lila/bin/send-lichobile-upgrade.js

import { MongoClient } from 'mongodb';

const oauthToken = process.env.OAUTH_TOKEN;
const client = new MongoClient('mongodb://127.0.0.1:27917/lichess');
const lichessUrl = 'http://l.org';
const dryRun = true;

// hardcode translations here
const translations = {
  en: `Upgrade to our new app: https://lichess.org/app`,
};

const count = client.db().collection('lm_user_recent_nomobile').estimatedDocumentCount();

console.log(`Sending messages to ${count} users...`);

const chunkSize = 100;
const chunk = [];

client.db().collection('lm_user_recent_nomobile').find().forEach(user => {
  // group by chunks of 100 users
  chunk.push(user._id);
  if (chunk.length >= chunkSize) processChunk();
});

function processChunk() {

  const users = db.user4.find({ _id: { $in: chunk } },{$project:{lang:1}}).toArray();

  if (dryRun) console.log(users.map(u => `${u._id} (${u.lang})`).join('\n'));
  else {
    const res = await fetch(`${lichessUrl}/inbox/${username}`, {
      method: 'POST',
      headers: {
        'Content-Type': 'application/x-www-form-urlencoded',
        Authorization: `Bearer ${oauthToken}`,
      },
      body: new URLSearchParams({ text }),
    });

    if (!res.ok) console.error(`Failed to send message to ${username}: ${res.status} ${res.statusText}`);
  }

  await new Promise(resolve => setTimeout(resolve, 500)); // Avoid hitting rate limits
});

function makeMessage(langCode, url) {
  const lang = langCode.slice(0, 2);
  const translated = translations[lang] || translations.en;
  return translated.replace('{URL}', url);
}