diff --git a/SSDB.js b/SSDB.js
index bba75b7..7b99bbb 100644
--- a/SSDB.js
+++ b/SSDB.js
@@ -10,22 +10,23 @@
 var net = require('net');
 
 // timeout: microseconds, if ommitted, it will be treated as listener
+// option = unix path or {host, port, timeout}
 // callback(err, ssdb)
-exports.connect = function(host, port, timeout, listener){
+exports.connect = function(opts, listener){
 	var self = this;
-	var recv_buf = new Buffer(0);
+	var recv_buf = Buffer.alloc(0);
 	var callbacks = [];
 	var connected = false;
-
-	if(typeof(timeout) == 'function'){
-		listener = timeout;
-		timeout = 0;
+	
+	//timeout = timeout || 0;
+	//listener = listener || function(){};
+	
+	if (!opts){
+		opts = {port:8888, host:'localhost'};
 	}
-	timeout = timeout || 0;
-	listener = listener || function(){};
 
 	var sock = new net.Socket();
-	sock.on('error', function(e){
+	sock.on('error', function(e){		
 		if(!connected){
 			listener('connect_failed', e);
 		}else{
@@ -33,11 +34,26 @@ exports.connect = function(host, port, timeout, listener){
 			callback(['error']);
 		}
 	});
-	sock.connect(port, host, function(){
+	
+	sock.on('data', function(data){
+		recv_buf = build_buffer([recv_buf, data]);
+		while(recv_buf.length > 0){
+			var resp = parse();
+			if(!resp){
+				break;
+			}
+			resp[0] = resp[0].toString();
+			var callback = callbacks.shift();
+			callback(resp);
+		}
+	});
+
+	sock.connect(opts, function(){
+		//console.log('Socket connected!');		
 		connected = true;
 		sock.setNoDelay(true);
 		sock.setKeepAlive(true);
-		sock.setTimeout(timeout);
+		sock.setTimeout(0); //timeout);
 		listener(0, self);
 	});
 
@@ -59,12 +75,12 @@ exports.connect = function(host, port, timeout, listener){
 			if(arg instanceof Buffer){
 				//
 			}else{
-				arg = new Buffer(arg.toString());
+				arg = Buffer.from(arg.toString());
 			}
 			bs.push(arg);
 			size += arg.length;
 		}
-		var ret = new Buffer(size);
+		var ret = Buffer.alloc(size);
 		var offset = 0;
 		for(var i=0; i<bs.length; i++){
 			bs[i].copy(ret, offset);
@@ -89,25 +105,12 @@ exports.connect = function(host, port, timeout, listener){
 			bs.push('\n');
 		}
 		bs.push('\n');
-		var req = build_buffer(bs);
-		sock.write(req);
+		
+		sock.write( build_buffer(bs) );
 		//console.log('write ' + req.length + ' bytes');
 		//console.log('write: ' + req);
 	}
 
-	sock.on('data', function(data){
-		recv_buf = build_buffer([recv_buf, data]);
-		while(recv_buf.length > 0){
-			var resp = parse();
-			if(!resp){
-				break;
-			}
-			resp[0] = resp[0].toString();
-			var callback = callbacks.shift();
-			callback(resp);
-		}
-	});
-
 	function memchr(buf, ch, start){
 		start = start || 0;
 		ch = typeof(ch) == 'string'? ch.charCodeAt(0) : ch;
@@ -180,28 +183,45 @@ exports.connect = function(host, port, timeout, listener){
 
 	// callback(err, val);
 	// err: 0 on sucess, or error_code(string) on error
+	
+	
+	self.compact = function(callback){
+		self.request('compact', function(resp){
+			if(callback){
+				let err = resp[0] == 'ok'? 0 : resp[0];
+				callback(err, resp[1].toString());
+			}
+		});
+	}
+	
+	
+	////////////////// Key Value
+	
+	//get key Get the value related to the specified key
 	self.get = function(key, callback){
 		self.request('get', [key], function(resp){
 			if(callback){
-				var err = resp[0] == 'ok'? 0 : resp[0];
-				var val = resp[1];
-				callback(err, val);
+				let err = resp[0] == 'ok'? 0 : resp[0];
+				callback(err, resp[1].toString());
 			}
 		});
 	}
 
-	// callback(err);
+	//set key value Set the value of the key.
 	self.set = function(key, val, callback){
 		self.request('set', [key, val], function(resp){
 			if(callback){
-				var err = resp[0] == 'ok'? 0 : resp[0];
+				let err = resp[0] == 'ok'? 0 : resp[0];
 				callback(err);
 			}
 		});
 	}
 
-	// callback(err);
+	//setx key value ttl Set the value of the key, with a time to live. 
     self.setx = function(key, val, ttl, callback){
+		if (!ttl) ttl = 0;
+			ttl = parseInt(ttl);		
+		
         self.request('setx', [key, val, ttl], function(resp){
             if(callback){
                 var err = resp[0] == 'ok'? 0 : resp[0];
@@ -209,18 +229,51 @@ exports.connect = function(host, port, timeout, listener){
             }
         });
     }
-
-    // callback(err);
+	
+	//setnx key value Set the string value in argument as value of the key only if the key doesn"t exist.
+	self.setnx = function(key, val, callback){
+        self.request('setnx', [key, val], function(resp){
+            if(callback){
+                var err = resp[0] == 'ok'? 0 : resp[0];
+                callback(err, parseInt(resp[1].toString()));
+            }
+        });
+    }
+	
+	//expire key ttl Set the time left to live in seconds, only for keys of KV type.
+	self.expire = function(key, ttl, callback){
+		if (!ttl) ttl = 0;
+			ttl = parseInt(ttl);		
+		
+        self.request('expire', [key, ttl], function(resp){
+            if(callback){
+                var err = resp[0] == 'ok'? 0 : resp[0];
+                callback(err, parseInt(resp[1].toString()));
+            }
+        });
+    }
+	
+	//ttl key Returns the time left to live in seconds, only for keys of KV type.
     self.ttl = function(key, callback){
         self.request('ttl', [key], function(resp){
             if(callback){
                 var err = resp[0] == 'ok'? 0 : resp[0];
-                callback(err,resp[1].toString());
+                callback(err, resp[1].toString());
             }
         });
     }
-
-	// callback(err);
+	
+	//getset key value Sets a value and returns the previous entry at that key.
+	self.getset = function(key, val, callback){
+        self.request('getset', [key, val], function(resp){
+            if(callback){
+                var err = resp[0] == 'ok'? 0 : resp[0];
+                callback(err, resp[1].toString());
+            }
+        });
+    }
+	
+	//del key Delete specified key.
 	self.del = function(key, callback){
 		self.request('del', [key], function(resp){
 			if(callback){
@@ -229,21 +282,158 @@ exports.connect = function(host, port, timeout, listener){
 			}
 		});
 	}
+	
+	//incr key [num] Increment the number stored at key by num.
+	self.incr = function(key, num, callback){
+        if (!num) num = 1;
+		num = parseInt( num );		
+		
+		self.request('incr', [key, num], function(resp){
+            if(callback){
+                var err = resp[0] == 'ok'? 0 : resp[0];
+                callback(err, parseInt( resp[1].toString() ));
+            }
+        });
+    }
+	
+	//exists key Verify if the specified key exists.
+	self.exists = function(key, callback){
+		self.request('exists', [key], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				callback(err, parseInt( resp[1].toString() ));
+			}
+		});
+	}
+	
+	//bit operations @todo 
+	
+	
+	//substr key start size Return part of a string.
+	self.substr = function(key, start, size, callback){
+        if (!start) start = 0;
+		if (!size) size = 1;	
+		
+		self.request('substr', [key, start, size], function(resp){
+            if(callback){
+                var err = resp[0] == 'ok'? 0 : resp[0];
+                callback(err, resp[1].toString());
+            }
+        });
+    }
+	
+	//strlen key Return the number of bytes of a string.
+	self.strlen = function(key, callback){
+		self.request('strlen', [key], function(resp){
+            if(callback){
+                var err = resp[0] == 'ok'? 0 : resp[0];
+                callback(err, parseInt( resp[1].toString() ));
+            }
+        });
+    }
+	
+	//rkeys key_start key_end limit List keys in range (key_start, key_end], in reverse order.
+	self.rkeys = function(key_start, key_end, limit, callback){
+		if (typeof(limit) == 'function'){
+			callback = limit;
+			limit = 9223372036854775807;
+		}
+		
+		self.request('rkeys', [key_start, key_end, limit], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				var data = [];
+				for(var i=1; i<resp.length; i++){
+					data.push( resp[i].toString() );
+				}
+				callback(err, data);
+			}
+		});
+	}
+	
+	//rscan key_start key_end limit List key-value pairs with keys in range (key_start, key_end], in reverse order.
+	self.rscan = function(key_start, key_end, limit, callback){
+		if (typeof(limit) == 'function'){
+			callback = limit;
+			limit = 9223372036854775807;
+		}
+		
+		self.request('rscan', [key_start, key_end, limit], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				if(resp.length % 2 != 1){
+					callback('error');
+				}else{
+					var data = {};
+					for(var i=1; i<resp.length; i+=2){
+						data[ resp[i].toString() ] = resp[i+1].toString();
+					}
+					callback(err, data);
+				}
+			}
+		});
+	}
 
-	// callback(err, {index:[], items:{key:score}})
+	//multi_set key1 value1 key2 value2 ... Set multiple key-value pairs(kvs) in one method call.
+	self.multi_set = function(kv, callback){
+		let nkv = [];
+		if (kv){		
+			Object.keys(kv).forEach(function(k){
+				if (kv[k]){
+					nkv.push( k );
+					nkv.push( kv[k] );
+				}
+			});
+		}
+				
+		self.request('multi_set', nkv, function(resp){
+			if(callback){
+				let err = resp[0] == 'ok'? 0 : resp[0];
+				callback(err, resp[1].toString());
+			}
+		});
+	}
+
+	//multi_get key1 key2 ... Get the values related to the specified multiple keys
+	self.multi_get = function(k, callback){
+		self.request('multi_get', k, function(resp){
+			if(callback){
+				let err = resp[0] == 'ok'? 0 : resp[0];
+				var data = {};
+				for(var i=1; i<resp.length; i+=2){
+					data[ resp[i].toString() ] = resp[i+1].toString();
+				}
+				callback(err, data);
+			}
+		});
+	}
+
+	//multi_del key1 key2 ... Delete specified multiple keys.
+	self.multi_del = function(k, callback){
+		self.request('multi_del', k, function(resp){
+			if(callback){
+				let err = resp[0] == 'ok'? 0 : resp[0];
+				callback(err, resp[1].toString());
+			}
+		});
+	}
+
+	//scan key_start key_end limit List key-value pairs with keys in range (key_start, key_end].
 	self.scan = function(key_start, key_end, limit, callback){
+		if (typeof(limit) == 'function'){
+			callback = limit;
+			limit = 9223372036854775807;
+		}
+		
 		self.request('scan', [key_start, key_end, limit], function(resp){
 			if(callback){
 				var err = resp[0] == 'ok'? 0 : resp[0];
 				if(resp.length % 2 != 1){
 					callback('error');
 				}else{
-					var data = {index: [], items: {}};
+					var data = {};
 					for(var i=1; i<resp.length; i+=2){
-						var k = resp[i].toString();
-						var v = resp[i+1].toString();
-						data.index.push(k);
-						data.items[k] = v;
+						data[ resp[i].toString() ] = resp[i+1].toString();
 					}
 					callback(err, data);
 				}
@@ -251,31 +441,29 @@ exports.connect = function(host, port, timeout, listener){
 		});
 	}
 
-	// callback(err, [])
+	//keys key_start key_end limit List keys in range (key_start, key_end].
 	self.keys = function(key_start, key_end, limit, callback){
 		self.request('keys', [key_start, key_end, limit], function(resp){
 			if(callback){
 				var err = resp[0] == 'ok'? 0 : resp[0];
 				var data = [];
 				for(var i=1; i<resp.length; i++){
-					var k = resp[i].toString();
-					data.push(k);
+					data.push( resp[i].toString() );
 				}
 				callback(err, data);
 			}
 		});
 	}
 
-	//////////////////////////////////////////////
+	////////////////// Sorted set
 
-	// callback(score)
+	//zget name key Get the score related to the specified key of a zset
 	self.zget = function(name, key, callback){
 		self.request('zget', [name, key], function(resp){
 			if(callback){
 				var err = resp[0] == 'ok'? 0 : resp[0];
 				if(resp.length == 2){
-					var score = parseInt(resp[1]);
-					callback(err, score);
+					callback(err, parseInt(resp[1]));
 				}else{
 					var score = 0;
 					callback('error');
@@ -284,14 +472,13 @@ exports.connect = function(host, port, timeout, listener){
 		});
 	}
 
-	// callback(size)
+	//zsize name Return the number of pairs of a zset.
 	self.zsize = function(name, callback){
 		self.request('zsize', [name], function(resp){
 			if(callback){
 				var err = resp[0] == 'ok'? 0 : resp[0];
 				if(resp.length == 2){
-					var size = parseInt(resp[1]);
-					callback(err, size);
+					callback(err, parseInt(resp[1]));
 				}else{
 					var score = 0;
 					callback('error');
@@ -300,7 +487,7 @@ exports.connect = function(host, port, timeout, listener){
 		});
 	}
 
-	// callback(err);
+	//zset name key score Set the score of the key of a zset.
 	self.zset = function(name, key, score, callback){
 		self.request('zset', [name, key, score], function(resp){
 			if(callback){
@@ -310,7 +497,7 @@ exports.connect = function(host, port, timeout, listener){
 		});
 	}
 
-	// callback(err);
+	//zdel name key Delete specified key of a zset.
 	self.zdel = function(name, key, callback){
 		self.request('zdel', [name, key], function(resp){
 			if(callback){
@@ -320,7 +507,7 @@ exports.connect = function(host, port, timeout, listener){
 		});
 	}
 
-	// callback(err, {index:[], items:{key:score}})
+	//zscan name key_start score_start score_end limit List key-score pairs where key-score in range (key_start+score_start, score_end].
 	self.zscan = function(name, key_start, score_start, score_end, limit, callback){
 		self.request('zscan', [name, key_start, score_start, score_end, limit], function(resp){
 			if(callback){
@@ -328,12 +515,9 @@ exports.connect = function(host, port, timeout, listener){
 				if(resp.length % 2 != 1){
 					callback('error');
 				}else{
-					var data = {index: [], items: {}};
+					var data = {};
 					for(var i=1; i<resp.length; i+=2){
-						var k = resp[i].toString();
-						var v = parseInt(resp[i+1]);
-						data.index.push(k);
-						data.items[k] = v;
+						data[ resp[i].toString() ] = parseInt(resp[i+1]);
 					}
 					callback(err, data);
 				}
@@ -341,123 +525,878 @@ exports.connect = function(host, port, timeout, listener){
 		});
 	}
 
-	// callback(err, [])
+	//zlist name_start name_end limit List zset names in range (name_start, name_end].
 	self.zlist = function(name_start, name_end, limit, callback){
+		if (typeof(limit) == 'function'){
+			callback = limit;
+			limit = 9223372036854775807;
+		}
+				
 		self.request('zlist', [name_start, name_end, limit], function(resp){
 			if(callback){
 				var err = resp[0] == 'ok'? 0 : resp[0];
 				var data = [];
 				for(var i=1; i<resp.length; i++){
-					var k = resp[i].toString();
-					data.push(k);
+					data.push( resp[i].toString() );
 				}
 				callback(err, data);
 			}
 		});
 	}
 	
-	// callback(err,sum)
+	//zsum name score_start score_end Returns the sum of elements of the sorted set stored at the specified key which have scores in the range [score_start,score_end].
 	self.zsum = function(name, score_start, score_end, callback){
-		self.request('zsum', [name,score_start,score_end], function(resp){
+		self.request('zsum', [name, score_start, score_end], function(resp){
 			if(callback){
 				var err = resp[0] == 'ok'? 0 : resp[0];
 				if(resp.length == 2){
-					var size = parseInt(resp[1]);
-					callback(err, size);
+					callback(err, parseInt(resp[1]));
 				}else{
 					callback('error');
 				}
 			}
 		});
 	}
-
-	//////////////////////////////////////////////
-
-	// callback(val)
-	self.hget = function(name, key, callback){
-		self.request('hget', [name, key], function(resp){
+	
+	//zavg name score_start score_end Returns the average of elements of the sorted set stored at the specified key which have scores in the range [score_start,score_end].
+	self.zavg = function(name, score_start, score_end, callback){
+		self.request('zavg', [name, score_start, score_end], function(resp){
 			if(callback){
 				var err = resp[0] == 'ok'? 0 : resp[0];
 				if(resp.length == 2){
-					callback(err, resp[1]);
+					callback(err, parseInt(resp[1]));
 				}else{
 					callback('error');
 				}
 			}
 		});
 	}
-
-	// callback(err);
-	self.hset = function(name, key, val, callback){
-		self.request('hset', [name, key, val], function(resp){
+	
+	//zclear name Delete all keys in a zset.
+	self.zclear = function(name, callback){
+		self.request('zclear', [name], function(resp){
 			if(callback){
 				var err = resp[0] == 'ok'? 0 : resp[0];
 				callback(err);
 			}
 		});
 	}
-
-	// callback(err);
-	self.hdel = function(name, key, callback){
-		self.request('hdel', [name, key], function(resp){
+	
+	//zexists name key Verify if the specified key exists in a zset.
+	self.zexists = function(name, key, callback){
+		self.request('zexists', [name, key], function(resp){
 			if(callback){
 				var err = resp[0] == 'ok'? 0 : resp[0];
-				callback(err);
+				callback(err, parseInt(resp[1]));				
 			}
 		});
 	}
-
-	// callback(err, {index:[], items:{key:score}})
-	self.hscan = function(name, key_start, key_end, limit, callback){
-		self.request('hscan', [name, key_start, key_end, limit], function(resp){
+	
+	//zincr name key num Increment the number stored at key in a zset by num.
+	self.zincr = function(name, key, num, callback){
+		num = parseInt(num);		
+		self.request('zincr', [name, key, num], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				callback(err);				
+			}
+		});
+	}
+	
+	//zrlist name_start name_end limit List zset names in range (name_start, name_end], in reverse order.
+	self.zrlist = function(name_start, name_end, limit, callback){
+		if (typeof(limit) == 'function'){
+			callback = limit;
+			limit = 9223372036854775807;
+		}
+		
+		self.request('zrlist', [name_start, name_end, limit], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				var data = [];
+				for(var i=1; i<resp.length; i++){
+					data.push( resp[i].toString() );
+				}
+				callback(err, data);
+			}
+		});
+	}
+	
+	//zkeys name key_start score_start score_end limit List keys in a zset.
+	self.zkeys = function(name, key_start, score_start, score_end, limit, callback){
+		if (typeof(limit) == 'function'){
+			callback = limit;
+			limit = 9223372036854775807;
+		}
+		
+		self.request('zkeys', [name, key_start, score_start, score_end, limit], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				var data = [];
+				for(var i=1; i<resp.length; i++){
+					data.push( resp[i].toString() );
+				}
+				callback(err, data);
+			}
+		});
+	}
+	
+	//zrscan name key_start score_start score_end limit List key-score pairs of a zset, in reverse order. See method zkeys().
+	self.zrscan = function(name, key_start, score_start, score_end, limit, callback){
+		if (typeof(limit) == 'function'){
+			callback = limit;
+			limit = 9223372036854775807;
+		}
+		
+		self.request('zrscan', [name, key_start, score_start, score_end, limit], function(resp){
 			if(callback){
 				var err = resp[0] == 'ok'? 0 : resp[0];
 				if(resp.length % 2 != 1){
 					callback('error');
 				}else{
-					var data = {index: [], items: {}};
+					var data = {};
 					for(var i=1; i<resp.length; i+=2){
-						var k = resp[i].toString();
-						var v = resp[i+1].toString();
-						data.index.push(k);
-						data.items[k] = v;
+						data[ resp[i].toString() ] = parseInt(resp[i+1]);
 					}
 					callback(err, data);
 				}
 			}
 		});
 	}
-
-	// callback(err, [])
-	self.hlist = function(name_start, name_end, limit, callback){
-		self.request('hlist', [name_start, name_end, limit], function(resp){
+	
+	//zrank name key Returns the rank(index) of a given key in the specified sorted set.
+	self.zrank = function(name, key, callback){
+		self.request('zrank', [name, key], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				callback(err, parseInt(resp[1]));				
+			}
+		});
+	}
+	
+	//zrrank name key Returns the rank(index) of a given key in the specified sorted set, in reverse order.
+	//@todo fix returned results
+	self.zrrank = function(name, key, callback){
+		self.request('zrank', [name, key], function(resp){
 			if(callback){
 				var err = resp[0] == 'ok'? 0 : resp[0];
 				var data = [];
 				for(var i=1; i<resp.length; i++){
-					var k = resp[i].toString();
-					data.push(k);
+					data.push( resp[i].toString() );
 				}
-				callback(err, data);
+				callback(err, data);				
 			}
 		});
 	}
-
-	// callback(size)
-	self.hsize = function(name, callback){
-		self.request('hsize', [name], function(resp){
+	
+	//zcount name score_start score_end Returns the number of elements of the sorted set stored at the specified key which have scores in the range [score_start,score_end].
+	self.zcount = function(name, score_start, score_end, callback){
+		self.request('zcount', [name, score_start, score_end], function(resp){
 			if(callback){
 				var err = resp[0] == 'ok'? 0 : resp[0];
-				if(resp.length == 2){
-					var size = parseInt(resp[1]);
-					callback(err, size);
-				}else{
-					var score = 0;
-					callback('error');
-				}
+				callback(err, parseInt(resp[1]));				
+			}
+		});
+	}
+	
+	//zpop_front name limit Delete limit elements from front of the zset.
+	self.zpop_front = function(name, limit, callback){
+		self.request('zpop_front', [name, parseInt(limit)], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				callback(err, parseInt(resp[1]));				
 			}
 		});
 	}
+	
+	//zpop_back name limit Delete limit elements from back of the zset.
+	self.zpop_back = function(name, limit, callback){
+		self.request('zpop_back', [name, parseInt(limit)], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				callback(err, parseInt(resp[1]));				
+			}
+		});
+	}
+	
+	//zremrangebyrank name start end Delete the elements of the zset which have rank in the range [start,end].
+	self.zremrangebyrank = function(name, start, end, callback){
+		self.request('zremrangebyrank', [name, parseInt(start), parseInt(end)], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				callback(err, parseInt(resp[1]));				
+			}
+		});
+	}
+	
+	//zremrangebyscore name start end Delete the elements of the zset which have score in the range [start,end].
+	self.zremrangebyscore = function(name, start, end, callback){
+		self.request('zremrangebyscore', [name, parseInt(start), parseInt(end)], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				callback(err, parseInt(resp[1]));				
+			}
+		});
+	}
+	
+	//multi_zset name key1 score1 key2 score2 ... Set multiple key-score pairs(kvs) of a zset in one method call.
+	self.multi_zset = function(name, ks, callback){
+		let nks = [];
+		if (name && ks){
+			nks.push( name );
+			
+			Object.keys(ks).forEach(function(k){
+				if (ks[k]){
+					nks.push( k );
+					nks.push( ks[k] );
+				}
+			});
+		}
+		self.request('multi_zset', nks, function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				callback(err);
+			}
+		});
+	}
+	
+	//multi_zdel name key1 key2 ... Delete specified multiple keys of a zset.
+	self.multi_zdel = function(name, k, callback){
+		k.unshift( name );
+		self.request('multi_zdel', k, function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				callback(err);
+			}
+		});
+	}
+	
+	//multi_zget name key1 key2 ... Get the values related to the specified multiple keys of a zset.
+	self.multi_zget = function(name, k, callback){
+		k.unshift( name );
+		self.request('multi_zget', k, function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				var data = {};
+				for(var i=1; i<resp.length; i+=2){
+					data[ resp[i].toString() ] = parseInt(resp[i+1]);
+				}
+				callback(err, data);
+			}
+		});
+	}
+	
+	//zrange name offset limit Returns a range of key-score pairs by index range [offset, offset + limit).
+	self.zrange = function(name, offset, limit, callback){
+		if (typeof(limit) == 'function'){
+			callback = limit;
+			limit = 9223372036854775807;
+		}
+		self.request('zrange', [name, parseInt(offset), parseInt(limit)], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				var data = {};
+				for(var i=1; i<resp.length; i+=2){
+					data[ resp[i].toString() ] = parseInt(resp[i+1]);
+				}
+				callback(err, data);
+			}
+		});
+	}
+	
+	//zrrange name offset limit Returns a range of key-score pairs by index range [offset, offset + limit), in reverse order.
+	self.zrrange = function(name, offset, limit, callback){
+		if (typeof(limit) == 'function'){
+			callback = limit;
+			limit = 9223372036854775807;
+		}
+		self.request('zrrange', [name, parseInt(offset), parseInt(limit)], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				var data = {};
+				for(var i=1; i<resp.length; i+=2){
+					data[ resp[i].toString() ] = parseInt(resp[i+1]);
+				}
+				callback(err, data);
+			}
+		});
+	}
+	
+	////////////////// Hash
+
+	// callback(val)
+	self.hget = function(name, key, callback){
+		self.request('hget', [name, key], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				if(resp.length == 2){
+					callback(err, resp[1]);
+				}else{
+					callback('error');
+				}
+			}
+		});
+	}
+
+	// callback(err);
+	self.hset = function(name, key, val, callback){
+		self.request('hset', [name, key, val], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				callback(err);
+			}
+		});
+	}
+
+	// callback(err);
+	self.hdel = function(name, key, callback){
+		self.request('hdel', [name, key], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				callback(err);
+			}
+		});
+	}
+
+	// callback(err, {index:[], items:{key:score}})
+	self.hscan = function(name, key_start, key_end, limit, callback){
+		self.request('hscan', [name, key_start, key_end, limit], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				if(resp.length % 2 != 1){
+					callback('error');
+				}else{
+					var data = {};
+					for(var i=1; i<resp.length; i+=2){
+						data[ resp[i].toString() ] = resp[i+1].toString();
+					}
+					callback(err, data);
+				}
+			}
+		});
+	}
+
+	// callback(err, [])
+	self.hlist = function(name_start, name_end, limit, callback){
+		if (typeof(limit) == 'function'){
+			callback = limit;
+			limit = 9223372036854775807; //max elements at hash
+		}
+		self.request('hlist', [name_start, name_end, limit], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				var data = [];
+				for(var i=1; i<resp.length; i++){
+
+					data.push( resp[i].toString() );
+				}
+				callback(err, data);
+			}
+		});
+	}
+
+	// callback(size)
+	self.hsize = function(name, callback){
+		self.request('hsize', [name], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				if(resp.length == 2){
+					var size = parseInt(resp[1]);
+					callback(err, size);
+				}else{
+					var score = 0;
+					callback('error');
+				}
+			}
+		});
+	}
+	
+	//hclear name Delete all keys in a hashmap.
+	self.hclear = function(key, callback){
+		self.request('hclear', [key], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				callback(err);
+			}
+		});
+	}
+	
+	//hgetall name Returns the whole hash, as an array of strings indexed by strings.	
+	self.hgetall = function(key, callback){
+		self.request('hgetall', [key], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				var data = {};
+				for(var i=1; i<resp.length; i+=2){
+					data[ resp[i].toString() ] = resp[i+1].toString();
+				}
+				callback(err, data);
+			}
+		});
+	}
+	
+	//hexists name key Verify if the specified key exists in a hashmap.
+	self.hexists = function(name, key, callback){
+		self.request('hexists', [name, key], function(resp){
+			if(callback){
+				let err = resp[0] == 'ok'? 0 : resp[0];
+				let res = parseInt( resp[1].toString() );
+				
+				if (res === 0) res = false; else res = true;
+				
+				callback(err, res);
+			}
+		});
+	}
+	
+	//hincr name key [num] Increment the number stored at key in a hashmap by num
+	self.hincr = function(name, key, num, callback){
+		if (typeof(num) == 'function'){
+			callback = num;
+			num = 1;
+		}
+					
+		self.request('hincr', [name, key, num], function(resp){
+			if(callback){
+				let err = resp[0] == 'ok'? 0 : resp[0];
+		
+				callback(err, parseInt( resp[1].toString() ));
+			}
+		});
+	}
+	
+	//hrlist name_start name_end limit List hashmap names in range (name_start, name_end].
+	self.hrlist = function(name_start, name_end, limit, callback){
+		if (typeof(limit) == 'function'){
+			callback = limit;
+			limit = 9223372036854775807; //max elements at hash
+		}
+		
+		self.request('hrlist', [name_start, name_end, limit], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				var data = [];
+				for(var i=1; i<resp.length; i++){
+					data.push( resp[i].toString() );
+				}
+				callback(err, data);
+			}
+		});
+	}
+	
+	//hkeys name key_start key_end List keys of a hashmap in range (key_start, key_end].
+	self.hkeys = function(name, key_start, key_end, limit, callback){
+		if (typeof(limit) == 'function'){
+			callback = limit;
+			limit = 9223372036854775807; //max elements at hash
+		}		
+		
+		self.request('hkeys', [name, key_start, key_end, limit], function(resp){			
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				var data = [];
+				for(var i=1; i<resp.length; i++){
+					data.push( resp[i].toString() );
+				}
+				callback(err, data);
+			}
+		});
+	}
+	
+	//hrscan name key_start key_end limit List key-value pairs with keys in range (key_start, key_end], in reverse order.
+	self.hrscan = function(name, key_start, key_end, limit, callback){
+		if (typeof(limit) == 'function'){
+			callback = limit;
+			limit = 9223372036854775807; //max elements at hash
+		}
+		
+		self.request('hrscan', [name, key_start, key_end, limit], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				if(resp.length % 2 != 1){
+					callback('error');
+				}else{
+					var data = {};
+					for(var i=1; i<resp.length; i+=2){
+						data[ resp[i].toString() ] = resp[i+1].toString();
+					}
+					callback(err, data);
+				}
+			}
+		});
+	}
+	
+	//multi_hget name key1 key2 ... Get the values related to the specified multiple keys of a hashmap.
+	self.multi_hget = function(name, keys, callback){
+		if (name && keys && keys.length)
+			keys.unshift( name );
+				
+		self.request('multi_hget', keys, function(resp){
+	
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				var data = {};
+				for(var i=1; i<resp.length; i+=2){
+					data[ resp[i].toString() ] = resp[i+1].toString();
+				}
+				callback(err, data);
+			}
+		});
+	}
+	
+	//multi_hdel name key1 key2 ... Delete specified multiple keys in a hashmap.
+	self.multi_hdel = function(name, keys, callback){
+		if (name && keys && keys.length)
+			keys.unshift( name );
+				
+		self.request('multi_hdel', keys, function(resp){
+	
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];				
+				callback(err);
+			}
+		});
+	}
+	
+	//multi_hset name key1 value1 key2 value2 ... Set multiple key-value pairs(kvs) of a hashmap in one method call.
+	self.multi_hset = function(name, kv, callback){
+		let nkv = [];
+		if (name && kv){
+			nkv.push( name );
+			
+			Object.keys(kv).forEach(function(k){
+				if (kv[k]){
+					nkv.push( k );
+					nkv.push( kv[k] );
+				}
+			});
+		}
+				
+		self.request('multi_hset', nkv, function(resp){
+	
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];				
+				callback(err);
+			}
+		});
+	}
+	
+	
+	////////////////// List
+	
+	//qpush_front name item1 item2 ... Adds one or more than one element to the head of the queue.
+	self.qpush_front = function(name, v, callback){
+		console.log( typeof(v) );
+		
+		if (typeof(v) == 'array')
+			v.unshift( name );
+		else
+			v = [name, v];
+						
+		self.request('qpush_front', v, function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];				
+				callback(err, parseInt( resp[1].toString() ));
+			}
+		});
+	}
+	
+	//qpush name item1 item2 ... Alias of `qpush_back`.
+	self.qpush = function(name, v, callback){
+		self.qpush_front(name, v, callback);
+	}
+	
+	//qpush_back name item1 item2 ... Adds an or more than one element to the end of the queue.
+	self.qpush_back = function(name, v, callback){
+		if (typeof(v) == 'array')
+			v.unshift( name );
+		else
+			v = [name, v];
+						
+		self.request('qpush_back', v, function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];				
+				callback(err, parseInt( resp[1].toString() ));
+			}
+		});
+	}
+	
+	//qpop_front name size Pop out one or more elements from the head of a queue.
+	self.qpop_front = function(name, size, callback){
+		size = parseInt(size);
+						
+		self.request('qpop_front', [name, size], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];		
+				var data = [];
+				for(var i=1; i<resp.length; i++){
+					data.push( resp[i].toString() );
+				}
+				callback(err, data);
+			}
+		});
+	}
+	
+	//qpop name size Alias of `qpop_front`.
+	self.qpop = function(name, size, callback){
+		self.qpop_front(name, size, callback);
+	}
+	
+	//qpop_back name size Pop out one or more elements from the tail of a queue.
+	self.qpop_back = function(name, size, callback){
+		size = parseInt(size);
+						
+		self.request('qpop_back', [name, size], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];		
+				var data = [];
+				for(var i=1; i<resp.length; i++){
+					data.push( resp[i].toString() );
+				}
+				callback(err, data);
+			}
+		});
+	}
+
+	//qfront name Returns the first element of a queue.
+	self.qfront = function(name, callback){
+		self.request('qfront', [name], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];		
+				
+				callback(err, resp[1].toString());
+			}
+		});
+	}
+	
+	//qback name Returns the last element of a queue.
+	self.qback = function(name, callback){
+		self.request('qback', [name], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];		
+				
+				callback(err, resp[1].toString());
+			}
+		});
+	}
+	
+	//qsize name Returns the number of items in the queue.
+	self.qsize = function(name, callback){
+		self.request('qsize', [name], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];		
+				
+				callback(err, parseInt(resp[1].toString()));
+			}
+		});
+	}
+
+	//qclear name Clear the queue.
+	self.qclear = function(name, callback){
+		self.request('qclear', [name], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];		
+				
+				callback(err);
+			}
+		});
+	}
+
+	//qget name index Returns the element a the specified index(position).
+	self.qget = function(name, index, callback){
+		self.request('qget', [name, parseInt(index)], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];		
+				
+				callback(err, resp[1].toString());
+			}
+		});
+	}
+	
+	//qset name index val Description
+	self.qset = function(name, index, val, callback){
+		self.request('qset', [name, parseInt(index), val], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];		
+				
+				callback(err, resp[1].toString());
+			}
+		});
+	}
+	
+	//qrange name offset limit Returns a portion of elements from the queue at the specified range [offset, offset + limit].
+	self.qrange = function(name, offset, limit, callback){
+		limit = parseInt(limit);
+		offset = parseInt(offset);
+		
+		self.request('qrange', [name, offset, limit], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];		
+				var data = [];
+				for(var i=1; i<resp.length; i++){
+					data.push( resp[i].toString() );
+				}
+				callback(err, data);
+			}
+		});
+	}
+	
+	//qslice name begin end Returns a portion of elements from the queue at the specified range [begin, end].
+	self.qslice = function(name, offset, limit, callback){
+		limit = parseInt(limit);
+		offset = parseInt(offset);
+		
+		self.request('qslice', [name, offset, limit], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];		
+				var data = [];
+				for(var i=1; i<resp.length; i++){
+					data.push( resp[i].toString() );
+				}
+				callback(err, data);
+			}
+		});
+	}
+
+	//qtrim_front name size Remove multi elements from the head of a queue.
+	self.qtrim_front = function(name, size, callback){
+		self.request('qtrim_front', [name, parseInt(size)], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];		
+				
+				callback(err, parseInt(resp[1].toString()));
+			}
+		});
+	}
+	
+	//qtrim_back name size Remove multi elements from the tail of a queue.
+	self.qtrim_back = function(name, size, callback){
+		self.request('qtrim_back', [name, parseInt(size)], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];		
+				
+				callback(err, parseInt(resp[1].toString()));
+			}
+		});
+	}
+
+	//qlist name_start name_end limit List list/queue names in range (name_start, name_end].
+	self.qlist = function(name_start, name_end, limit, callback){
+		if (typeof(limit) == 'function'){
+			callback = limit;
+			limit = 9223372036854775807;
+		}
+		
+		self.request('qlist', [name_start, name_end, limit], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];		
+				var data = [];
+				for(var i=1; i<resp.length; i++){
+					data.push( resp[i].toString() );
+				}
+				callback(err, data);
+			}
+		});
+	}
+	
+	//qrlist name_start name_end limit List list/queue names in range (name_start, name_end], in reverse order.
+	self.qrlist = function(name_start, name_end, limit, callback){
+		if (typeof(limit) == 'function'){
+			callback = limit;
+			limit = 9223372036854775807;
+		}
+		
+		self.request('qrlist', [name_start, name_end, limit], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];		
+				var data = [];
+				for(var i=1; i<resp.length; i++){
+					data.push( resp[i].toString() );
+				}
+				callback(err, data);
+			}
+		});
+	}
+
+	
+	////////////////// Server command
+	
+	//auth password Authenticate the connection.
+	self.auth = function(passw, callback){
+		self.request('auth', [passw], function(resp){
+			if(callback){
+				let err = resp[0] == 'ok'? 0 : resp[0];
+								
+				callback(err);
+			}
+		});
+	}
+	
+	//dbsize Return the approximate size of the database. In bytes
+	self.dbsize = function(callback){	
+		self.request('dbsize', [name, key, num], function(resp){
+			if(callback){
+				let err = resp[0] == 'ok'? 0 : resp[0];
+		
+				callback(err, parseInt( resp[1].toString() ));
+			}
+		});
+	}
+	
+	//flushdb [type] Delete all data in ssdb server.
+	self.flushdb = function(type, callback){	
+		if (!type)	type = '';
+		if (['', 'kv', 'hash', 'zset', 'list'].indexOf(type) == -1) type = '';
+		
+		self.request('flushdb', [type], function(resp){
+			if(callback){
+				let err = resp[0] == 'ok'? 0 : resp[0];
+		
+				callback(err);
+			}
+		});
+	}
+	
+	//info [opt] Return the information of server.
+	self.info = function(opt, callback){
+		if (!opt) opt = '';
+		self.request('info', [opt], function(resp){
+			if(callback){
+				var err = resp[0] == 'ok'? 0 : resp[0];
+				var data = [];
+				
+				for(var i=1; i<resp.length; i++){
+					var k = resp[i].toString();
+					data.push(k);
+				}
+				
+				callback(err, data);
+			}
+		});
+	}
+	
+	//slaveof id host port [auth last_seq last_key] Start a replication slave.
+	self.slaveof = function(id, host, port, auth, last_seq, last_key, callback){	
+		if (!last_seq)	last_seq = '';
+		if (!last_key)	last_key = '';
+		if (!auth)	auth = '';
+		if (!port)	port = 8888;
+				
+		self.request('slaveof', [id, host, port, auth, last_seq, last_key], function(resp){
+			if(callback){
+				let err = resp[0] == 'ok'? 0 : resp[0];
+		
+				callback(err);
+			}
+		});
+	}
+
+
+	////////////////// IP Filter  @todo
+	
+
+	
+	
 
 	return self;
 }
diff --git a/package.json b/package.json
index 1974c72..2316c1a 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "nodessdb",
-  "version": "1.0.0",
+  "version": "1.0.3",
   "description": "SSDB nodejs Client",
   "main": "SSDB.js",
   "scripts": {