adding health endpoint for processor service

Author: Sachin Maheshwari

package.json

@@ -52,7 +52,8 @@
     "sequelize": "^4.21.0",
     "superagent": "^3.8.0",
     "tc-core-library-js": "appirio-tech/tc-core-library-js.git#v2.6",
-    "winston": "^2.2.0"
+    "winston": "^2.2.0",
+    "topcoder-healthcheck-dropin": "^1.0.3"
   },
   "engines": {
     "node": "6.x"

src/app.js

@@ -15,6 +15,7 @@ const logger = require('./common/logger');
 const errors = require('./common/errors');
 const models = require('./models');
 const Kafka = require('no-kafka');
+const healthcheck = require('topcoder-healthcheck-dropin')
 
 /**
  * Start Kafka consumer for event bus events.
@@ -74,11 +75,25 @@ function startKafkaConsumer(handlers, notificationServiceHandlers) {
       });
   });
 
+  const check = function () {
+    if (!consumer.client.initialBrokers && !consumer.client.initialBrokers.length) {
+      return false
+    }
+    let connected = true
+    consumer.client.initialBrokers.forEach(conn => {
+      logger.debug(`url ${conn.server()} - connected=${conn.connected}`)
+      connected = conn.connected & connected
+    })
+    return connected
+  }
 
   consumer
     .init()
-    .then(() => _.each(_.keys(handlers),
-      (topicName) => consumer.subscribe(topicName, dataHandler)))
+    .then(() => {
+      _.each(_.keys(handlers),
+        (topicName) => consumer.subscribe(topicName, dataHandler))
+      healthcheck.init([check])
+    })
     .catch((err) => {
       logger.error('Kafka Consumer failed');
       logger.error(err);