Scaffold miniroute routing/middleware kernel

2 files changed, 56 insertions, 0 deletions

diff --git a/src/Middleware/MiddlewareInterface.php b/src/Middleware/MiddlewareInterface.php
new file mode 100644
index 0000000..3d21a3f
--- /dev/null
+++ b/src/Middleware/MiddlewareInterface.php
@@ -0,0 +1,21 @@
+<?php
+
+declare(strict_types=1);
+
+namespace BrettParson\MiniRoute\Middleware;
+
+use BrettParson\MiniRoute\Http\RequestInterface;
+use BrettParson\MiniRoute\Http\ResponseInterface;
+
+interface MiddlewareInterface
+{
+    /**
+     * Process the request and either short-circuit with a Response or pass
+     * control to $next.
+     *
+     * Middleware may wrap $next to post-process the response.
+     *
+     * @param callable(RequestInterface): ResponseInterface $next
+     */
+    public function handle(RequestInterface $request, callable $next): ResponseInterface;
+}
diff --git a/src/Middleware/MiddlewarePipeline.php b/src/Middleware/MiddlewarePipeline.php
new file mode 100644
index 0000000..65a300e
--- /dev/null
+++ b/src/Middleware/MiddlewarePipeline.php
@@ -0,0 +1,35 @@
+<?php
+
+declare(strict_types=1);
+
+namespace BrettParson\MiniRoute\Middleware;
+
+use BrettParson\MiniRoute\Http\RequestInterface;
+use BrettParson\MiniRoute\Http\ResponseInterface;
+
+final class MiddlewarePipeline
+{
+    /**
+     * Wrap a core handler with an ordered list of middleware instances.
+     *
+     * The first middleware in $middleware becomes the outermost layer, so a
+     * request flows through it first and its response post-processing runs
+     * last.
+     *
+     * @param list<MiddlewareInterface> $middleware
+     * @param callable(RequestInterface): ResponseInterface $core
+     * @return callable(RequestInterface): ResponseInterface
+     */
+    public static function compose(array $middleware, callable $core): callable
+    {
+        foreach (array_reverse($middleware) as $middlewareInstance) {
+            $next = $core;
+
+            $core = static function (RequestInterface $request) use ($middlewareInstance, $next): ResponseInterface {
+                return $middlewareInstance->handle($request, $next);
+            };
+        }
+
+        return $core;
+    }
+}