Thrift PHP generation Redux

Summary: Chopping the amount of code generated by Thrift for PHP services by two orders of magnitude (approx 25% of the previous size). This is done via putting more logic in a dynamic base class and taking it out of the generated code. Hopefully this wins back the CPU cycles paid just to load code from APC at the cost of a marginal increase in dynamic execution runtime.

Reviewed By: sgrimm, dreiss

Test Plan: Ran all the tests in trunk/test/php, also tested the API generate code and Falcon, etc. in my sandbox


git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@665328 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/lib/php/src/Thrift.php b/lib/php/src/Thrift.php
index 21a175c..9c7b4e6 100644
--- a/lib/php/src/Thrift.php
+++ b/lib/php/src/Thrift.php
@@ -43,14 +43,711 @@
   const EXCEPTION = 3;
 }
 
+/**
+ * NOTE(mcslee): This currently contains a ton of duplicated code from TBase
+ * because we need to save CPU cycles and this is not yet in an extension.
+ * Ideally we'd multiply-inherit TException from both Exception and Base, but
+ * that's not possible in PHP and there are no modules either, so for now we
+ * apologetically take a trip to HackTown.
+ *
+ * Can be called with standard Exception constructor (message, code) or with
+ * Thrift Base object constructor (spec, vals).
+ *
+ * @param mixed $p1 Message (string) or type-spec (array)
+ * @param mixed $p2 Code (integer) or values (array)
+ */
 class TException extends Exception {
-  function __construct($message=null, $code=0) {
-    parent::__construct($message, $code);
+  function __construct($p1=null, $p2=0) {
+    if (is_array($p1) && is_array($p2)) {
+      $spec = $p1;
+      $vals = $p2;
+      foreach ($spec as $fid => $fspec) {
+        $var = $fspec['var'];
+        if (isset($vals[$var])) {
+          $this->$var = $vals[$var];
+        }
+      }
+    } else {
+      parent::__construct($p1, $p2);
+    }
+  }
+
+  static $tmethod = array(TType::BOOL   => 'Bool',
+                          TType::BYTE   => 'Byte',
+                          TType::I16    => 'I16',
+                          TType::I32    => 'I32',
+                          TType::I64    => 'I64',
+                          TType::DOUBLE => 'Double',
+                          TType::STRING => 'String');
+
+  private function _readMap(&$var, $spec, $input) {
+    $xfer = 0;
+    $ktype = $spec['ktype'];
+    $vtype = $spec['vtype'];
+    $kread = $vread = null;
+    if (isset(TBase::$tmethod[$ktype])) {
+      $kread = 'read'.TBase::$tmethod[$ktype];
+    } else {
+      $kspec = $spec['key'];
+    }
+    if (isset(TBase::$tmethod[$vtype])) {
+      $vread = 'read'.TBase::$tmethod[$vtype];
+    } else {
+      $vspec = $spec['val'];
+    }
+    $var = array();
+    $_ktype = $_vtype = $size = 0;
+    $xfer += $input->readMapBegin($_ktype, $_vtype, $size);
+    for ($i = 0; $i < $size; ++$i) {
+      $key = $val = null;
+      if ($kread !== null) {
+        $xfer += $input->$kread($key);
+      } else {
+        switch ($ktype) {
+        case TType::STRUCT:
+          $class = $kspec['class'];
+          $key = new $class();
+          $xfer += $key->read($input);
+          break;
+        case TType::MAP:
+          $xfer += $this->_readMap($key, $kspec, $input);
+          break;
+        case TType::LST:
+          $xfer += $this->_readList($key, $kspec, $input, false);
+          break;
+        case TType::SET:
+          $xfer += $this->_readList($key, $kspec, $input, true);
+          break;
+        }
+      }
+      if ($vread !== null) {
+        $xfer += $input->$vread($val);
+      } else {
+        switch ($vtype) {
+        case TType::STRUCT:
+          $class = $vspec['class'];
+          $val = new $class();
+          $xfer += $val->read($input);
+          break;
+        case TType::MAP:
+          $xfer += $this->_readMap($val, $vspec, $input);
+          break;
+        case TType::LST:
+          $xfer += $this->_readList($val, $vspec, $input, false);
+          break;
+        case TType::SET:
+          $xfer += $this->_readList($val, $vspec, $input, true);
+          break;
+        }
+      }
+      $var[$key] = $val;
+    }
+    $xfer += $input->readMapEnd();
+    return $xfer;
+  }
+
+  private function _readList(&$var, $spec, $input, $set=false) {
+    $xfer = 0;
+    $etype = $spec['etype'];
+    $eread = $vread = null;
+    if (isset(TBase::$tmethod[$etype])) {
+      $eread = 'read'.TBase::$tmethod[$etype];
+    } else {
+      $espec = $spec['elem'];
+    }
+    $var = array();
+    $_etype = $size = 0;
+    if ($set) {
+      $xfer += $input->readSetBegin($_etype, $size);
+    } else {
+      $xfer += $input->readListBegin($_etype, $size);
+    }
+    for ($i = 0; $i < $size; ++$i) {
+      $elem = null;
+      if ($eread !== null) {
+        $xfer += $input->$eread($elem);
+      } else {
+        $espec = $spec['elem'];
+        switch ($etype) {
+        case TType::STRUCT:
+          $class = $espec['class'];
+          $elem = new $class();
+          $xfer += $elem->read($input);
+          break;
+        case TType::MAP:
+          $xfer += $this->_readMap($key, $espec, $input);
+          break;
+        case TType::LST:
+          $xfer += $this->_readList($key, $espec, $input, false);
+          break;
+        case TType::SET:
+          $xfer += $this->_readList($key, $espec, $input, true);
+          break;
+        }
+      }
+      if ($set) {
+        $var[$elem] = true;
+      } else {
+        $var []= $elem;
+      }
+    }
+    if ($set) {
+      $xfer += $input->readSetEnd();
+    } else {
+      $xfer += $input->readListEnd();
+    }
+    return $xfer;
+  }
+
+  protected function _read($class, $spec, $input) {
+    $xfer = 0;
+    $fname = null;
+    $ftype = 0;
+    $fid = 0;
+    $xfer += $input->readStructBegin($fname);
+    $fast_binary = (bool)
+      is_a($input, 'TBinaryProtocolAccelerated') &&
+      function_exists('thrift_protocol_binary_deserialize');
+
+    while (true) {
+      $xfer += $input->readFieldBegin($fname, $ftype, $fid);
+      if ($ftype == TType::STOP) {
+        break;
+      }
+      if (isset($spec[$fid])) {
+        $fspec = $spec[$fid];
+        $var = $fspec['var'];
+        if ($ftype == $fspec['type']) {
+          $xfer = 0;
+          if ($fast_binary) {
+            $class = isset($fspec['class']) ? $fspec['class'] : null;
+            $this->$var = thrift_protocol_binary_deserialize($ftype, $input, $class);
+          } else {
+            if (isset(TBase::$tmethod[$ftype])) {
+              $func = 'read'.TBase::$tmethod[$ftype];
+              $xter += $input->$func($this->$var);
+            } else {
+              switch ($ftype) {
+              case TType::STRUCT:
+                $class = $fspec['class'];
+                $this->$var = new $class();
+                $xfer += $this->$var->read($input);
+                break;
+              case TType::MAP:
+                $xfer += $this->_readMap($this->$var, $fspec, $input);
+                break;
+              case TType::LST:
+                $xfer += $this->_readList($this->$var, $fspec, $input, false);
+                break;
+              case TType::SET:
+                $xfer += $this->_readList($this->$var, $fspec, $input, true);
+                break;
+              }
+            }
+          }
+        } else {
+          $xfer += $input->skip($ftype);
+        }
+      } else {
+        $xfer += $input->skip($ftype);
+      }
+      $xfer += $input->readFieldEnd();
+    }
+    $xfer += $input->readStructEnd();
+    return $xfer;
+  }
+
+  private function _writeMap($var, $spec, $output) {
+    $xfer = 0;
+    $ktype = $spec['ktype'];
+    $vtype = $spec['vtype'];
+    $kwrite = $vwrite = null;
+    if (isset(TBase::$tmethod[$ktype])) {
+      $kwrite = 'write'.TBase::$tmethod[$ktype];
+    } else {
+      $kspec = $spec['key'];
+    }
+    if (isset(TBase::$tmethod[$vtype])) {
+      $vwrite = 'write'.TBase::$tmethod[$vtype];
+    } else {
+      $vspec = $spec['val'];
+    }
+    $xfer += $output->writeMapBegin($ktype, $vtype, count($var));
+    foreach ($var as $key => $val) {
+      if (isset($kwrite)) {
+        $xfer += $output->$kwrite($key);
+      } else {
+        switch ($ktype) {
+        case TType::STRUCT:
+          $xfer += $key->write($output);
+          break;
+        case TType::MAP:
+          $xfer += $this->_writeMap($key, $kspec, $output);
+          break;
+        case TType::LST:
+          $xfer += $this->_writeList($key, $kspec, $output, false);
+          break;
+        case TType::SET:
+          $xfer += $this->_writeList($key, $kspec, $output, true);
+          break;
+        }
+      }
+      if (isset($vwrite)) {
+        $xfer += $output->$vwrite($val);
+      } else {
+        switch ($vtype) {
+        case TType::STRUCT:
+          $xfer += $val->write($output);
+          break;
+        case TType::MAP:
+          $xfer += $this->_writeMap($val, $vspec, $output);
+          break;
+        case TType::LST:
+          $xfer += $this->_writeList($val, $vspec, $output, false);
+          break;
+        case TType::SET:
+          $xfer += $this->_writeList($val, $vspec, $output, true);
+          break;
+        }
+      }
+    }
+    $xfer += $output->writeMapEnd();
+    return $xfer;
+  }
+
+  private function _writeList($var, $spec, $output, $set=false) {
+    $xfer = 0;
+    $etype = $spec['etype'];
+    $ewrite = null;
+    if (isset(TBase::$tmethod[$etype])) {
+      $ewrite = 'write'.TBase::$tmethod[$etype];
+    } else {
+      $espec = $spec['elem'];
+    }
+    if ($set) {
+      $xfer += $output->writeSetBegin($etype, count($var));
+    } else {
+      $xfer += $output->writeListBegin($etype, count($var));
+    }
+    foreach ($var as $key => $val) {
+      $elem = $set ? $key : $val;
+      if (isset($ewrite)) {
+        $xfer += $output->$ewrite($elem);
+      } else {
+        switch ($etype) {
+        case TType::STRUCT:
+          $xfer += $elem->write($output);
+          break;
+        case TType::MAP:
+          $xfer += $this->_writeMap($elem, $espec, $output);
+          break;
+        case TType::LST:
+          $xfer += $this->_writeList($elem, $espec, $output, false);
+          break;
+        case TType::SET:
+          $xfer += $this->_writeList($elem, $espec, $output, true);
+          break;
+        }
+      }
+    }
+    if ($set) {
+      $xfer += $output->writeSetEnd();
+    } else {
+      $xfer += $output->writeListEnd();
+    }
+    return $xfer;
+  }
+
+  protected function _write($class, $spec, $output) {
+    $xfer = 0;
+    $xfer += $output->writeStructBegin($class);
+    foreach ($spec as $fid => $fspec) {
+      $var = $fspec['var'];
+      if ($this->$var !== null) {
+        $ftype = $fspec['type'];
+        $xfer += $output->writeFieldBegin($var, $ftype, $fid);
+        if (isset(TBase::$tmethod[$ftype])) {
+          $func = 'write'.TBase::$tmethod[$ftype];
+          $xter += $output->$func($this->$var);
+        } else {
+          switch ($ftype) {
+          case TType::STRUCT:
+            $xfer += $this->$var->write($output);
+            break;
+          case TType::MAP:
+            $xfer += $this->_writeMap($this->$var, $fspec, $output);
+            break;
+          case TType::LST:
+            $xfer += $this->_writeList($this->$var, $fspec, $output, false);
+            break;
+          case TType::SET:
+            $xfer += $this->_writeList($this->$var, $fspec, $output, true);
+            break;
+          }
+        }
+        $xfer += $output->writeFieldEnd();
+      }
+    }
+    $xfer += $output->writeFieldStop();
+    $xfer += $output->writeStructEnd();
+    return $xfer;
+  }
+
+}
+
+/**
+ * Base class from which other Thrift structs extend. This is so that we can
+ * cut back on the size of the generated code which is turning out to have a
+ * nontrivial cost just to load thanks to the wondrously abysmal implementation
+ * of PHP. Note that code is intentionally duplicated in here to avoid making
+ * function calls for every field or member of a container..
+ */
+abstract class TBase {
+
+  static $tmethod = array(TType::BOOL   => 'Bool',
+                          TType::BYTE   => 'Byte',
+                          TType::I16    => 'I16',
+                          TType::I32    => 'I32',
+                          TType::I64    => 'I64',
+                          TType::DOUBLE => 'Double',
+                          TType::STRING => 'String');
+
+  abstract function read($input);
+
+  abstract function write($output);
+
+  public function __construct($spec=null, $vals=null) {
+    if (is_array($spec) && is_array($vals)) {
+      foreach ($spec as $fid => $fspec) {
+        $var = $fspec['var'];
+        if (isset($vals[$var])) {
+          $this->$var = $vals[$var];
+        }
+      }
+    }
+  }
+
+  private function _readMap(&$var, $spec, $input) {
+    $xfer = 0;
+    $ktype = $spec['ktype'];
+    $vtype = $spec['vtype'];
+    $kread = $vread = null;
+    if (isset(TBase::$tmethod[$ktype])) {
+      $kread = 'read'.TBase::$tmethod[$ktype];
+    } else {
+      $kspec = $spec['key'];
+    }
+    if (isset(TBase::$tmethod[$vtype])) {
+      $vread = 'read'.TBase::$tmethod[$vtype];
+    } else {
+      $vspec = $spec['val'];
+    }
+    $var = array();
+    $_ktype = $_vtype = $size = 0;
+    $xfer += $input->readMapBegin($_ktype, $_vtype, $size);
+    for ($i = 0; $i < $size; ++$i) {
+      $key = $val = null;
+      if ($kread !== null) {
+        $xfer += $input->$kread($key);
+      } else {
+        switch ($ktype) {
+        case TType::STRUCT:
+          $class = $kspec['class'];
+          $key = new $class();
+          $xfer += $key->read($input);
+          break;
+        case TType::MAP:
+          $xfer += $this->_readMap($key, $kspec, $input);
+          break;
+        case TType::LST:
+          $xfer += $this->_readList($key, $kspec, $input, false);
+          break;
+        case TType::SET:
+          $xfer += $this->_readList($key, $kspec, $input, true);
+          break;
+        }
+      }
+      if ($vread !== null) {
+        $xfer += $input->$vread($val);
+      } else {
+        switch ($vtype) {
+        case TType::STRUCT:
+          $class = $vspec['class'];
+          $val = new $class();
+          $xfer += $val->read($input);
+          break;
+        case TType::MAP:
+          $xfer += $this->_readMap($val, $vspec, $input);
+          break;
+        case TType::LST:
+          $xfer += $this->_readList($val, $vspec, $input, false);
+          break;
+        case TType::SET:
+          $xfer += $this->_readList($val, $vspec, $input, true);
+          break;
+        }
+      }
+      $var[$key] = $val;
+    }
+    $xfer += $input->readMapEnd();
+    return $xfer;
+  }
+
+  private function _readList(&$var, $spec, $input, $set=false) {
+    $xfer = 0;
+    $etype = $spec['etype'];
+    $eread = $vread = null;
+    if (isset(TBase::$tmethod[$etype])) {
+      $eread = 'read'.TBase::$tmethod[$etype];
+    } else {
+      $espec = $spec['elem'];
+    }
+    $var = array();
+    $_etype = $size = 0;
+    if ($set) {
+      $xfer += $input->readSetBegin($_etype, $size);
+    } else {
+      $xfer += $input->readListBegin($_etype, $size);
+    }
+    for ($i = 0; $i < $size; ++$i) {
+      $elem = null;
+      if ($eread !== null) {
+        $xfer += $input->$eread($elem);
+      } else {
+        $espec = $spec['elem'];
+        switch ($etype) {
+        case TType::STRUCT:
+          $class = $espec['class'];
+          $elem = new $class();
+          $xfer += $elem->read($input);
+          break;
+        case TType::MAP:
+          $xfer += $this->_readMap($key, $espec, $input);
+          break;
+        case TType::LST:
+          $xfer += $this->_readList($key, $espec, $input, false);
+          break;
+        case TType::SET:
+          $xfer += $this->_readList($key, $espec, $input, true);
+          break;
+        }
+      }
+      if ($set) {
+        $var[$elem] = true;
+      } else {
+        $var []= $elem;
+      }
+    }
+    if ($set) {
+      $xfer += $input->readSetEnd();
+    } else {
+      $xfer += $input->readListEnd();
+    }
+    return $xfer;
+  }
+
+  protected function _read($class, $spec, $input) {
+    $xfer = 0;
+    $fname = null;
+    $ftype = 0;
+    $fid = 0;
+    $xfer += $input->readStructBegin($fname);
+    $fast_binary = (bool)
+      is_a($input, 'TBinaryProtocolAccelerated') &&
+      function_exists('thrift_protocol_binary_deserialize');
+
+    while (true) {
+      $xfer += $input->readFieldBegin($fname, $ftype, $fid);
+      if ($ftype == TType::STOP) {
+        break;
+      }
+      if (isset($spec[$fid])) {
+        $fspec = $spec[$fid];
+        $var = $fspec['var'];
+        if ($ftype == $fspec['type']) {
+          $xfer = 0;
+          if ($fast_binary) {
+            $class = isset($fspec['class']) ? $fspec['class'] : null;
+            $this->$var = thrift_protocol_binary_deserialize($ftype, $input, $class);
+          } else {
+            if (isset(TBase::$tmethod[$ftype])) {
+              $func = 'read'.TBase::$tmethod[$ftype];
+              $xter += $input->$func($this->$var);
+            } else {
+              switch ($ftype) {
+              case TType::STRUCT:
+                $class = $fspec['class'];
+                $this->$var = new $class();
+                $xfer += $this->$var->read($input);
+                break;
+              case TType::MAP:
+                $xfer += $this->_readMap($this->$var, $fspec, $input);
+                break;
+              case TType::LST:
+                $xfer += $this->_readList($this->$var, $fspec, $input, false);
+                break;
+              case TType::SET:
+                $xfer += $this->_readList($this->$var, $fspec, $input, true);
+                break;
+              }
+            }
+          }
+        } else {
+          $xfer += $input->skip($ftype);
+        }
+      } else {
+        $xfer += $input->skip($ftype);
+      }
+      $xfer += $input->readFieldEnd();
+    }
+    $xfer += $input->readStructEnd();
+    return $xfer;
+  }
+
+  private function _writeMap($var, $spec, $output) {
+    $xfer = 0;
+    $ktype = $spec['ktype'];
+    $vtype = $spec['vtype'];
+    $kwrite = $vwrite = null;
+    if (isset(TBase::$tmethod[$ktype])) {
+      $kwrite = 'write'.TBase::$tmethod[$ktype];
+    } else {
+      $kspec = $spec['key'];
+    }
+    if (isset(TBase::$tmethod[$vtype])) {
+      $vwrite = 'write'.TBase::$tmethod[$vtype];
+    } else {
+      $vspec = $spec['val'];
+    }
+    $xfer += $output->writeMapBegin($ktype, $vtype, count($var));
+    foreach ($var as $key => $val) {
+      if (isset($kwrite)) {
+        $xfer += $output->$kwrite($key);
+      } else {
+        switch ($ktype) {
+        case TType::STRUCT:
+          $xfer += $key->write($output);
+          break;
+        case TType::MAP:
+          $xfer += $this->_writeMap($key, $kspec, $output);
+          break;
+        case TType::LST:
+          $xfer += $this->_writeList($key, $kspec, $output, false);
+          break;
+        case TType::SET:
+          $xfer += $this->_writeList($key, $kspec, $output, true);
+          break;
+        }
+      }
+      if (isset($vwrite)) {
+        $xfer += $output->$vwrite($val);
+      } else {
+        switch ($vtype) {
+        case TType::STRUCT:
+          $xfer += $val->write($output);
+          break;
+        case TType::MAP:
+          $xfer += $this->_writeMap($val, $vspec, $output);
+          break;
+        case TType::LST:
+          $xfer += $this->_writeList($val, $vspec, $output, false);
+          break;
+        case TType::SET:
+          $xfer += $this->_writeList($val, $vspec, $output, true);
+          break;
+        }
+      }
+    }
+    $xfer += $output->writeMapEnd();
+    return $xfer;
+  }
+
+  private function _writeList($var, $spec, $output, $set=false) {
+    $xfer = 0;
+    $etype = $spec['etype'];
+    $ewrite = null;
+    if (isset(TBase::$tmethod[$etype])) {
+      $ewrite = 'write'.TBase::$tmethod[$etype];
+    } else {
+      $espec = $spec['elem'];
+    }
+    if ($set) {
+      $xfer += $output->writeSetBegin($etype, count($var));
+    } else {
+      $xfer += $output->writeListBegin($etype, count($var));
+    }
+    foreach ($var as $key => $val) {
+      $elem = $set ? $key : $val;
+      if (isset($ewrite)) {
+        $xfer += $output->$ewrite($elem);
+      } else {
+        switch ($etype) {
+        case TType::STRUCT:
+          $xfer += $elem->write($output);
+          break;
+        case TType::MAP:
+          $xfer += $this->_writeMap($elem, $espec, $output);
+          break;
+        case TType::LST:
+          $xfer += $this->_writeList($elem, $espec, $output, false);
+          break;
+        case TType::SET:
+          $xfer += $this->_writeList($elem, $espec, $output, true);
+          break;
+        }
+      }
+    }
+    if ($set) {
+      $xfer += $output->writeSetEnd();
+    } else {
+      $xfer += $output->writeListEnd();
+    }
+    return $xfer;
+  }
+
+  protected function _write($class, $spec, $output) {
+    $xfer = 0;
+    $xfer += $output->writeStructBegin($class);
+    foreach ($spec as $fid => $fspec) {
+      $var = $fspec['var'];
+      if ($this->$var !== null) {
+        $ftype = $fspec['type'];
+        $xfer += $output->writeFieldBegin($var, $ftype, $fid);
+        if (isset(TBase::$tmethod[$ftype])) {
+          $func = 'write'.TBase::$tmethod[$ftype];
+          $xter += $output->$func($this->$var);
+        } else {
+          switch ($ftype) {
+          case TType::STRUCT:
+            $xfer += $this->$var->write($output);
+            break;
+          case TType::MAP:
+            $xfer += $this->_writeMap($this->$var, $fspec, $output);
+            break;
+          case TType::LST:
+            $xfer += $this->_writeList($this->$var, $fspec, $output, false);
+            break;
+          case TType::SET:
+            $xfer += $this->_writeList($this->$var, $fspec, $output, true);
+            break;
+          }
+        }
+        $xfer += $output->writeFieldEnd();
+      }
+    }
+    $xfer += $output->writeFieldStop();
+    $xfer += $output->writeStructEnd();
+    return $xfer;
   }
 }
 
 class TApplicationException extends TException {
-  
+  static $_TSPEC =
+    array(1 => array('var' => 'message',
+                     'type' => TType::STRING),
+          2 => array('var' => 'code',
+                     'type' => TType::I32));
+
   const UNKNOWN = 0;
   const UNKNOWN_METHOD = 1;
   const INVALID_MESSAGE_TYPE = 2;
@@ -62,55 +759,21 @@
     parent::__construct($message, $code);
   }
 
-  public function read($input) {
-    $xfer = 0;
-    $fname = null;
-    $ftype = 0;
-    $fid = 0;
-    $xfer += $input->readStructBegin($fname);
-    while (true)
-    {
-      $xfer += $input->readFieldBegin($fname, $ftype, $fid);
-      if ($ftype == TType::STOP) {
-        break;
-      }
-      switch ($fid)
-      {
-        case 1:
-          if ($ftype == TType::STRING) {
-            $xfer += $input->readString($this->message);
-          } else {
-            $xfer += $input->skip($ftype);
-          }
-          break;
-        case 2:
-          if ($ftype == TType::I32) {
-            $xfer += $input->readI32($this->code);
-          } else {
-            $xfer += $input->skip($ftype);
-          }
-          break;
-        default:
-          $xfer += $input->skip($ftype);
-          break;
-      }
-      $xfer += $input->readFieldEnd();
-    }
-    $xfer += $input->readStructEnd();
-    return $xfer;
+  public function read($output) {
+    return $this->_read('TApplicationException', self::$_TSPEC, $output);
   }
 
   public function write($output) {
     $xfer = 0;
     $xfer += $output->writeStructBegin('TApplicationException');
-    if ($this->getMessage()) {
+    if ($message = $this->getMessage()) {
       $xfer += $output->writeFieldBegin('message', TType::STRING, 1);
-      $xfer += $output->writeString($this->getMessage());
+      $xfer += $output->writeString($message);
       $xfer += $output->writeFieldEnd();
     }
-    if ($this->getCode()) {
+    if ($code = $this->getCode()) {
       $xfer += $output->writeFieldBegin('type', TType::I32, 2);
-      $xfer += $output->writeI32($this->getCode());
+      $xfer += $output->writeI32($code);
       $xfer += $output->writeFieldEnd();
     }
     $xfer += $output->writeFieldStop();