feat(cluster): add Cluster#quit() to quit cluster gracefully. (#339)

Close #315

Author: luin

API.md

@@ -153,14 +153,14 @@ the current connection.
 var redis = new Redis();
 redis.monitor(function (err, monitor) {
   // Entering monitoring mode.
-  monitor.on('monitor', function (time, args) {
+  monitor.on('monitor', function (time, args, source, database) {
     console.log(time + ": " + util.inspect(args));
   });
 });
 
 // supports promise as well as other commands
 redis.monitor().then(function (monitor) {
-  monitor.on('monitor', function (time, args) {
+  monitor.on('monitor', function (time, args, source, database) {
     console.log(time + ": " + util.inspect(args));
   });
 });
@@ -218,6 +218,7 @@ Create a Redis instance
     * [new Cluster(startupNodes, options)](#new_Cluster_new)
     * [.connect()](#Cluster+connect) ⇒ <code>Promise</code>
     * [.disconnect()](#Cluster+disconnect)
+    * [.quit(callback)](#Cluster+quit) ⇒ <code>Promise</code>
     * [.nodes([role])](#Cluster+nodes) ⇒ <code>[Array.&lt;Redis&gt;](#Redis)</code>
     * [.getBuiltinCommands()](#Commander+getBuiltinCommands) ⇒ <code>Array.&lt;string&gt;</code>
     * [.createBuiltinCommand(commandName)](#Commander+createBuiltinCommand) ⇒ <code>object</code>
@@ -258,6 +259,19 @@ Disconnect from every node in the cluster.
 
 **Kind**: instance method of <code>[Cluster](#Cluster)</code>  
 **Access:** public  
+<a name="Cluster+quit"></a>
+
+### cluster.quit(callback) ⇒ <code>Promise</code>
+Quit the cluster gracefully.
+
+**Kind**: instance method of <code>[Cluster](#Cluster)</code>  
+**Returns**: <code>Promise</code> - return 'OK' if successfully  
+**Access:** public  
+
+| Param | Type |
+| --- | --- |
+| callback | <code>function</code> | 
+
 <a name="Cluster+nodes"></a>
 
 ### cluster.nodes([role]) ⇒ <code>[Array.&lt;Redis&gt;](#Redis)</code>

lib/cluster/index.js

@@ -208,6 +208,29 @@ Cluster.prototype.disconnect = function (reconnect) {
   this.connectionPool.reset([]);
 };
 
+/**
+ * Quit the cluster gracefully.
+ *
+ * @param {function} callback
+ * @return {Promise} return 'OK' if successfully
+ * @public
+ */
+Cluster.prototype.quit = function (callback) {
+  this.setStatus('disconnecting');
+
+  this.manuallyClosing = true;
+
+  if (this.reconnectTimeout) {
+    clearTimeout(this.reconnectTimeout);
+    this.reconnectTimeout = null;
+  }
+  return Promise.all(this.nodes().map(function (node) {
+    return node.quit();
+  })).then(function () {
+    return 'OK';
+  }).nodeify(callback);
+};
+
 /**
  * Get nodes with the specified role
  *

test/functional/cluster.js

@@ -1284,6 +1284,40 @@ describe('cluster', function () {
       });
     });
   });
+
+  describe('#quit()', function () {
+    it('should quit the connection gracefully', function (done) {
+      var slotTable = [
+        [0, 1, ['127.0.0.1', 30001]],
+        [2, 16383, ['127.0.0.1', 30002], ['127.0.0.1', 30003]]
+      ];
+      var argvHandler = function (argv) {
+        if (argv[0] === 'cluster' && argv[1] === 'slots') {
+          return slotTable;
+        }
+      };
+      var node1 = new MockServer(30001, argvHandler);
+      var node2 = new MockServer(30002, argvHandler);
+      var node3 = new MockServer(30003, argvHandler);
+
+      var cluster = new Redis.Cluster([
+        { host: '127.0.0.1', port: '30001' }
+      ]);
+
+      var setCommandHandled = false;
+      cluster.on('ready', function () {
+        cluster.set('foo', 'bar', function () {
+          setCommandHandled = true;
+        });
+        cluster.quit(function (err, state) {
+          expect(setCommandHandled).to.eql(true);
+          expect(state).to.eql('OK');
+          cluster.disconnect();
+          disconnect([node1, node2, node3], done);
+        });
+      });
+    });
+  });
 });
 
 function disconnect(clients, callback) {