Merge pull request #9 from Minstel/middleware-base-path

'Base Path' middleware

1 files changed, 118 insertions, 0 deletions

diff --git a/src/Router/Middleware/BasePath.php b/src/Router/Middleware/BasePath.php
new file mode 100644
index 0000000..a80d029
--- /dev/null
+++ b/src/Router/Middleware/BasePath.php
@@ -0,0 +1,118 @@
+<?php
+
+namespace Jasny\Router\Middleware;
+
+use Psr\Http\Message\ServerRequestInterface;
+use Psr\Http\Message\ResponseInterface;
+
+/**
+ * Set base path for request
+ */
+class BasePath
+{    
+    /**
+     * Base path
+     * @var string
+     **/
+    protected $basePath = '';
+
+    /**
+     * Set base path
+     *
+     * @param string $basePath
+     */
+    public function __construct($basePath)
+    {
+        if (!$basePath || !is_string($basePath) || $basePath === '/') {
+            throw new \InvalidArgumentException("Base path must be a string with at list one url segment");
+        }
+
+        $this->basePath = $this->normalizePath($basePath);
+    }
+
+    /**
+     * Get base path
+     *
+     * @return string
+     */
+    public function getBasePath()
+    {
+        return $this->basePath;
+    }
+
+    /**
+     * Run middleware action
+     *
+     * @param ServerRequestInterface $request
+     * @param ResponseInterface      $response
+     * @param callback               $next
+     * @return ResponseInterface
+     */
+    public function __invoke(ServerRequestInterface $request, ResponseInterface $response, $next)
+    {
+        if (!is_callable($next)) {
+            throw new \InvalidArgumentException("'next' should be a callback");            
+        }
+
+        $uri = $request->getUri();
+        $path = $this->normalizePath($uri->getPath());
+
+        if (!$this->hasBasePath($path)) return $this->setError($response);
+
+        $noBase = $this->getBaselessPath($path);
+        $noBaseUri = $uri->withPath($noBase);        
+        $request = $request->withUri($noBaseUri)->withAttribute('original_uri', $uri);
+
+        return call_user_func($next, $request, $response);
+    }
+
+    /**
+     * Remove base path from given path
+     *
+     * @param string $path
+     * @return string
+     */
+    protected function getBaselessPath($path)
+    {
+        return substr($path, strlen($this->getBasePath())) ?: '/';
+    }
+
+    /**
+     * Normalize path
+     *
+     * @param string $path
+     * @return string
+     */
+    protected function normalizePath($path)
+    {
+        return '/' . ltrim($path, '/');
+    }
+
+    /**
+     * Check that path starts with base path
+     *
+     * @param string $path
+     * @return boolean
+     */
+    protected function hasBasePath($path)
+    {
+        return strpos($path . '/', $this->getBasePath() . '/') === 0;
+    }
+
+    /**
+     * Set error response
+     *
+     * @param ResponseInterface $response
+     * @return ResponseInterface
+     */
+    protected function setError($response)
+    {
+        $message = 'Not Found';
+
+        $body = $response->getBody();        
+        $body->rewind();
+        $body->write($message);
+
+        return $response->withStatus(404, $message)->withBody($body);
+    }
+}