Adds notification if listeners count falls too low

Author: nakedsushi

README.md

@@ -10,6 +10,10 @@ it as a volume into your container, this script will also look to see if there
 is a stream that it can recreate from it. If it can, it will delete that existing
 stream from primary and recreate it.
 
+Screammachine can also alert by checking the streamdash api URL and finding
+the listeners count. If the listeners count fall below a certain threshold,
+it will alert (see optional env variables below).
+
 ## requirements
 
 * slack webhook url (https://api.slack.com/incoming-webhooks)
@@ -28,6 +32,12 @@ before you want this script to alert. (Example: 30)
 * `PREPEND_MESSAGE` what you'd like to prepend to the slack message. For example, if you want to `@channel` here or add
 some emoji's like `:hear_no_evil: :radio:`
 
+**optional**
+
+* `LOW_LISTENERS_THRESHOLD`
+* `STREAMDASH_HOURS_URL` the URL that your streamdash's hours api URL is at. Example: http://streamdash.com/api/hour
+
+
 This can be set up to run as a regular cronjob on a machine (`node index.js`),
 or set up as a container running as a kubernetes cronjob.
 

index.js

@@ -5,6 +5,8 @@ const SOURCE_URL = process.env.SOURCE_URL;
 const SECONDS_OFFSET = process.env.SECONDS_OFFSET;
 const WEBHOOK_URL = process.env.WEBHOOK_URL;
 const PREPEND_MESSAGE = process.env.PREPEND_MESSAGE || ':cry:';
+const LOW_LISTENERS_THRESHOLD = process.env.LOW_LISTENERS_THRESHOLD;
+const STREAMDASH_HOURS_URL = process.env.STREAMDASH_HOURS_URL;
 
 // JSON file that contains the body to POST to streammachine when creating streams.
 const streamsJson = require('./streams.json');
@@ -139,3 +141,26 @@ http.get(SOURCE_URL, (resp) => {
   notify(err.message);
 });
 
+if (LOW_LISTENERS_THRESHOLD && STREAMDASH_HOURS_URL) {
+  http.get(STREAMDASH_HOURS_URL, (resp) => {
+    let data = '';
+
+    resp.on('data', (chunk) => {
+      data += chunk;
+    });
+
+    resp.on('end', () => {
+      let notify_body = [];
+      const body = JSON.parse(data);
+      if (body === undefined) {
+        return;
+      }
+      console.log(`listeners count was ${body.listens.listeners}`);
+      if (body.listens.listeners < LOW_LISTENERS_THRESHOLD) {
+        notify(`Listeners count (${body.listens.listeners}) fell below threshold (${LOW_LISTENERS_THRESHOLD}).` +
+          `Something may be wrong with the stream. Check out Streamdash: ${STREAMDASH_HOURS_URL}`);
+      }
+    });
+  });
+}
+