Hodor

Hodor is a an automation application that is used to open the door controlled by an intercom system from Slack using a custom slash command.

How it Works

Once a command /door open is sent from slack, it is processed by the slack bot service and validated before triggering the door_service to activate the switch on the intercom system through the relay.

Wiring the Hardware

We imitate a button press on the intercom by short-circuiting the physical button on the intercom. This is done by using a simple relay which is controlled by the Raspberry Pi as shown in the figure.

Components

• door_service(nodejs_rpi): Raspberry Pi running a Node.js server that is connected to the intercom switch using a relay.
• slack_bot: Slack integration with a custom slash command /door which is handled by a serverless Python web service running on AWS Lambda

How to Run?

Door Service

$ npm install 
$ node app.js

Deployment

If the server is run on port 80 of Raspberry Pi, it can be available on the internet using Dataplicity.

Cron jobs can be added to automatically restart the service on restart of the device.

@reboot /path/to/node /path/to/the/app.js &

Slack Bot

$ export VERIFICATION_TOKEN=<Verification Token for App from Slack>
$ export CHANNEL_ID=<Identifier for the Slack Channel in which command should be accessible>
$ export DOOR_SERVICE=<URL end point for the Node.js server running on Raspberry Pi>
$ pip install -r requirements.txt
$ python slack_bot.py

Deployment to AWS Lambda

$ zappa init
$ zappa deploy

Note: Your AWS credentials need to be configured for Zappa to work.