Handle MULTI and various error permutations.

redis.js

@@ -21,6 +21,7 @@ RedisReplyParser.prototype.execute = function (incoming_buf) {
     var pos = 0;
 
     while (pos < incoming_buf.length) {
+//        console.log("execute " + this.state + " " + pos + " " + String.fromCharCode(incoming_buf[pos]));
         switch (this.state) {
         case "type":
             this.type = incoming_buf[pos];
@@ -53,7 +54,7 @@ RedisReplyParser.prototype.execute = function (incoming_buf) {
             break;
         case "integer line":
             if (incoming_buf[pos] === 13) {
-                this.emit("integer reply", this.return_buffer.slice(0, this.return_buffer.end));
+                this.send_reply(parseInt(this.return_buffer.slice(0, this.return_buffer.end)),10);
                 this.state = "final lf";
             } else {
                 this.return_buffer[this.return_buffer.end] = incoming_buf[pos];
@@ -64,7 +65,7 @@ RedisReplyParser.prototype.execute = function (incoming_buf) {
             break;
         case "error line":
             if (incoming_buf[pos] === 13) {
-                this.emit("error reply", new Error(this.return_buffer.slice(0, this.return_buffer.end)));
+                this.send_error(this.return_buffer.toString("utf8", 0, this.return_buffer.end));
                 this.state = "final lf";
             } else {
                 this.return_buffer[this.return_buffer.end] = incoming_buf[pos];
@@ -74,7 +75,7 @@ RedisReplyParser.prototype.execute = function (incoming_buf) {
             break;
         case "single line":
             if (incoming_buf[pos] === 13) {
-                this.emit("single line reply", this.return_buffer.slice(0, this.return_buffer.end));
+                this.send_reply(this.return_buffer.toString("utf8", 0, this.return_buffer.end));
                 this.state = "final lf";
             } else {
                 this.return_buffer[this.return_buffer.end] = incoming_buf[pos];
@@ -95,7 +96,7 @@ RedisReplyParser.prototype.execute = function (incoming_buf) {
         case "multi bulk count lf":
             if (incoming_buf[pos] === 10) { // \n
                 this.multi_bulk_length = parseInt(this.tmp_buffer.toString("utf8", 0, this.tmp_buffer.end), 10);
-                this.multi_bulk_responses = [];
+                this.multi_bulk_replies = [];
                 this.state = "type";
             } else {
                 this.emit("error", new Error("didn't see LF after NL reading multi bulk count"));
@@ -117,11 +118,7 @@ RedisReplyParser.prototype.execute = function (incoming_buf) {
             if (incoming_buf[pos] === 10) { // \n
                 this.bulk_length = parseInt(this.tmp_buffer.toString("utf8", 0, this.tmp_buffer.end), 10);
                 if (this.bulk_length === -1) {
-                    if (this.multi_bulk_length > 0) {
+                    this.send_reply(null);
-                        this.add_multi_bulk_response(null);
-                    } else {
-                        this.emit("null reply");
-                    }
                     this.state = "type";
                 } else {
                     this.state = "bulk data";
@@ -143,13 +140,10 @@ RedisReplyParser.prototype.execute = function (incoming_buf) {
             this.return_buffer.end += 1;
             pos += 1;
             if (this.return_buffer.end === this.bulk_length) {
-                if (this.multi_bulk_length > 0) {
+                // this ugilness could go away if we gave the user a volatile buffer, but that seems dangerous
-                    var mb_tmp = new Buffer(this.bulk_length);
+                var bd_tmp = new Buffer(this.bulk_length);
-                    this.return_buffer.copy(mb_tmp, 0, 0, this.bulk_length);
+                this.return_buffer.copy(bd_tmp, 0, 0, this.bulk_length);
-                    this.add_multi_bulk_response(mb_tmp);
+                this.send_reply(bd_tmp);
-                } else {
-                    this.emit("bulk reply", this.return_buffer.slice(0, this.bulk_length));
-                }
                 this.state = "final cr";
             }
             break;
@@ -179,12 +173,29 @@ RedisReplyParser.prototype.execute = function (incoming_buf) {
     }
 };
 
-RedisReplyParser.prototype.add_multi_bulk_response = function (response) {
+RedisReplyParser.prototype.send_error = function (reply) {
-    this.multi_bulk_responses.push(response);
+    if (this.multi_bulk_length > 0) {
-    if (this.multi_bulk_responses.length === this.multi_bulk_length) {
+        // TODO - can this happen?  Seems like maybe not.
-        this.emit("multibulk reply", this.multi_bulk_responses);
+        this.add_multi_bulk_reply(reply);
+    } else {
+        this.emit("reply error", reply);
+    }
+}
+
+RedisReplyParser.prototype.send_reply = function (reply) {
+    if (this.multi_bulk_length > 0) {
+        this.add_multi_bulk_reply(reply);
+    } else {
+        this.emit("reply", reply);
+    }
+};
+
+RedisReplyParser.prototype.add_multi_bulk_reply = function (reply) {
+    this.multi_bulk_replies.push(reply);
+    if (this.multi_bulk_replies.length === this.multi_bulk_length) {
+        this.emit("reply", this.multi_bulk_replies);
         this.multi_bulk_length = 0;
-        this.multi_bulk_responses = null;
+        this.multi_bulk_replies = null;
     }
 };
 
@@ -194,69 +205,99 @@ function RedisClient(stream) {
     this.stream = stream;
     this.connected = false;
     this.connections = 0;
-    this.commands_sent = 0;
+    this.attempts = 1;
-    this.commands_in_flight = 0;
-    this.replies_received = 0;
     this.command_queue = [];
+    this.commands_sent = 0;
+    this.retry_delay = 250;
+    this.retry_backoff = 1.7;
 
     var self = this;
 
-    stream.on("connect", function () {
+    this.stream.on("connect", function () {
-        self.on_connect();
+        self.connected = true;
+        self.connections += 1;
+        self.command_queue = [];
+
+        self.reply_parser = new RedisReplyParser();
+        self.reply_parser.on("reply error", function (reply) {
+            self.return_error(reply);
+        });
+        self.reply_parser.on("reply", function (reply) {
+            self.return_reply(reply);
+        });
+        self.reply_parser.on("error", function (err) {
+            console.log("Redis reply parser error: " + err.stack);
         });
 
-    stream.on("data", function (buffer_from_socket) {
+        self.retry_delay = 250;
+        self.stream.setNoDelay();
+        self.stream.setTimeout(0);
+
+        self.emit("connect");
+    });
+    
+    this.stream.on("data", function (buffer_from_socket) {
         self.on_data(buffer_from_socket);
     });
 
-    stream.on("error", function () {
+    this.stream.on("error", function (msg) {
-        console.log("Error connecting to redis server.");
+        if (exports.debug_mode) {
+            console.warn("Connecting to redis server: " + msg);
+        }
+        self.connected = false;
+        self.emit("error", msg);
     });
-    stream.on("close", function () {
+
-        console.log("Close on redis connection.");
+    this.stream.on("close", function () {
+        self.connection_gone();
     });
-    stream.on("end", function () {
+
-        console.log("End on redis connection.");
+    this.stream.on("end", function () {
+        self.connection_gone();
     });
     
     events.EventEmitter.call(this);
 }
 sys.inherits(RedisClient, events.EventEmitter);
 
-RedisClient.prototype.on_connect = function () {
+RedisClient.prototype.connection_gone = function () {
-    console.log("Got connection.");
-    
-    this.connected = true;
-    this.connections += 1;
-    
-    this.reply_parser = new RedisReplyParser();
     var self = this;
-    this.reply_parser.on("error reply", function (err) {
+
-        self.return_error(err);
+    if (self.retry_timer) {
+        return;
+    }
+
+    if (exports.debug_mode) {
+        console.warn("Redis connection is gone.");
+    }
+    self.connected = false;
+    self.emit("close");
+    self.command_queue.forEach(function (args) {
+        if (typeof args[2] === "function") {
+            args[2]("Server connection closed");
+        }
     });
-    this.reply_parser.on("null reply", function () {
+    if (exports.debug_mode) {
-        self.return_reply(null);
+        console.log("Retry conneciton in " + self.retry_delay + " ms");
-    });
+    }
-    this.reply_parser.on("integer reply", function (response_buffer) {
+    self.attempts += 1;
-        self.return_reply(parseInt(response_buffer.toString(), 10));
+    self.emit("reconnecting", "delay " + self.retry_delay + ", attempt " + self.attempts);
-    });
+    self.retry_timer = setTimeout(function () {
-    this.reply_parser.on("bulk reply", function (response_buffer) {
+        if (exports.debug_mode) {
-        self.return_reply(response_buffer);
+            console.log("Retrying conneciton...");
-    });
+        }
-    this.reply_parser.on("multibulk reply", function (response_list) {
+        self.retry_timer = null;
-        self.return_reply(response_list);
+        self.retry_delay = self.retry_delay * self.retry_backoff;
-    });
+        self.stream.destroy();
-    this.reply_parser.on("single line reply", function (response_buffer) {
+        self.stream.connect(self.port, self.host);
-        self.return_reply(response_buffer.toString());
+    }, self.retry_delay);
-    });
+}
-    this.reply_parser.on("error", function (err) {
-        console.log("Redis parser had an error: " + err.stack);
-    });
-    this.emit("connect");
-};
 
 RedisClient.prototype.on_data = function (data) {
+    if (exports.debug_mode) {
         console.log("on_data: " + data.toString());
+    }
+    
     try {
         this.reply_parser.execute(data);
     } catch (err) {
@@ -267,14 +308,25 @@ RedisClient.prototype.on_data = function (data) {
 RedisClient.prototype.return_error = function (err) {
     var command_obj = this.command_queue.shift();
 
-    console.log("Error on " + command_obj.command + " " + command_obj.args + ": " + err);
+    if (command_obj && typeof command_obj.callback === "function") {
         command_obj.callback(err);
+    } else {
+        console.log("no callback to send error: " + err.stack);
+        // this will probably not make it anywhere useful, but we might as well try
+        throw err;
+    }
 }
 
-RedisClient.prototype.return_reply = function (response_buffer) {
+RedisClient.prototype.return_reply = function (reply_buffer) {
     var command_obj = this.command_queue.shift();
     
-    command_obj.callback(null, response_buffer);
+    if (command_obj && typeof command_obj.callback === "function") {
+        command_obj.callback(null, reply_buffer);
+    } else {
+        if (this.debug_mode) {
+            console.log("no callback for reply: " + reply_buffer.toString());
+        }
+    }
 };
 
 RedisClient.prototype.send_command = function (command, args, callback) {
@@ -288,8 +340,8 @@ RedisClient.prototype.send_command = function (command, args, callback) {
         return;
     }
 
-    if (typeof callback !== "function") {
+    if (callback !== undefined && typeof callback !== "function") {
-        throw new Error("Third argument of send_command must a results callback function");
+        throw new Error("Third argument of send_command must a results callback function, or omitted");
         return;
     }
 
@@ -303,6 +355,7 @@ RedisClient.prototype.send_command = function (command, args, callback) {
         args: args,
         callback: callback
     });
+    this.commands_sent += 1;
 
     var elem_count = 1, stream = this.stream, buffer_args = false, command_str = "";
 
@@ -311,7 +364,7 @@ RedisClient.prototype.send_command = function (command, args, callback) {
         return arg instanceof Buffer;
     });
 
-    // Always use "Multi bulk commands", but if passed Buffer args, then do multiple writes for the args
+    // Always use "Multi bulk commands", but if passed any Buffer args, then do multiple writes, one for each arg
 
     command_str = "*" + elem_count + "\r\n$" + command.length + "\r\n" + command + "\r\n";
     
@@ -322,15 +375,16 @@ RedisClient.prototype.send_command = function (command, args, callback) {
             }
             command_str += "$" + arg.length + "\r\n" + arg + "\r\n";
         });
-//        console.log("non-buffer full command: " + command_str);
+        if (exports.debug_mode) {
-        if (stream.write(command_str) === false) {
+            console.log("send command: " + command_str);
-            console.log("Buffered write 0");
         }
+        stream.write(command_str);
     } else {
-        console.log("buffer command str: " + command_str);
+        if (exports.debug_mode) {
-        if (stream.write(command_str) === false) {
+            console.log("send command: " + command_str);
-            console.log("Buffered write 1");
+            console.log("send command has Buffer arguments");
         }
+        stream.write(command_str);
         
         args.forEach(function (arg) {
             if (arg.length === undefined) {
@@ -367,10 +421,6 @@ exports.commands = [
     "HSET", "HGET", "HMGET", "HMSET", "HINCRBY", "HEXISTS", "HDEL", "HLEN", "HKEYS", "HVALS", "HGETALL",
     // Sorting
     "SORT",
-    // Transactions
-    "MULTI", "EXEC", "DISCARD", "WATCH", "UNWATCH",
-    // Publish/Subscribe
-    "SUBSCRIBE", "UNSUBSCRIBE", "PUBLISH",
     // Persistence control commands
     "SAVE", "BGSAVE", "LASTSAVE", "SHUTDOWN", "BGREWRITEAOF",
     // Remote server control commands
@@ -386,6 +436,48 @@ exports.commands.forEach(function (command) {
     };
 });
 
+// Transactions
+// "MULTI", "EXEC", "DISCARD", "WATCH", "UNWATCH",
+// Publish/Subscribe
+// "SUBSCRIBE", "UNSUBSCRIBE", "PUBLISH",
+
+RedisClient.prototype.multi = function (commands) {
+    var self = this;
+
+    try {
+        this.send_command("MULTI", [], function (err, reply) {
+            if (err) {
+                console.warn("Error starting MULTI request: " + err.stack);
+            }
+        });
+        commands.forEach(function (args, command_num) {
+            self.send_command(args[0], args[1], function (err, reply) {
+                if (err) {
+                    args[2](err);
+                    commands.splice(command_num, 1); // what if this runs before all commands are sent?
+                } else {
+                    if (reply !== "QUEUED") {
+                        console.warn("Unexpected MULTI reply: " + reply + " instead of 'QUEUED'");
+                    }
+                }
+            });
+        });
+        this.send_command("EXEC", [], function (err, replies) {
+            replies.forEach(function (reply, reply_num) {
+                if (typeof commands[reply_num][2] === "function") {
+                    commands[reply_num][2](null, reply)
+                } else {
+                    if (exports.debug_mode) {
+                        console.log("no callback for multi response " + reply_num + ", skipping.");
+                    }
+                }
+            });
+        });
+    } catch (err) {
+        console.log("Caught exception in MULTI: " + err.stack);
+    }
+};
+
 exports.createClient = function (port_arg, host_arg, options) {
     var port = port_arg || default_port,
         host = host || default_host,
@@ -401,3 +493,10 @@ exports.createClient = function (port_arg, host_arg, options) {
     return red_client;
 };
 
+exports.print = function (err, reply) {
+    if (err) {
+        console.log("Error: " + err);
+    } else {
+        console.log("Reply: " + reply);
+    }
+};