api_url = globalOptions.host_url.replace('Translator', 'ttranslatev3');
  globalOptions.host_headers = get_headers(globalOptions.host_url, {
    if_api: false
  });
  globalOptions.api_headers = get_headers(globalOptions.host_url, {
    if_api: true
  });
  query_text = check_query_text(query_text, if_ignore_limit_of_length);
  let r = await got(globalOptions.host_url, {
    cookieJar,
    headers: globalOptions.host_headers,
    timeout: timeout,
    proxies: proxies
  });
  let host_html = r.body;
  globalOptions.host_info = get_host_info(host_html);
  if (!globalOptions.language_map) {
    globalOptions.language_map = globalOptions.host_info['language_map'];
  }
  let lang = check_language(from_language, to_language, globalOptions.language_map, {
    output_zh: globalOptions.output_zh,
    output_auto: globalOptions.output_auto
  });
  from_language = lang.from_language;
  to_language = lang.to_language;

  // params = {'isVertical': '1', '': '', 'IG': globalOptions.host_info['ig'], 'IID': globalOptions.host_info['iid']}
  globalOptions.api_url = globalOptions.api_url + `?isVertical=1&&IG=${globalOptions.host_info['ig']}&IID=${globalOptions.host_info['iid']}`;
  if (!globalOptions.tk || new Date().getTime() - globalOptions.first_time > 3500) {
    // 3600
    globalOptions.tk = get_tk(host_html);
  }
  let form_data = {
    'text': query_text,
    'fromLang': from_language,
    'to': to_language,
    ...globalOptions.tk
  };
  r = await got.post(globalOptions.api_url, {
    cookieJar,
    headers: globalOptions.api_headers,
    body: form_data,
    form: true,
    timeout: timeout,
    proxies: proxies
  });
  let data = JSON.parse(r.body);
  await sleep(sleep_seconds);
  globalOptions.query_count += 1;
  if (is_detail_result) return data;
  return data[0]['translations'][0]['text'];
};
module.exports = bing_api;