use eachObject to avoid async issues; support non-recurrent checks

lib/core/engine.js

@@ -32,7 +32,7 @@ Engine.prototype.init = function(_options) {
   this.servicesMonitor = new ServicesMonitor({events: this.events, logger: this.logger});
   this.servicesMonitor.addCheck('embarkVersion', function(cb) {
     return cb({name: 'Embark ' + self.version, status: 'green'});
-  });
+  }, 0);
 };
 
 Engine.prototype.startMonitor = function() {
@@ -160,7 +160,6 @@ Engine.prototype.webServerService = function(options) {
 Engine.prototype.ipfsService = function(options) {
   var self = this;
   self.servicesMonitor.addCheck('IPFS', function(cb) {
-
     utils.checkIsAvailable('http://localhost:5001', function(available) {
       if (available) {
         //Ideally this method should be in an IPFS API JSONRPC wrapper

lib/core/services_monitor.js

@@ -3,6 +3,18 @@ var async = require('async');
 var http = require('http');
 var utils = require('./utils.js');
 
+// TODO: repeated, add this to an async extensions file
+function asyncEachObject(object, iterator, callback) {
+  async.each(
+    Object.keys(object || {}),
+    function(key, next){
+      iterator(key, object[key], next);
+    },
+    callback
+  );
+}
+async.eachObject = asyncEachObject;
+
 var ServicesMonitor = function(options) {
   this.events = options.events;
   this.logger = options.logger;
@@ -12,34 +24,38 @@ var ServicesMonitor = function(options) {
 };
 
 ServicesMonitor.prototype.addCheck = function(name, checkFn, time) {
-  this.logger.info('add check');
+  this.logger.info('add check: ' + name);
   // TODO: check if a service with the same name already exists
   this.checkList[name] = {fn: checkFn, interval: time || 5000};
 };
 
 ServicesMonitor.prototype.startMonitor = function() {
+  this.logger.info('startMonitor');
   var self = this;
-  var checkName;
-
-  for (checkName in this.checkList) {
-    var check = this.checkList[checkName];
 
+  async.eachObject(this.checkList, function(checkName, check, callback) {
     self.events.on('check:' + checkName, function(obj) {
-      self.logger.info(JSON.stringify(obj));
+      //self.logger.info('checked ' + checkName);
+      //self.logger.info(JSON.stringify(obj));
+      //self.logger.info(JSON.stringify(self.checkState));
       self.checkState[checkName] = obj.name[obj.status];
       self.events.emit("servicesState", self.checkState);
     });
 
-    this.checkTimers[checkName] = setInterval(function() {
+    if (check.interval !== 0) {
+      self.checkTimers[checkName] = setInterval(function() {
         check.fn.call(check.fn, function(obj) {
           self.events.emit('check:' + checkName, obj);
         });
       }, check.interval);
+    }
 
     check.fn.call(check.fn, function(obj) {
       self.events.emit('check:' + checkName, obj);
     });
-  }
+  }, function(err) {
+  });
+  this.logger.info(JSON.stringify(this.checkState));
 };
 
 // TODO: old checks to be moved