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sige for ConfigCat

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Complete guide to build a Slack Chatbot in 7 minutes and host it for free

Based on GitHub's Hubot. Connected to Slack. Deployed to Heroku.

I have a thing for robots and wanted to build a chatbot as an experiment that calls my service's ( \health endpoint and returns if everything is okay. It took me quite a long time to go trough the possible frameworks and docs, read all the outdated guides to find the quickest and cheapest way. I feel like it might worth sharing.

The tools needed:

Adding Hubot integration to your Slack Workspace

Find Hubot in Slack App Directory

Connect to Workspace



Take a note of the API Token, you'll need it later


Running Hubot on local machine

Install Yeoman and Hubot generator

npm install -g yo generator-hubot

Scaffold a Hubot project

mkdir catbot
cd catbot
yo hubot --adapter=slack

Start Hubot using API Token

HUBOT_SLACK_TOKEN=xoxb-271695489427-739714865891-Z5gPPiuTORKDFO4QvqKe1B9y ./bin/hubot --adapter slack

Open Slack and start a conversation

The chatbot should be available under Apps.


Test with help command


Recognizing health command

And make a HTTP GET call to ConfigCat's /health endpoint and reply back the results via Slack.

I created a under /scripts folder with the following code:

module.exports = (robot) ->
    robot.hear /health/i, (reply) ->
        .get() (err, res, body) ->
            reply.send body

See the complete source code on GitHub.

I used CoffeeScript because I like to experiment and it feels fancy. But you can use JavaScript as well.

Test if the health check works


Deploying to Heroku

Check Node.js version

node --version

Open package.json and check Node.js version. In my case the generated package.json was "node": "0.10.x" so I changed it to:

"engines": {
  "node": "10.16"

Git commit

Make sure you’ve created a git repository, and that your work is committed.

git init
git add .
git commit -m "Initial commit"

Heroku CLI

Install the Heroku CLI. then log in.

heroku login

Create app.

heroku create

Set environment variable for API Token.

heroku config:set HUBOT_SLACK_TOKEN=xoxb-271695489427-739714865891-Z5gPPiuTORKDFO4QvqKe1B9yt --app=arcane-dusk-29327

Git push

git push heroku master

Avoiding sleep mode

Since I'm using Heroku's free plan, the app will eventually go to sleep mode. To avoid that add hubot-eroku-keepalive script to your chatbot.

Reference docs

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