Revision: Thu, 28 Sep 2023 12:35:38 GMT
v3.4 – outdated
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Debug - Dumping Variables

If you're using Spiral Framework 3.x, you might notice that there aren't any built-in tools for dumping variables.

However, you can use third-party packages like symfony/var-dumper for dumping variables. If you want to dump the contents of your variables to the RoadRunner error log, you can create a function like the one shown in the example below:



use Symfony\Component\VarDumper\Caster\ReflectionCaster;
use Symfony\Component\VarDumper\Cloner\VarCloner;
use Symfony\Component\VarDumper\Dumper\CliDumper;
use Symfony\Component\VarDumper\VarDumper;

if (!\function_exists('dumprr')) {
     * Dump value int STDERR.
    function dumprr(mixed $value, mixed ...$values): mixed
        $previous = $_SERVER['VAR_DUMPER_FORMAT'] ?? false;

        if (!\defined('STDERR')) {
            \define('STDERR', \fopen('php://stderr', 'wb'));
        static $dumper = new CliDumper(STDERR);

        // Output modifiers
        $cloner = new VarCloner();
        // remove File and Line definitions from a custom closure dump
        /** @psalm-suppress InvalidArgument */

        // Set new handler and store previous one
        $prevent = VarDumper::setHandler(static fn ($value) => $dumper->dump($cloner->cloneVar($value)));
        $result = VarDumper::dump($value);

        foreach ($values as $v) {

        // Reset handler

        if ($previous) {
            $_SERVER['VAR_DUMPER_FORMAT'] = $previous;

        return $result;

The spiral/app contains symfony/var-dumper package, and there's also a helpful function dumprr that you can use.