maxbaines / mqtt2http

Forward MQTT messages as HTTP requests

MQTT 2 HTTP

Forward MQTT messages to HTTP.

This simple, but highly configurable script subscribes to one or more MQTT topics and makes a HTTP request for every message it receives. This allows you to use MQTT messages as trigger for APIs that don't support MQTT via services like Zapier's Webhook or IFTTT's Maker Channel.

Deploy

Deploy directly to Heroku or clone the repository and run it in any current Node.js environment:

• Yarn: yarn && yarn run start
• NPM: npm install && npm start

Test

To test you can use a public MQTT broker like mqtt://test.mosquitto.org and the DEBUG_* variables. Rename debug.env to .env for an example that publishes a JSON stringified object with the current time every 5 seconds and skips the actual request.

Environment Variables

Configure the MQTT connection and topic to subscribe to and the HTTP requests to make via environment variables. The script uses dotenv to load these from a file if you like. Be aware that some of the variables can or must be formatted as JSON strings.

The following variables can be set:

Variable	Required	Description
MQTT_URL	Yes	MQTT broker URL to connect to. See https://www.npmjs.com/package/mqtt#connect
MQTT_USERNAME	No	MQTT broker username. See https://www.npmjs.com/package/mqtt#mqttclientstreambuilder-options
MQTT_PASSWORD	No	MQTT broker password. See https://www.npmjs.com/package/mqtt#mqttclientstreambuilder-options
MQTT_CONNECT	No	MQTT broker connection options. Formatted as JSON String. See https://www.npmjs.com/package/mqtt#mqttclientstreambuilder-options
MQTT_TOPIC	Yes	MQTT topic(s) to subscribe. Either a single topic or an Array or Object formatted as JSON String. See https://www.npmjs.com/package/mqtt#subscribe
MQTT_SUBSCRIBE	No	MQTT subscribe options. Formatted as JSON String. See https://www.npmjs.com/package/mqtt#subscribe
HTTP_URL	Yes	HTTP request URL. Compiled as Handlebars template and executed with the topic and message as data. See https://www.npmjs.com/package/request#requestoptions-callback and http://handlebarsjs.com/
HTTP_JSON	No	Set to a truthy string (e.g. 1) to set the request option json to true and body to an object with the topic and message (as object, if available). See https://www.npmjs.com/package/request#requestoptions-callback
HTTP_REQUEST	No	HTTP request options. Compiled as Handlebars template and executed with the topic and message as data. Use the stringify helper if needed to output a JSON String. See https://www.npmjs.com/package/request#requestoptions-callback
DEBUG_LOG	No	Set to a truthy string (e.g. 1) to write debug logs to the console.
DEBUG_PUBLISH	No	Set to a integer string (e.g. 5000) to publish dummy topics to the broker at this interval.
DEBUG_MESSAGE	No	Message to publish. Defaults to a JSON formatted object with time set to Date.toString().
DEBUG_NOOP	No	Set to a truthy string (e.g. 1) to not actually make the HTTP request.