Queue commands sent before a connection is available.

index.js

@@ -17,6 +17,7 @@ function RedisReplyParser() {
 }
 sys.inherits(RedisReplyParser, events.EventEmitter);
 
+// Buffer.toString() is quite slow for small strings
 function small_toString(buf) {
     var tmp = "", i = 0, end = buf.end;
     
@@ -280,7 +281,8 @@ function RedisClient(stream) {
     this.connected = false;
     this.connections = 0;
     this.attempts = 1;
-    this.command_queue = new Queue;
+    this.command_queue = new Queue(); // holds sent commands to de-pipeline them
+    this.offline_queue = new Queue(); // holds commands issued but not able to be sent
     this.commands_sent = 0;
     this.retry_delay = 250;
     this.retry_backoff = 1.7;
@@ -307,6 +309,15 @@ function RedisClient(stream) {
         self.stream.setNoDelay();
         self.stream.setTimeout(0);
 
+        var command_obj;
+        while (self.offline_queue.length > 0) {
+            command_obj = self.offline_queue.shift();
+            if (exports.debug_mode) {
+                console.log("Sending offline command: " + command_obj.command);
+            }
+            self.send_command(command_obj.command, command_obj.args, command_obj.callback);
+        }
+        
         self.emit("connect");
     });
     
@@ -318,6 +329,12 @@ function RedisClient(stream) {
         if (exports.debug_mode) {
             console.warn("Connecting to redis server: " + msg);
         }
+        self.offline_queue.forEach(function (args) {
+            if (typeof args[2] === "function") {
+                args[2]("Server connection could not be established");
+            }
+        });
+        
         self.connected = false;
         self.emit("error", msg);
     });
@@ -404,7 +421,7 @@ RedisClient.prototype.return_reply = function (reply_buffer) {
 };
 
 RedisClient.prototype.send_command = function () {
-    var command, callback, args, this_args;
+    var command, callback, args, this_args, command_obj;
 
     this_args = Array.prototype.slice.call(arguments); // convert arguments into real array
 
@@ -427,17 +444,21 @@ RedisClient.prototype.send_command = function () {
         throw new Error("First argument of send_command must be the command name");
     }
 
-    if (! this.connected) {
-        // TODO - queue this command and send it once we are connected.
-        callback(new Error("Redis client is not connected"));
-        return;
-    }
-
-    this.command_queue.push({
+    command_obj = {
         command: command,
         args: args,
         callback: callback
-    });
+    };
+
+    if (! this.connected) {
+        if (exports.debug_mode) {
+            console.log("Queueing " + command + " for next server connection.");
+        }
+        this.offline_queue.push(command_obj);
+        return;
+    }
+
+    this.command_queue.push(command_obj);
     this.commands_sent += 1;
 
     var elem_count = 1, stream = this.stream, buffer_args = false, command_str = "";
@@ -461,6 +482,7 @@ RedisClient.prototype.send_command = function () {
         if (exports.debug_mode) {
             console.log("send command: " + command_str);
         }
+        // Need to catch "Stream is not writable" exception here and error everybody in the command queue out
         stream.write(command_str);
     } else {
         if (exports.debug_mode) {