slack message exporter

exporter.js

/*
    this is free software: you can redistribute it and/or modify
    it under the terms of the GNU Lesser General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.
    it is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Lesser General Public License for more details.
    see <http://www.gnu.org/licenses/>.
*/
/**
 * @file exporter.js
 * @author:
 *   Simon Jentzsch <simon.jentzsch@slock.it>
 * @date 2016
 */
'use strict';

var _     = require("underscore");
var fs    = require("fs");
var Slack = require('slack-api');
var token = "YOUR-TOKEN";  // put your token here!

Slack.users.list({token:token}, function (error, data) {

  // create a map with the real usernames
  var users = {};
  data.members.forEach(function(u) {
     users[u.id]=u.profile.real_name+" ( "+u.name+")";
  });

  exportAllChannels(users);

});

function timestamp(ts) {
   var p = ts.indexOf(".");
   var v = new Date(1000 * parseInt(p<0?ts:ts.substr(0,p))).toUTCString();
   return v.substring(5, v.indexOf("GMT")-4);
}

function exportGroup(group, users, api) {
   // name of the current channel ( I added a # for public and a _ for private )
   var name = (group.is_channel ? "#" : "_") + group.name;
   
   // get the last 1000 messages
   api.history({token:token, channel: group.id , count: 1000 }, function (error, slackdata) {
      var archFile = "archive/"+name+".json";  // file for json-storage
      fs.readFile(archFile, function (err, data) {
        var exists = {}, msgs = [], newEntries = false;
        if (!err && data) {
            // parse existing data and use the timestamp as id
            msgs = JSON.parse(data);
            msgs.forEach(function(m){    exists[m.ts]=m;    });
        }
        
        // for all data, we don't already have we insert them.
        slackdata.messages.forEach(function(m) {
           if (!exists[m.ts]) {
              msgs.splice(0,0,m);
              newEntries=true;
           }
        });

        // sort the messages by timestamp
        msgs = _.sortBy(msgs, function(m) { return 0 - parseFloat(m.ts); });

        // export the archive
        fs.writeFile(archFile ,JSON.stringify(msgs));

        if (!newEntries) return;

        // create a easy to read text-file
        var all = "";
        msgs.forEach(function(msg) {
          if (msg.type!="message") return;
          all="#"+timestamp(msg.ts)+"   "+(users[msg.user] || msg.user) + "\n"+msg.text+"\n\n"+all;
        });
        fs.writeFile("txt/"+name+".txt" ,all);
        
      });
   });
}

function exportAllChannels(users) {

   // export private channels
   Slack.groups.list({token:token}, function (error, data) {
     data.groups.forEach(function(g)  {  exportGroup(g,users,Slack.groups);});
   });
   
   // export the public channels
   Slack.channel.list({token:token}, function (error, data) {
     data.channels.forEach(function(g) {  exportGroup(g,users,Slack.channel);  });
   });
}

package.json

{
  "name": "slack",
  "version": "0.1.0",
  "description": "exports all messages",
  "homepage": "http://slock.it",
  "main": "exporter.js",
  "dependencies": {
    "slack-api": "^0.1.11",
    "underscore": "^1.8.3"
  },
  "devDependencies": {},
  "keywords": [],
  "author": "slockt.it",
  "license": "MIT"
}