/**
* 执行map reduce操作,为了防止数据量过大，导致无法完成mapreduce,统一采用集合的方式，取代内存方式
* 内存方式，不允许执行过程的数据量量超过物理内存的10%，故无法进行大数量分析工作。
*
* @param array $command
*/
public function mapReduce($out = null, $map, $reduce, $query = array(), $finalize = null, $method = 'replace', $scope = null, $sort = array('$natural' => 1), $limit = null)
{
if ($out == null) {
$out = md5(serialize(func_get_args()));
}
try {
// map reduce执行锁管理开始
$locks = new self($this->_configInstance, 'locks', DB_MAPREDUCE, $this->_cluster);
$locks->setReadPreference(\MongoClient::RP_PRIMARY_PREFERRED);
$checkLock = function ($out) use($locks) {
$check = $locks->findOne(array('out' => $out));
if ($check == null) {
$locks->insert(array('out' => $out, 'isRunning' => true, 'expire' => new \MongoDate(time() + 300)));
return false;
} else {
if (isset($check['isRunning']) && $check['isRunning']) {
return true;
}
if ($check['isRunning'] && isset($check['expire']) && $check['expire'] instanceof \MongoDate) {
if ($check['expire']->sec > time()) {
return true;
} else {
$releaseLock($out);
return false;
}
}
$locks->update(array('out' => $out), array('$set' => array('isRunning' => true, 'expire' => new \MongoDate(time() + 300))));
return false;
}
};
$releaseLock = function ($out, $rst = null) use($locks) {
return $locks->update(array('out' => $out), array('$set' => array('isRunning' => false, 'rst' => is_string($rst) ? $rst : Json::encode($rst))));
};
$failure = function ($code, $msg) {
if (is_array($msg)) {
$msg = Json::encode($msg);
}
return array('ok' => 0, 'code' => $code, 'msg' => $msg);
};
// map reduce执行锁管理结束
if (!$checkLock($out)) {
$command = array();
$command['mapreduce'] = $this->_collection;
$command['map'] = $map instanceof \MongoCode ? $map : new \MongoCode($map);
$command['reduce'] = $reduce instanceof \MongoCode ? $reduce : new \MongoCode($reduce);
$command['query'] = $this->appendQuery($query);
if (!empty($finalize)) {
$command['finalize'] = $finalize instanceof \MongoCode ? $finalize : new \MongoCode($finalize);
}
if (!empty($sort)) {
$command['sort'] = $sort;
}
if (!empty($limit)) {
$command['limit'] = $limit;
}
if (!empty($scope)) {
$command['scope'] = $scope;
}
$command['verbose'] = true;
if (!in_array($method, array('replace', 'merge', 'reduce'), true)) {
$method = 'replace';
}
$command['out'] = array($method => $out, 'db' => DB_MAPREDUCE, 'sharded' => false, 'nonAtomic' => in_array($method, array('merge', 'reduce'), true) ? true : false);
$rst = $this->command($command);
$releaseLock($out, $rst);
if ($rst['ok'] == 1) {
if ($rst['counts']['emit'] > 0 && $rst['counts']['output'] > 0) {
$outMongoCollection = new self($this->_configInstance, $out, DB_MAPREDUCE, $this->_cluster);
$outMongoCollection->setNoAppendQuery(true);
return $outMongoCollection;
}
return $failure(500, $rst['counts']);
} else {
return $failure(501, $rst);
}
} else {
return $failure(502, '程序正在执行中，请勿频繁尝试');
}
} catch (\Exception $e) {
if (isset($releaseLock) && isset($failure)) {
$releaseLock($out, exceptionMsg($e));
return $failure(503, exceptionMsg($e));
}
var_dump(exceptionMsg($e));
}
}
