Implement an optional lightweight protocol reader.

CHANGELOG

@@ -7,6 +7,10 @@ v0.6.6 (2011-xx-xx)
   * Some performance improvements for multibulk replies (parsing them is about 
     16% faster than the previous version).
 
+  * Added a new and optional protocol reader, more lightweight and faster than 
+    the default handlers-based one. Users can also specify a custom protocol 
+    reader using the new 'reader' client option.
+
   * Added support for connecting to Redis using UNIX domain sockets (ISSUE #25).
 
   * The "read_write_timeout" connection parameter can now be set to 0 or false 

lib/Predis.php

@@ -76,22 +76,16 @@ class Client {
     }
 
     private function setupClient($options) {
-        $this->_responseReader = new ResponseReader();
-        $this->_options = self::filterClientOptions($options);
-
-        $this->setProfile($this->_options->profile);
-        if ($this->_options->iterable_multibulk === true) {
-            $this->_responseReader->setHandler(
-                Protocol::PREFIX_MULTI_BULK,
-                new ResponseMultiBulkStreamHandler()
-            );
-        }
-        if ($this->_options->throw_on_error === false) {
-            $this->_responseReader->setHandler(
-                Protocol::PREFIX_ERROR,
-                new ResponseErrorSilentHandler()
-            );
-        }
+        $options = self::filterClientOptions($options);
+
+        $this->setProfile($options->profile);
+
+        $reader = $options->reader;
+        $reader->setOption('iterable_multibulk', $options->iterable_multibulk);
+        $reader->setOption('throw_on_error', $options->throw_on_error);
+
+        $this->_options = $options;
+        $this->_responseReader = $reader;
     }
 
     private function setupConnection($parameters) {
@@ -355,6 +349,28 @@ class ClientOptionsThrowOnError implements IClientOptionsHandler {
     }
 }
 
+class ClientOptionsReader implements IClientOptionsHandler {
+    public function validate($option, $value) {
+        if ($value instanceof \Predis\IResponseReader) {
+            return $value;
+        }
+        if (is_string($value)) {
+            if ($value === 'fast') {
+                return new \Predis\FastResponseReader();
+            }
+            $valueReflection = new \ReflectionClass($value);
+            if ($valueReflection->isSubclassOf('\Predis\Distribution\IDistributionStrategy')) {
+                return new $value;
+            }
+        }
+        throw new \InvalidArgumentException("Invalid value for option $option");
+    }
+
+    public function getDefault() {
+        return new \Predis\ResponseReader();
+    }
+}
+
 class ClientOptions {
     private static $_optionsHandlers;
     private $_options;
@@ -376,6 +392,7 @@ class ClientOptions {
             'key_distribution' => new \Predis\ClientOptionsKeyDistribution(),
             'iterable_multibulk' => new \Predis\ClientOptionsIterableMultiBulk(),
             'throw_on_error' => new \Predis\ClientOptionsThrowOnError(),
+            'reader' => new \Predis\ClientOptionsReader(),
         );
     }
 
@@ -661,7 +678,95 @@ class ResponseIntegerHandler implements IResponseHandler {
     }
 }
 
-class ResponseReader {
+interface IResponseReader {
+    public function read(Connection $connection);
+    public function setOption($option, $value);
+    public function getOption($option);
+}
+
+class FastResponseReader implements IResponseReader {
+    private $_iterableMultibulk, $_throwErrors;
+
+    public function __construct() {
+        $this->_iterableMultibulk = false;
+        $this->_throwErrors = true;
+    }
+
+    public function read(Connection $connection) {
+        $chunk = $connection->readLine();
+        $prefix = $chunk[0];
+        $payload = substr($chunk, 1);
+        switch ($prefix) {
+            case '+':    // inline
+                switch ($payload) {
+                    case 'OK':
+                        return true;
+                    case 'QUEUED':
+                        return new ResponseQueued();
+                    default:
+                        return $payload;
+                }
+
+            case '$':    // bulk
+                $size = (int) $payload;
+                if ($size === -1) {
+                    return null;
+                }
+                return substr($connection->readBytes($size + 2), 0, -2);
+
+            case '*':    // multi bulk
+                $count = (int) $payload;
+                if ($count === -1) {
+                    return null;
+                }
+                if ($this->_iterableMultibulk) {
+                    return new MultiBulkResponseSimple($connection, $count);
+                }
+                $multibulk = array();
+                for ($i = 0; $i < $count; $i++) {
+                    $multibulk[$i] = $this->read($connection);
+                }
+                return $multibulk;
+
+            case ':':    // integer
+                return (int) $payload;
+
+            case '-':    // error
+                $errorMessage = substr($payload, 4);
+                if ($this->_throwErrors) {
+                    throw new ServerException($errorMessage);
+                }
+                return new ResponseError($errorMessage);
+
+            default:
+                throw new CommunicationException(
+                    $connection, "Unknown prefix: '$prefix'"
+                );
+        }
+    }
+
+    public function setOption($option, $value) {
+        switch ($option) {
+            case 'iterable_multibulk':
+                $this->_iterableMultibulk = (bool) $value;
+                break;
+            case 'throw_on_error':
+                $this->_throwErrors = (bool) $value;
+                break;
+        }
+    }
+
+    public function getOption($option) {
+        switch ($option) {
+            case 'iterable_multibulk':
+                return $this->_iterableMultibulk;
+            case 'throw_on_error':
+                return $this->_throwErrors;
+        }
+    }
+}
+
+class ResponseReader implements IResponseReader {
     private $_prefixHandlers;
 
     public function __construct() {
@@ -707,6 +812,28 @@ class ResponseReader {
             $connection, $message
         ));
     }
+
+    public function setOption($option, $value) {
+        switch ($option) {
+            case 'iterable_multibulk':
+                $handler = $value ? 'Predis\ResponseMultiBulkStreamHandler' : 'Predis\ResponseMultiBulkHandler';
+                $this->_prefixHandlers[Protocol::PREFIX_MULTI_BULK] = new $handler();
+                break;
+            case 'throw_on_error':
+                $handler = $value ? 'Predis\ResponseErrorHandler' : 'Predis\ResponseErrorSilentHandler';
+                $this->_prefixHandlers[Protocol::PREFIX_ERROR] = new $handler();
+                break;
+        }
+    }
+
+    public function getOption($option) {
+        switch ($option) {
+            case 'iterable_multibulk':
+                return $this->_prefixHandlers[Protocol::PREFIX_MULTI_BULK] instanceof ResponseMultiBulkStreamHandler;
+            case 'throw_on_error':
+                return $this->_prefixHandlers[Protocol::PREFIX_ERROR] instanceof ResponseErrorHandler;
+        }
+    }
 }
 
 class ResponseError {
@@ -1317,7 +1444,7 @@ interface IConnection {
 class Connection implements IConnection {
     private $_params, $_socket, $_initCmds, $_reader, $_initializer;
 
-    public function __construct(ConnectionParameters $parameters, ResponseReader $reader = null) {
+    public function __construct(ConnectionParameters $parameters, IResponseReader $reader = null) {
         $scheme = $parameters->scheme;
         if ($scheme !== 'redis' && $scheme !== 'tcp' && $scheme !== 'unix') {
             throw new \InvalidArgumentException("Invalid scheme: $scheme");