when sending protocol version and "persistent" flag, wait for the dr…

…ain events to avoid collision. Only works in node 0.6

limestone.js

@@ -121,13 +121,21 @@ exports.SphinxClient = function() {
 			     server_conn.end();
 			     callback(x);
 			 });
+
+	server_conn.on("close", function(x){
+			   if(x){
+			       console.log('closed');
+			       callback(new Error("The socket has closed due to an unknown error"));
+			   }
+		       });
+
+
 	// disable Nagle algorithm
 	server_conn.setNoDelay(true);
 
 	server_conn.addListener('connect', 
 				function () {
 				    // Sending protocol version
-				    // Here we must send 4 bytes, '0x00000001'
 				    if (server_conn.readyState == 'open') {
 					var version_number = Buffer.makeWriter();
 					version_number.push.int32(1);
@@ -136,6 +144,7 @@ exports.SphinxClient = function() {
 							     var protocol_version_raw = data.toReader();
 							     var protocol_version = protocol_version_raw.int32();
 							     // if there still data? process and callback
+							     // if sphinx has reached its max num of children, it sends retry.
 							     if(!protocol_version_raw.empty()) {
 								 status_code = protocol_version_raw.int16();
 								 version = protocol_version_raw.int16();
@@ -148,29 +157,39 @@ exports.SphinxClient = function() {
 								 }
 								 if(errmsg){
 								     callback(new Error(errmsg));
+								     return;
 								 }
 							     }
-
+							     
 							     var data_unpacked = {'': protocol_version};
 							     if (data_unpacked[""] >= 1) {
-								 //all ok, send my version
-								 server_conn.write(version_number.toBuffer());
 
 								 if(persistent){
-								     var pers_req = Buffer.makeWriter();
-								     pers_req.push.int16(Sphinx.command.PERSIST);
-								     pers_req.push.int16(0);
-								     pers_req.push.int32(4);
-								     pers_req.push.int32(1);
-								     server_conn.write(pers_req.toBuffer());
+								     server_conn.once('drain', function(){
+											  var pers_req = Buffer.makeWriter();
+											  pers_req.push.int16(Sphinx.command.PERSIST);
+											  pers_req.push.int16(0);
+											  pers_req.push.int32(4);
+											  pers_req.push.int32(1);
+											  server_conn.write(pers_req.toBuffer());
+											  server_conn.once('drain', function(){
+													       server_conn.on('data', readResponseData);
+													       _connected = true;
+													       server_conn.emit('sphinx.connected');
+													       callback(null);
+													   });
+										      });
+								 } else {
+								     server_conn.once('drain', function(){
+											  server_conn.on('data', readResponseData);
+											  _connected = true;
+											  server_conn.emit('sphinx.connected');
+											  callback(null);
+										      });
 								 }
-								 server_conn.on('data', readResponseData);
-								 _connected = true;
-								 server_conn.emit('sphinx.connected');
-
-								 // Use callback
-								 callback(null);
-
+
+								 //all ok, send my version
+								 server_conn.write(version_number.toBuffer());
 							     } else {
 								 callback(new Error('Wrong protocol version: ' + protocol_version));
 								 server_conn.end();
@@ -458,13 +477,14 @@ exports.SphinxClient = function() {
     function _enqueue(req_buf , cb, sc) {
 	if(!server_conn || !server_conn.writable){
 	    cb(new Error("Trying to enqueue. Not connected"));
+	    return;
 	}
 	_queue.push({request_buffer: req_buf, callback: cb, search_command: sc});
 	if(_queue.length === 1)
 	{
 	    if(_connected) {
 		initResponseOutput(cb);
-		server_conn.write(req_buf);
+		server_conn.write(req_buf);		    
 	    } else {
 		server_conn.once('sphinx.connected', function(){
 				     initResponseOutput(cb);