PHP 8.1 compatible

[AnnAngela]

When I tried to install Cachet with PHP 8.1, there was an error throwed and the installation had been stopped:

shell output

``` root@annangela:/var/www/Cachet# php artisan app:install PHP Fatal error: During inheritance of IteratorAggregate: Uncaught ErrorException: Return type of Symfony\Component\HttpFoundation\ParameterBag::getIterator() should either be compatible with IteratorAggregate::getIterator(): Traversable, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /var/www/Cachet/vendor/symfony/http-foundation/ParameterBag.php:224 Stack trace: #0 /var/www/Cachet/vendor/symfony/http-foundation/ParameterBag.php(19): Illuminate\Foundation\Bootstrap\HandleExceptions->handleError() #1 /var/www/Cachet/vendor/composer/ClassLoader.php(571): include('...') #2 /var/www/Cachet/vendor/composer/ClassLoader.php(428): Composer\Autoload\includeFile() #3 /var/www/Cachet/vendor/symfony/http-foundation/Request.php(240): Composer\Autoload\ClassLoader->loadClass() #4 /var/www/Cachet/vendor/symfony/http-foundation/Request.php(222): Symfony\Component\HttpFoundation\Request->initialize() #5 /var/www/Cachet/vendor/symfony/http-foundation/Request.php(1913): Symfony\Component\HttpFoundation\Request->__construct() #6 /var/www/Cachet/vendor/symfony/http-foundation/Request.php(398): Symfony\Component\HttpFoundation\Request::createRequestFromFactory() #7 /var/www/Cachet/vendor/laravel/framework/src/Illuminate/Foundation/Bootstrap/SetRequestForConsole.php(20): Symfony\Component\HttpFoundation\Request::create() #8 /var/www/Cachet/vendor/laravel/framework/src/Illuminate/Foundation/Application.php(203): Illuminate\Foundation\Bootstrap\SetRequestForConsole->bootstrap() #9 /var/www/Cachet/vendor/laravel/framework/src/Illuminate/Foundation/Console/Kernel.php(219): Illuminate\Foundation\Application->bootstrapWith() #10 /var/www/Cachet/vendor/laravel/framework/src/Illuminate/Foundation/Console/Kernel.php(105): Illuminate\Foundation\Console\Kernel->bootstrap() #11 /var/www/Cachet/artisan(35): Illuminate\Foundation\Console\Kernel->handle() #12 {main} in /var/www/Cachet/vendor/symfony/http-foundation/ParameterBag.php on line 19 PHP Fatal error: Uncaught ErrorException: Method ReflectionParameter::getClass() is deprecated in /var/www/Cachet/vendor/laravel/framework/src/Illuminate/Container/Container.php:794 Stack trace: #0 /var/www/Cachet/vendor/laravel/framework/src/Illuminate/Container/Container.php(794): Illuminate\Foundation\Bootstrap\HandleExceptions->handleError() #1 /var/www/Cachet/vendor/laravel/framework/src/Illuminate/Container/Container.php(774): Illuminate\Container\Container->getDependencies() #2 /var/www/Cachet/vendor/laravel/framework/src/Illuminate/Container/Container.php(629): Illuminate\Container\Container->build() #3 /var/www/Cachet/vendor/laravel/framework/src/Illuminate/Foundation/Application.php(697): Illuminate\Container\Container->make() #4 /var/www/Cachet/vendor/laravel/framework/src/Illuminate/Container/Container.php(230): Illuminate\Foundation\Application->make() #5 /var/www/Cachet/vendor/laravel/framework/src/Illuminate/Container/Container.php(731): Illuminate\Container\Container->Illuminate\Container\{closure}() #6 /var/www/Cachet/vendor/laravel/framework/src/Illuminate/Container/Container.php(629): Illuminate\Container\Container->build() #7 /var/www/Cachet/vendor/laravel/framework/src/Illuminate/Foundation/Application.php(697): Illuminate\Container\Container->make() #8 /var/www/Cachet/vendor/laravel/framework/src/Illuminate/Foundation/Bootstrap/HandleExceptions.php(154): Illuminate\Foundation\Application->make() #9 /var/www/Cachet/vendor/laravel/framework/src/Illuminate/Foundation/Bootstrap/HandleExceptions.php(79): Illuminate\Foundation\Bootstrap\HandleExceptions->getExceptionHandler() #10 /var/www/Cachet/vendor/laravel/framework/src/Illuminate/Foundation/Bootstrap/HandleExceptions.php(118): Illuminate\Foundation\Bootstrap\HandleExceptions->handleException() #11 [internal function]: Illuminate\Foundation\Bootstrap\HandleExceptions->handleShutdown() #12 {main} thrown in /var/www/Cachet/vendor/laravel/framework/src/Illuminate/Container/Container.php on line 794 ```

And after googling the keyword ReturnTypeWillChange of the output, I found out an issue from phpmyadmin/phpmyadmin#16746 and I believed the problem is the incompatible between Cachet and PHP 8.1. Please help to fix it!

Reference: The Backward Incompatible Changes Chapter in PHP 8.1 migration guide

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[williamdes]

Hi @AnnAngela I think this can be fixed by updating the composer.lock file of this repo or bumping a version in https://github.com/CachetHQ/Cachet/blob/2.4/composer.json

[jbrooksuk]

Thank you for your input on Cachet 2.x. We are shifting our attention and resources to Cachet 3.x and will no longer be supporting the 2.x version. If your feedback or issue is relevant to the 3.x series, we encourage you to engage with the new branch.

For more information on the Cachet rebuild and our plans for 3.x, you can read the announcement here.

We appreciate your understanding and look forward to your contributions to the new version.