slackClient.js

const fs = require('fs');
const request = require('request');
const WebSocket = require('ws');
const HttpsProxyAgent = require('https-proxy-agent');

const TOKEN = process.env.SLACK_TOKEN;
const HTTP_PROXY = process.env.HTTP_PROXY;
const PROXY = process.env.PROXY;

if (TOKEN === undefined) {
  console.log(
    // eslint-disable-line no-console
    'Error: SLACK_TOKEN undefined. Please add SLACK_TOKEN to the environment variables.'
  );
  process.exit(1);
}

const proxyUrl = url => {
  return url.replace('wss://cerberus-xxxx.lb.slack-msgs.com', `ws://${PROXY}`);
};

// makes a request to slack. Adds token to query
function slackRequest(endpoint, query, callback) {
  const qs = query;
  qs.token = TOKEN;
  request.get(
    {
      url: `http://${PROXY}/api/${endpoint}`,
      qs
    },
    (error, response, data) => {
      if (error) {
        fs.writeFileSync('error_log.txt', error);
        process.exit(1);
      }

      if (response.statusCode !== 200) {
        fs.writeFileSync(
          'error_log.txt',
          `Response Error: ${response.statusCode}`
        );
        process.exit(1);
      }

      const parsedData = JSON.parse(data);
      if (!parsedData.ok) {
        // can't see console.logs with blessed
        fs.writeFileSync('error_log.txt', `Error: ${parsedData.error}`);
        process.exit(1);
      }

      if (callback) {
        callback(error, response, data);
      }
    }
  );
}

module.exports = {
  init(callback) {
    slackRequest('rtm.start', {}, (error, response, data) => {
      const parsedData = JSON.parse(data);
      try {
        const ws = new WebSocket(proxyUrl(parsedData.url), {
          agent: new HttpsProxyAgent(HTTP_PROXY)
        });
        callback(parsedData, ws);
      } catch (e) {
        fs.writeFileSync('error_log.txt', parsedData.url);
        process.exit(1);
      }
    });
  },
  getChannels(callback) {
    slackRequest('channels.list', {}, (error, response, data) => {
      if (callback) {
        callback(error, response, data);
      }
    });
  },
  joinChannel(name, callback) {
    slackRequest(
      'channels.join',
      {
        name
      },
      (error, response, data) => {
        if (callback) {
          callback(error, response, data);
        }
      }
    );
  },
  getChannelHistory(id, callback) {
    slackRequest(
      'channels.history',
      {
        channel: id
      },
      (error, response, data) => {
        if (callback) {
          callback(error, response, data);
        }
      }
    );
  },
  markChannel(id, timestamp, callback) {
    slackRequest(
      'channels.mark',
      {
        channel: id,
        ts: timestamp
      },
      (error, response, data) => {
        if (callback) {
          callback(error, response, data);
        }
      }
    );
  },
  getUsers(callback) {
    slackRequest('users.list', {}, (error, response, data) => {
      if (callback) {
        callback(error, response, data);
      }
    });
  },
  openIm(id, callback) {
    slackRequest(
      'im.open',
      {
        user: id
      },
      (error, response, data) => {
        if (callback) {
          callback(error, response, data);
        }
      }
    );
  },
  getImHistory(id, callback) {
    slackRequest(
      'im.history',
      {
        channel: id
      },
      (error, response, data) => {
        if (callback) {
          callback(error, response, data);
        }
      }
    );
  },
  markIm(id, timestamp, callback) {
    slackRequest(
      'im.mark',
      {
        channel: id,
        ts: timestamp
      },
      (error, response, data) => {
        if (callback) {
          callback(error, response, data);
        }
      }
    );
  }
};