Publish dash button presses to a MQTT broker. 🔘📡

Based on node-dash-button by Alex Hortin - all credits belong to him.

Tested on macOS and Linux. If you're running on Linux you have to install libpcap-dev:

• Ubuntu, Debian, Raspbian, ... $ sudo apt-get install libpcap-dev
• Fedora, CentOS $ sudo yum install libpcap-devel

Prerequisite: Node.js version 6.0 or above. I suggest to use https://github.com/tj/n to install a recent version of Node.js.

$ sudo npm install -g dashbutton2mqtt

$ sudo dashbutton2mqtt --scan

The scan shows only MAC Addresses that are known to be registered by Amazon. If you want to see all detected addresses add the option -v debug.

Create a JSON file that maps dash button mac addresses to MQTT topics and payloads.

Example:

{ "50:f5:da:60:20:10": { "topic": "dashbutton/foo" }, "50:f5:da:60:20:11": { "topic": "dashbutton/bar", "payload": "press" } }

If you omit the payload attribute an empty string will be published.

$ sudo dashbutton2mqtt -m /path/to/mapping.json

• Since node-dash-button uses libpcap to scan for dash button arp packets this tool must be run with superuser.
• This tool has to be executed on a host that is connected to the same wifi network as the dash buttons.
• Due to the nature of the dash buttons there will be a latency of ~4 seconds between a button press and the MQTT publish.
• As long as the LED of the dash button is blinking you can't do further button presses.

By default this tool binds to the first network interface. To bind to a specific interface, such as eth1, pass the name of the interface with the --interface option.

If multiple presses are detected you can increase the timeout between presses. Default is 5000ms, depending on your network this may not be enough, you can set a higher timeout with the --timeout option.

Usage: dashbutton2mqtt [options] Options: -v, --verbosity possible values: "error", "warn", "info", "debug" [default: "info"] -s, --scan scan for dash buttons -m, --mapping json file containing dashbutton-mqtt mappings (see Readme) [default: "/Users/basti/WebstormProjects/dashbutton2mqtt/example.json"] -n, --name instance name. used as mqtt client id and as prefix for connection topic [default: "dashbutton"] -u, --url mqtt broker url. See https://github.com/mqttjs/MQTT.js#connect-using-a-url [default: "mqtt://127.0.0.1"] -i, --interface bind to network interface to listen for dash button presses [default: null] -p, --protocol protocol to use for button detection. possible values: "arp", "udp", "all" [default: "all"] -t, --timeout timeout between button presses. [default: 5000] -h, --help Show help [boolean] --version Show version number [boolean] 

I suggest PM2 to run dashbutton2mqtt in the background and start on system boot.

Pull requests welcome! 😀

MIT © Sebastian Raff