particle-sse-proxy

A NodeJS reverse-proxy for Server Sent Event Sources -> Particle.io Events

Introduction

The Particle.io cloud supports webhooks, but these webhooks can't process an event stream. This reverse-proxy allows a webhook to use a REST call to subscribe to an event stream and translate EventSource messages to Particle.io cloud events.

Usage

Send a REST PUT to the proxy with the following json data:

{ 
	"device_id" : "0123456789", 
	"particle_token" : "0123456789abcdef", 
	"event_source" : "http://my.event.source", 
	"events" : [ "event1", "event2" ],
	"headers" : { "Authorization" : "Bearer myToken",
	"isPrivate" : true
}

The server will verify your device_id and particle_token with the Particle.io cloud, then establish an event stream, using any headers that you pass it. (The headers field is optional.) Any incoming SSE events will be published as Particle.io events with a name matching the event type, using the Particle.io token you provided.

Additionally, messages with no type will be published as onmessage events. onopen and onerror events will also be published. Send a REST DELETE to the proxy to end the event stream.

WebHook Example

webhook.json.example has been provided to demonstrate how to use a WebHook to make a Particle.io subscription. After adding the WebHook, you can use the following firmware code to subscribe and consume events:

Particle.subscribe("event1", event1Handler);
Particle.subscribe("event2", event2Handler);
Particle.publish("sse");

Deploying to Heroku

I tested this reverse proxy on Heroku. To setup Heroku, make sure you have command line git, the Heroku Toolbelt, and a verified account. To deploy this reverse proxy, do the following:

• Clone this repo

   git clone https://github.com/jychuah/particle-sse-proxy
   cd particle-sse-proxy
  

• Create a Heroku dyno and make a note of the endpoint. (Heroku services always run on port 80, so your PORT variable will be ignored.)

   heroku login
   heroku create
  

• Push it to Heroku

   git push heroku master
  

• Check to see if it's running with

   heroku logs --tail