League\Tactician\CommandBus

Complexity

Total Complexity

4

Size/Duplication

Total Lines	32
Duplicated Lines	0 %

Test Coverage

Coverage

100%

Importance

Changes	5
Bugs	1	Features	0

3 Methods

Rating	Name	Duplication	Size	Complexity
A	__construct()	0	3	1
A	handle()	0	3	1
A	createExecutionChain()	0	9	2

<?php

declare(strict_types=1);

namespace League\Tactician;

use Closure;

use function array_pop;

/**
 * Receives a command and sends it through a chain of middleware for processing.
 */
final class CommandBus
{
    /** @var Closure(object $command):mixed */
    private Closure $middlewareChain;

    public function __construct(Middleware ...$middleware)
    {
        $this->middlewareChain = $this->createExecutionChain($middleware);
    }

    /**
     * Executes the given command and optionally returns a value
     *
     * @return mixed
     */
    public function handle(object $command)
    {
        return ($this->middlewareChain)($command);
    }

    /**
     * @param Middleware[] $middlewareList
     */
    private function createExecutionChain(array $middlewareList): Closure
    {
        $lastCallable = static fn () => null;

        while ($middleware = array_pop($middlewareList)) {
            $lastCallable = static fn (object $command) => $middleware->execute($command, $lastCallable);
        }

        return $lastCallable;
    }
}