Fix cluster listening support #211 (#334)

* Adding most listen cluster support

* Moving distributed-state-registry to cluster package

* Adding unit tests for cluster functionality

* Adding more cluster based listen tests

* Removing test listener leak

* comments and minor tweaks

* Code review

* Changing default timeout values

* Reverting package updates

* Code review suggestions

conf/config.yml

@@ -113,4 +113,10 @@ clusterKeepAliveInterval: 5000
 # The interval at which all nodes within a cluster registry are checked for timeouts
 clusterActiveCheckInterval: 1000
 # The longest duration since the last status message was received until the remote node is declared inactive
-clusterNodeInactiveTimeout: 6000
+clusterNodeInactiveTimeout: 6000
+# The amount of time to wait for a provider to acknowledge or reject a listen request
+listenResponseTimeout: 500
+# The amount of time a lock can be reserved for before it is force released
+lockTimeout: 1000
+# The amount of time a lock request waits for before it defaults to false
+lockRequestTimeout: 1000

package.json

@@ -10,7 +10,7 @@
     "test": "test"
   },
   "scripts": {
-    "coverage": "istanbul cover node_modules/jasmine/bin/jasmine.js JASMINE_CONFIG_PATH=jasmine.json",
+    "coverage": "istanbul cover node_modules/jasmine/bin/jasmine.js JASMINE_CONFIG_PATH=jasmine.json -x **/pid-helper.js",
     "watch": "node node_modules/watch/cli.js \"npm test\" ./src ./test",
     "reporter": "node jasmine-runner",
     "test": "jasmine JASMINE_CONFIG_PATH=jasmine.json",
@@ -26,27 +26,26 @@
   },
   "dependencies": {
     "adm-zip": "^0.4.7",
-    "colors": "1.0.3",
+    "colors": "^1.0.3",
     "commander": "^2.9.0",
     "engine.io": "1.6.11",
     "glob": "^7.0.5",
     "js-yaml": "^3.6.1",
     "mkdirp": "^0.5.1",
-    "needle": "^1.0.0"
+    "needle": "^1.1.0"
   },
   "devDependencies": {
     "async": "^0.2.9",
-    "coveralls": "^2.11.9",
+    "coveralls": "^2.11.12",
     "engine.io-client": "^1.6.11",
-    "grunt": "^1.0.1 ",
-    "grunt-release": "^0.14.0",
-    "istanbul": "^0.4.3",
+    "grunt": "^1.0.1",
+    "istanbul": "^0.4.4",
     "jasmine": "^2.4.1",
     "jasmine-spec-reporter": "^2.5.0",
     "n0p3": "^1.0.2",
     "nexe": "^1.1.2",
     "proxyquire": "1.7.10",
-    "watch": "^0.19.1"
+    "watch": "^0.19.2"
   },
   "author": "deepstreamHub GmbH",
   "license": "AGPL-3.0",

src/cluster/cluster-registry.js

@@ -13,7 +13,7 @@ const EventEmitter = require( 'events' ).EventEmitter;
  * @emits add <serverName>
  * @emits remove <serverName>
  */
-module.exports = class ClusterRegistry extends EventEmitter{
+module.exports = class ClusterRegistry extends EventEmitter {
 
 	/**
 	 * Creates the class, initialises all intervals and publishes the
@@ -61,7 +61,11 @@ module.exports = class ClusterRegistry extends EventEmitter{
 			action: C.ACTIONS.REMOVE,
 			data:[ this._options.serverName ]
 		});
-		this._options.messageConnector.unsubscribe( C.TOPIC.CLUSTER, this._onMessageFn );
+
+		// TODO: If a message connector doesn't close this is required to avoid an error
+		// being thrown during shutdown
+		//this._options.messageConnector.unsubscribe( C.TOPIC.CLUSTER, this._onMessageFn );
+
 		process.removeListener( 'beforeExit', this._leaveClusterFn );
 		process.removeListener( 'exit', this._leaveClusterFn );
 		clearInterval( this._publishInterval );
@@ -80,6 +84,18 @@ module.exports = class ClusterRegistry extends EventEmitter{
 		return Object.keys( this._nodes );
 	}
 
+	/**
+	 * Returns true if this node is the cluster leader
+	 * @return {Boolean} [description]
+	 */
+	isLeader() {
+		return this._options.serverName === this.getCurrentLeader();
+	}
+
+	/**
+	* Returns the name of the current leader
+	* @return {String}
+	*/
 	getCurrentLeader() {
 		var maxScore = 0,
 			serverName,