<?php
namespace React\Dns\Query;
use React\Promise\CancellablePromiseInterface;
use React\Promise\Deferred;
class RetryExecutor implements ExecutorInterface
{
private $executor;
private $retries;
public function __construct(ExecutorInterface $executor, $retries = 2)
{
$this->executor = $executor;
$this->retries = $retries;
}
public function query($nameserver, Query $query)
{
return $this->tryQuery($nameserver, $query, $this->retries);
}
public function tryQuery($nameserver, Query $query, $retries)
{
$deferred = new Deferred(function () use (&$promise) {
if ($promise instanceof CancellablePromiseInterface) {
$promise->cancel();
}
});
$success = function ($value) use ($deferred, &$errorback) {
$errorback = null;
$deferred->resolve($value);
};
$executor = $this->executor;
$errorback = function ($e) use ($deferred, &$promise, $nameserver, $query, $success, &$errorback, &$retries, $executor) {
if (!$e instanceof TimeoutException) {
$errorback = null;
$deferred->reject($e);
} elseif ($retries <= 0) {
$errorback = null;
$deferred->reject($e = new \RuntimeException(
'DNS query for ' . $query->name . ' failed: too many retries',
0,
$e
));
// avoid garbage references by replacing all closures in call stack.
// what a lovely piece of code!
$r = new \ReflectionProperty('Exception', 'trace');
$r->setAccessible(true);
$trace = $r->getValue($e);
foreach ($trace as &$one) {
foreach ($one['args'] as &$arg) {
if ($arg instanceof \Closure) {
$arg = 'Object(' . \get_class($arg) . ')';
}
}
}
$r->setValue($e, $trace);
} else {
--$retries;
$promise = $executor->query($nameserver, $query)->then(
$success,
$errorback
);
}
};
$promise = $this->executor->query($nameserver, $query)->then(
$success,
$errorback
);
return $deferred->promise();
}
}