Add redis configuration to streaming API

streaming/index.js

@@ -78,7 +78,11 @@ const streamFrom = (id, req, res, needsFiltering = false) => {
   res.setHeader('Content-Type', 'text/event-stream')
   res.setHeader('Transfer-Encoding', 'chunked')
 
-  const redisClient = redis.createClient()
+  const redisClient = redis.createClient({
+    host:     process.env.REDIS_HOST     || '127.0.0.1',
+    port:     process.env.REDIS_PORT     || 6379,
+    password: process.env.REDIS_PASSWORD
+  })
 
   redisClient.on('message', (channel, message) => {
     const { event, payload } = JSON.parse(message)