Node Slack SDK Issue 252 Experiment

.dockerignore

node_modules
.git
memstats

.gitignore

node_modules
teams.csv
*.log

README.md

Node Slack SDK Issue 252 Experiment

Setup

1. Create a teams.csv file with the teams you will connect to. The goal is to have 1000 connections, so I used 100 teams and an xoxp token for each team. Then in the code there is a for loop that makes 10 connections per team. You can adjust that factor according to your goals. Use teams.csv.sample as a template.

2. npm install

Running the test

node index.js.

You will start to see log statements about connections being connected and disconnected. Once the connections seem stable (no more log statements for ~10 seconds) make sure at least one GC occurs (a log statement that says stats received), and then toggle your connection state. That means if you started the test with your network connection on, turn it off, and vice versa.

Results

The results will be written to a timestamped csv file beginning with memstats-. The most interesting column in this file will be estimated_base. You can visualize the results in a spreadsheet.

Note that each of the stats received log statements correspond to one row in the results file. In order to interpret when certain network connection changes occurred, you can count the number of those messages before each toggle and then find them in the results. The last two columns, clients_connected and clients_reconnecting, tell you how many of the connections were either connected or disconnected, respectively.

Docker Stuff

I did at some point run this in a container but then I realized I didn't need to, so I stopped looking at it. It may or may not work, so don't trust it.

Dockerfile

FROM node:boron
MAINTAINER Ankur Oberoi <aoberoi@gmail.com>

RUN mkdir -p /usr/src/app
WORKDIR /usr/src/app

COPY package.json /usr/src/app/
RUN npm install

COPY . /usr/src/app

RUN groupadd -r app && useradd -r -g app app
USER app

CMD ["node", "index.js"]

index.js

const RtmClient = require('@slack/client').RtmClient;
const CLIENT_EVENTS = require('@slack/client').CLIENT_EVENTS;
const fs = require('fs');
const parse = require('csv-parse/lib/sync');
const memwatch = require('memwatch-next');

const resultsFilename = `./memstats-${Date.now()}.csv`;
const teamsFileContents = fs.readFileSync('./teams.csv', 'utf8');
const teams = parse(teamsFileContents, { columns: true });

const clients = [];
let nextClientNum = 0;
function createClient(team) {
  const rtm = new RtmClient(team.member_xoxp_token, {
    slackAPIUrl: 'https://qa.slack.com/api/',
    // Uncomment to run test with no MemoryDataStore
    // dataStore: null,
  });
  const clientInfo = {
    clientNum: nextClientNum,
    rtm,
    connected: false,
  };
  nextClientNum += 1;

  rtm.on(CLIENT_EVENTS.RTM.RTM_CONNECTION_OPENED, () => {
    console.log(`client ${clientInfo.clientNum} connected`);
    clientInfo.connected = true;
  });

  rtm.on(CLIENT_EVENTS.RTM.ATTEMPTING_RECONNECT, () => {
    console.log(`client ${clientInfo.clientNum} reconnecting`);
    clientInfo.connected = false;
  });

  rtm.start();
  clients.push(clientInfo);
}

for (let i = 0; i < teams.length; i++) {
  for (let j = 0; j < 10; j++) {
    createClient(teams[i]);
  }
}

memwatch.on('leak', (info) => {
  console.warn('leak detected');
  console.dir(info);
  // Uncomment to insert leak info into results file
  // fs.appendFile(resultsFilename, JSON.stringify(info) + '\n');
});

let firstLine = true;
memwatch.on('stats', (stats) => {
  console.log('stats received');
  let info = [];
  if (firstLine) {
    info.push('num_full_gc');
    info.push('num_inc_gc');
    info.push('heap_compactions');
    info.push('usage_trend');
    info.push('estimated_base');
    info.push('current_base');
    info.push('min');
    info.push('max');
    info.push('clients_connected');
    info.push('clients_reconnecting');
    fs.appendFileSync(resultsFilename, info.join(',') + '\n');
    info = [];
    firstLine = false;
  }

  info.push(stats['num_full_gc']);
  info.push(stats['num_inc_gc']);
  info.push(stats['heap_compactions']);
  info.push(stats['usage_trend']);
  info.push(stats['estimated_base']);
  info.push(stats['current_base']);
  info.push(stats['min']);
  info.push(stats['max']);
  info.push(clients.filter(c => c.connected).length);
  info.push(clients.filter(c => !c.connected).length);

  fs.appendFile(resultsFilename, info.join(',') + '\n');
});

package.json

{
  "name": "node-slack-sdk-252",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "start": "node index.js"
  },
  "author": "",
  "license": "ISC",
  "dependencies": {
    "@slack/client": "^3.6.0",
    "csv-parse": "^1.1.7",
    "memwatch-next": "^0.3.0"
  }
}

teams.csv.sample

team_id,member_xoxp_token