Issue #2696129 by Jeremy: Add support for msgpack serialize/unserialize

README.txt

@@ -298,41 +298,55 @@ except for the 'cache_page' bin which will use the 'something_else_unique'
 prefix. Not that if using a keyed array for specifying prefix, you must specify
 the 'default' prefix.
 
-## EXPERIMENTAL - ALTERNATIVE SERIALIZE: IGBINARY ##
+## EXPERIMENTAL - ALTERNATIVE SERIALIZE ##
 
 This is a new experimental feature added to the memcache module in version
 7.x-1.6 and should be tested carefully before utilizing in production.
 
 To optimize how data is serialized before it is written to memcache, you can
-enable the igbinary PHP extension which converts from using PHP's human
-readable serialized data structures to a compact binary format. The igbinary
-documentation claims on average a 50% reducation in storage requirements,
-reducing the amount of traffic sent over the network. It goes on to explain:
-
-  "Unserialization performance is at least on par with the standard PHP
-   serializer.  Serialization performance depends on the 'compact_strings'
-   option which enables duplicate string tracking. String are inserted to a
-   hash table which adds some overhead. In usual scenarios this does not have
-   much significance since usage pattern is 'serialize rarely, unserialize
-   often'. With 'compact_strings' option igbinary is usually a bit slower
-   than the standard serializer. Without it, a bit faster."
-
-If the igbinary extension is enabled, the memcache modue will use it by
-default. You can verify which serialize function is being used by enabling the
-memcache_admin module and visiting admin/reports/memcache. To disable igbinary
-when the php extension is installed add the following to your settings.php and
-then restart all memcached daemons:
-
-$conf['memcache_enable_igbinary'] = FALSE;
-
-The project is maintained on GitHub:
+enable either the igbinary or msgpack PECL extension. Both switch from using
+PHP's own human-readable serialized data strucutres to more compact binary
+formats.
+
+No specicial configuration is required.  If both extensions are enabled,
+memcache will automatically use the igbinary extension. If only one extension
+is enabled, memcache will automatically use that extension.
+
+You can optionally specify which extension is used by adding one of the
+following to your settings.php:
+
+  // Force memcache to use PHP's core serialize functions
+  $conf['memcache_serialize'] = 'serialize';
+
+  // Force memcache to use the igbinary serialize functions (if available)
+  $conf['memcache_serialize'] = 'igbinary';
+
+  // Force memcache to use the msgpack serialize functions (if available)
+  $conf['memcache_serialize'] = 'msgpack';
+
+To review which serialize function is being used, enable the memcache_admin
+module and visit admin/reports/memcache.
+
+IGBINARY:
+
+The igbinary project is maintained on GitHub:
  - https://github.com/phadej/igbinary
 
-The official PECL package can be found at:
+The official igbinary PECL extension can be found at:
  - https://pecl.php.net/package/igbinary
 
 Version 2.0.1 or greater is recommended.
 
+MSGPACK:
+
+The msgpack project is maintained at:
+  - https://msgpack.org
+
+The official msgpack PECL extension can be found at:
+  - https://pecl.php.net/package/msgpack
+
+Version 2.0.2 or greater is recommended.
+
 ## MAXIMUM LENGTHS ##
 
 If the length of your prefix + key + bin combine to be more than 250 characters,

dmemcache.inc

@@ -149,12 +149,8 @@ function _dmemcache_set_pieces($key, $value, $exp = 0, $bin = 'cache', $mc = NUL
     $serialized = FALSE;
   }
   else {
-    if (extension_loaded('igbinary') && variable_get('memcache_enable_igbinary', TRUE)) {
-      $data = igbinary_serialize($value);
-    }
-    else {
-      $data = serialize($value);
-    }
+    $serialize_function = dmemcache_serialize();
+    $data = $serialize_function($value);
     $serialized = TRUE;
   }
 
@@ -335,12 +331,8 @@ function _dmemcache_get_pieces($item, $key, $bin = 'cache', $mc = NULL) {
     return $data;
   }
   else {
-    if (extension_loaded('igbinary') && variable_get('memcache_enable_igbinary', TRUE)) {
-      return igbinary_unserialize($data);
-    }
-    else {
-      return unserialize($data);
-    }
+    $unserialize_function = dmemcache_unserialize();
+    return $unserialize_function($value);
   }
 }
 
@@ -640,6 +632,78 @@ function dmemcache_extension() {
   return $extension;
 }
 
+/**
+ * Determine which serialize extension to use: serialize (none), igbinary,
+ * or msgpack.
+ *
+ * By default we prefer the igbinary extension, then the msgpack extension,
+ * then the core serialize functions. This can be overridden in settings.php.
+ */
+function dmemcache_serialize_extension() {
+  static $extension = NULL;
+  if ($extension === NULL) {
+    $preferred = strtolower(variable_get('memcache_serialize', NULL));
+    // Fastpath if we're forcing php's own serialize function.
+    if ($preferred == 'serialize') {
+      $extension = $preferred;
+    }
+    // Otherwise, find an available extension favoring configuration.
+    else {
+      $igbinary_available = extension_loaded('igbinary');
+      $msgpack_available = extension_loaded('msgpack');
+      if ($preferred == 'igbinary' && $igbinary_available) {
+        $extension = $preferred;
+      }
+      elseif ($preferred == 'msgpack' && $msgpack_available) {
+        $extension = $preferred;
+      }
+      else {
+        // No (valid) serialize extension specified, try igbinary.
+        if ($igbinary_available) {
+          $extension = 'igbinary';
+        }
+        // Next try msgpack.
+        else if ($msgpack_available) {
+          $extension = 'msgpack';
+        }
+        // Finally fall back to core serialize.
+        else {
+          $extension = 'serialize';
+        }
+      }
+    }
+  }
+  return $extension;
+}
+
+/**
+ * Return proper serialize function.
+ */
+function dmemcache_serialize() {
+  switch (dmemcache_serialize_extension()) {
+    case 'igbinary':
+      return 'igbinary_serialize';
+    case 'msgpack':
+      return 'msgpack_pack';
+    default:
+      return 'serialize';
+  }
+}
+
+/**
+ * Return proper unserialize function.
+ */
+function dmemcache_unserialize() {
+  switch (dmemcache_serialize_extension()) {
+    case 'igbinary':
+      return 'igbinary_unserialize';
+    case 'msgpack':
+      return 'msgpack_unpack';
+    default:
+      return 'unserialize';
+  }
+}
+
 /**
  * Return a new memcache instance.
  */

memcache_admin/memcache_admin.module

@@ -338,11 +338,9 @@ function memcache_admin_stats($bin = 'default') {
     $item = array(
       'label' => t('Serialize function')
     );
-    if (extension_loaded('igbinary') && variable_get('memcache_enable_igbinary', TRUE)) {
-      $serialize_function = t('igbinary_serialize v!version', array('!version' => phpversion('igbinary')));
-    }
-    else {
-      $serialize_function = 'serialize';
+    $serialize_function = dmemcache_serialize();
+    if ($serialize_function != 'serialize') {
+      $serialize_function = t('!function v!version', array('!function' => $serialize_function, '!version' => phpversion(dmemcache_serialize_extension())));
     }
     if (count($aggregate)) {
       $report['uptime'][] = $item;