slack-translator-bot.js

// inspired from:
// https://gist.github.com/masuidrive/0bea937bcaf12bc94e7fba8acf13382a

// ## Go to https://api.slack.com/
// * Create your app.
// * Create "Bot User".
// * Go to "OAuth Tokens & Redirect URLs" and copy the Access Token.
// * Set the permission of "chat:write:bot" to the bot.

// ## Go to https://www.google.com/script/start/
// * Install a library: https://github.com/soundTricker/SlackApp
// * Create your script and paste this script.
// * Paste the slack Access Token.
// * Publish as a web application and copy the URL.

// ## Go to https://api.slack.com/
// * Set the URL of the script.

var slack_token = 'xoxp-YOUR TOKEN HERE';

function translateText(text) {
  var translatedText = LanguageApp.translate(text, "ja", "en");
  translatedText = translatedText.replace(/<@\s+/g, '<@'); // username
  translatedText = translatedText.replace(/:\s(\w+?):/g, ':$1:'); // emoji
  translatedText = translatedText.replace(/<#\s+(\w+?)\s+\|\s+(\w+?)>/g, '<#$1|$2>'); // channel
  return translatedText;
}

function post_to_slack(channel, message, thread_ts) {
  var slackApp = SlackApp.create(slack_token);  
  var options = {link_names: true};
  if (thread_ts) {
    options["thread_ts"] = thread_ts;
  }
  slackApp.chatPostMessage(channel, message, options);
}

function doPost(e) {
  var params = JSON.parse(e.postData.getDataAsString());
  Logger.log(params);
  
  var res = ContentService.createTextOutput();
  res.setMimeType(ContentService.MimeType.JSON);
  
  // challenge
  if (params.type == "url_verification") { 
    res.setContent(JSON.stringify(params));
    return res;
  }
  
  var ev = params.event;
  if (ev.type == "app_mention") {
    var originalText = ev.text;
    params.authed_users.forEach(function(user){
      originalText = originalText.replace("<@" + user + ">", '')
    });
    var translatedText = translateText(originalText);
    post_to_slack(ev.channel, translatedText, ev.thread_ts);
  }
  
  return ""; // FIXME
}