ln-telegram/post/post_nodes_offline.js

Lightning Network Telegram bot commands

const asyncAuto = require('async/auto');
const {returnResult} = require('asyncjs-util');

const {icons} = require('./../interface');

const escape = text => text.replace(/[_*[\]()~`>#+\-=|{}.!\\]/g, '\\\$&');
const {isArray} = Array;
const markup = {parse_mode: 'MarkdownV2'};
const shortId = id => id.slice(0, 8);

/** Post that nodes have gone offline

  {
    bot: <Telegram Bot Object>
    [connected]: <Connected User Id>
    offline: [{
      alias: <Node Alias String>
      id: <Node Identity Public Key Hex String>
    }]
  }

  @returns via cbk or Promise
*/
module.exports = ({bot, connected, offline}, cbk) => {
  return new Promise((resolve, reject) => {
    return asyncAuto({
      // Check arguments
      validate: cbk => {
        if (!bot) {
          return cbk([400, 'ExpectedTelegramBotToPostNodesOffline']);
        }

        if (!isArray(offline)) {
          return cbk([400, 'ExpectedArrayOfOfflineNodesToPostNodesOffline']);
        }

        return cbk();
      },

      // Setup the message to send notifying that nodes are offline
      message: ['validate', ({}, cbk) => {
        // Exit early when there is no connected user to message
        if (!connected) {
          return cbk();
        }

        // Exit early when no nodes went offline
        if (!offline.length) {
          return cbk();
        }

        const aliases = offline.map(n => `${n.alias} ${shortId(n.id)}`.trim());
        const event = `${icons.disconnected} Lost connection!`

        const details = `Cannot connect to ${aliases}.`;

        return cbk(null, `_${escape(event)} ${escape(details)}_`);
      }],

      // Send the message
      send: ['message', async ({message}) => {
        if (!message) {
          return;
        }

        return await bot.api.sendMessage(connected, message, markup);
      }],
    },
    returnResult({reject, resolve, of: 'message'}, cbk));
  });
};