On unexpected connection close disallow enqueue (#79)

Author: alexpenev-s

lib/protocol/Connection.js

@@ -363,6 +363,12 @@ Connection.prototype.receive = function receive(buffer, cb) {
 
 Connection.prototype.enqueue = function enqueue(task, cb) {
   var queueable;
+
+  if (!this._socket) {
+    var err = new Error('Connection closed');
+    err.code = 'EHDBCLOSE';
+    return cb(err)
+  }
   if (util.isFunction(task)) {
     queueable = this._queue.createTask(task, cb);
     queueable.name = task.name;
@@ -600,4 +606,4 @@ InitializationReply.read = function readInitializationReply(buffer) {
 
 var initializationRequestBuffer = new Buffer([
   0xff, 0xff, 0xff, 0xff, 4, 20, 0, 4, 1, 0, 0, 1, 1, 1
-]);
+]);

test/lib.Connection.js

@@ -324,6 +324,9 @@ describe('Lib', function () {
 
     it('should enqueue a mesage', function () {
       var connection = createConnection();
+      connection._socket = {
+        readyState: 'open'
+      };
       connection._queue.pause();
       connection.enqueue(function firstTask() {});
       connection.enqueue(new lib.request.Segment(MessageType.EXECUTE));
@@ -338,6 +341,15 @@ describe('Lib', function () {
       taskNames.should.eql(['firstTask', 'EXECUTE', 'thirdTask']);
     });
 
+    it('should report error in enqueue when connection is invalid', function (done) {
+      var connection = createConnection();
+      connection._queue.pause();
+      connection.enqueue(function firstTask() { }, function (err) {
+        err.code.should.equal('EHDBCLOSE');
+        done();
+      });
+    });
+
     it('should rollback a transaction', function () {
       var connection = createConnection();
       connection.enqueue = function enqueue(msg, done) {