Ensure microservice monitor functions when running in discoverable mo…

…de and ZK isn't running

lib/monitors/microservice-monitor.js

@@ -7,6 +7,8 @@ var Promise  = require('bluebird').Promise;
 var async    = require('async');
 var zoologist = require('../zoologist');
 
+var CHECK_INTERVAL_MS = 2000;
+
 /**
  *  VitalSigns Health Monitor for a Microservice.
  *
@@ -28,22 +30,27 @@ var svcHealth = null;
  * Peridically check the health of the microservice.
  */
 var interval = setInterval(function() {
-  checkMicroserviceHealth()
-    .then(function (health) {
+  var check = checkMicroserviceHealth()
+
+  if (check) {
+    check.then(function (health) {
       svcHealth = health;
     });
-}, 5000);
+  }
+}, CHECK_INTERVAL_MS);
 
 /**
  * Invoke health check.
  */
-function checkMicroserviceHealth(callback) {
+function checkMicroserviceHealth() {
   var resolver = Promise.pending();
 
   if (!zoologist.getServiceDiscovery() || !zoologist.getServiceDiscovery().getData()) {
-    return resolver.resolve({
+    resolver.resolve({
       status: (zoologist.getClient().getClient().getState().name === 'SYNC_CONNECTED') ? 'UP' : 'DOWN'
     });
+
+    return resolver.promise;
   }
 
   var health = {

package.json

@@ -1,6 +1,6 @@
 {
   "name": "express-microservice-starter",
-  "version": "0.5.1",
+  "version": "0.5.2",
   "description": "An express-based Node.js API bootstrapping module for microservices.",
   "main": "index.js",
   "scripts": {