translators/lib/common.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 assert = require('assert');
const _ = require('lodash');
class TranslatorError extends Error {
  constructor(msg) {
    super(msg);
  }
}
const sleep = async seconds => {
  return new Promise(resolve => setTimeout(resolve, seconds * 1000));
};
const debug = str => {
  console.debug(str);
};
const warn = str => {
  console.warn(str);
};
const request_server_region_info = async () => {
  try {
    const {
      body
    } = await got.get('https://httpbin.org/ip', {
      json: true
    });
    const ip_address = body['origin'];
    try {
      const {
        body
      } = await got.get(`http://ip-api.com/json/${ip_address}`, {
        json: true
      }); // http # limit 45 / min.
      let country = body['country'];
      assert(country);
      debug(`Using ${country} server backend.`);
      return body;
    } catch (error) {
      const data = await got.post('https://ip.taobao.com/outGetIpInfo', {
        data: {
          'ip': ip_address,
          'accessKey': 'alibaba_inc'
        }
      });
      return Object.assign(data, {
        'countryCode': data.get('country_id')
      });
    }
  } catch (error) {
    throw new TranslatorError('Unable to find server backend.');
  }
};
const check_query_text = (query_text, {
  if_ignore_limit_of_length = false,
  limit_of_length = 5000
}) => {
  query_text = query_text.trim();
  if (query_text.length === 0) return '';
  let length = query_text.length;
  if (length >= limit_of_length && !if_ignore_limit_of_length) {
    throw new TranslatorError('The length of the text to be translated exceeds the limit.');
  } else {
    if (length >= limit_of_length) {
      warn(`The translation ignored the excess[above ${limit_of_length}]. Length of query_text is ${length}.`);
      warn('The translation result will be incomplete.');
      return query_text.substr(0, limit_of_length - 1);
    }
  }
  return query_text;
};
const check_language = (from_language, to_language, language_map, {
  output_zh = null,
  output_auto = 'auto'
}) => {
  const auto_pool = ['auto', 'auto-detect'];
  const zh_pool = ['zh', 'zh-CN', 'zh-CHS', 'zh-Hans'];
  from_language = auto_pool.indexOf(from_language) >= 0 ? output_auto : from_language;
  from_language = output_zh && zh_pool.indexOf(from_language) >= 0 ? output_zh : from_language;
  to_language = output_zh && zh_pool.indexOf(to_language) >= 0 ? output_zh : to_language;
  if (from_language != output_auto && !_.has(language_map, from_language)) {
    throw new TranslatorError(`Unsupported from_language[${from_language}] in ${Object.keys(language_map).sort()}.`);
  } else if (!_.has(language_map, to_language)) {
    throw new TranslatorError(`Unsupported to_language[${to_language}] in ${Object.keys(language_map).sort()}.`);
  } else if (from_language != output_auto && language_map[from_language].indexOf(to_language) < 0) {
    throw new TranslatorError(`Unsupported translation: from [${from_language}] to [${to_language}]!`);
  }
  return {
    from_language,
    to_language
  };
};
const get_headers = (host_url, {
  if_api = false,
  if_referer_for_host = true,
  if_ajax_for_api = true,
  if_json_for_api = false
}) => {
  const url = new URL(host_url);
  const user_agent = 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.71 Safari/537.36';
  let host_headers = {
    'Origin': url.origin,
    [if_referer_for_host ? 'Referer' : 'Host']: host_url,
    'User-Agent': user_agent
  };
  let api_headers = {
    'Host': url.hostname,
    'Origin': url.origin,
    'Referer': host_url,
    'X-Requested-With': 'XMLHttpRequest',
    'Content-Type': 'application/x-www-form-urlencoded; charset=UTF-8',
    'User-Agent': user_agent
  };
  if (if_api && !if_ajax_for_api) {
    api_headers.remove('X-Requested-With');
    api_headers['Content-Type'] = 'text/plain';
  }
  if (if_api && if_json_for_api) {
    api_headers['Content-Type'] = 'application/json';
  }
  return !if_api ? host_headers : api_headers;
};
module.exports = {
  sleep,
  warn,
  request_server_region_info,
  check_query_text,
  check_language,
  get_headers,
  TranslatorError
};