README

Application bootstrap with PSR-15 middleware pipeline.

A lightweight, PSR-compliant application kernel that wires together your container, router, middleware, and HTTP layer with zero configuration overhead.

Features

• PSR-15 middleware pipeline
• PSR-11 container integration
• Service providers for dependency registration
• Flexible route handlers (controllers, invokables, callables)
• Zero framework lock-in — uses only PSR interfaces

Installation

composer require solophp/application

Requirements

• PHP 8.2+
• PSR-7 implementation (e.g., nyholm/psr7)
• PSR-11 compatible container with set() method

Dependencies

The package depends only on PSR interfaces and solophp/contracts:

Usage

// public/index.php
<?php

require __DIR__ . '/../vendor/autoload.php';

use Solo\Application\Application;
use Solo\Application\Config;
use Solo\Dotenv\Dotenv;

$basePath = dirname(__DIR__);

Dotenv::load($basePath, ['.env', '.env.local']);

$config = new Config(
    basePath: $basePath,
    routesPath: $basePath . '/app/routes.php',
    providers: require $basePath . '/app/providers.php',
    middleware: require $basePath . '/app/middleware.php',
);

$app = new Application($config);
$app->run();

Required Services

Your application must register these services via providers:

Example provider:

<?php

namespace App\Providers;

use Nyholm\Psr7\Factory\Psr17Factory;
use Nyholm\Psr7Server\ServerRequestCreator;
use Psr\Container\ContainerInterface;
use Psr\Http\Message\ResponseFactoryInterface;
use Psr\Http\Message\ServerRequestInterface;
use Solo\Container\Container;
use Solo\Contracts\Http\EmitterInterface;
use Solo\Contracts\Router\RouterInterface;
use Solo\HttpEmitter\Emitter;
use Solo\Router\RouteCollector;

final class HttpServiceProvider
{
    public function register(Container $container): void
    {
        $container->set(Psr17Factory::class, fn() => new Psr17Factory());

        $container->set(ResponseFactoryInterface::class,
            fn(ContainerInterface $c) => $c->get(Psr17Factory::class)
        );

        $container->set(ServerRequestInterface::class, function (ContainerInterface $c) {
            $factory = $c->get(Psr17Factory::class);
            return (new ServerRequestCreator($factory, $factory, $factory, $factory))
                ->fromGlobals();
        });

        $container->set(RouterInterface::class, fn() => new RouteCollector());
        $container->set(EmitterInterface::class, fn() => new Emitter());
    }
}

Custom Container

You can provide your own container:

$container = new MyContainer();
// ... configure container ...

$app = new Application($config, $container);

The container must implement Solo\Contracts\Container\WritableContainerInterface.

Components

Request Flow

HTTP Request
      │
      ▼
Application.run()
      │
      ▼
MiddlewarePipeline
      │
      ▼
[Middleware 1] → [Middleware 2] → ... → [RoutingMiddleware]
      │
      ▼
RouteDispatcher → Controller
      │
      ▼
HTTP Response

Configuration

providers.php

<?php

return [
    HttpServiceProvider::class,
    DatabaseServiceProvider::class,
    LoggingServiceProvider::class,
];

middleware.php

<?php

return [
    CorsMiddleware::class,
    ErrorHandlerMiddleware::class,
    JsonParserMiddleware::class,
    RoutingMiddleware::class,
];

routes.php

<?php

use Solo\Contracts\Router\RouterInterface;

return function (RouterInterface $r) {
    $r->addRoute('GET', '/api/users', [UserController::class, 'index']);
    $r->addRoute('POST', '/api/users', [UserController::class, 'store']);
};

Service Providers

Service providers register dependencies in the container:

<?php

namespace App\Providers;

use Solo\Container\Container;

final class DatabaseServiceProvider
{
    public function register(Container $container): void
    {
        $container->set(Connection::class, function () {
            return new Connection(/* ... */);
        });
    }
}

License

The MIT License (MIT). Please see License File for more information.