Merge branch 'main' into issue-3911issue-3911

1 files changed, 262 insertions, 0 deletions

diff --git a/lib/trails/Dispatcher.php b/lib/trails/Dispatcher.php
new file mode 100644
index 0000000..efa90c7
--- /dev/null
+++ b/lib/trails/Dispatcher.php
@@ -0,0 +1,262 @@
+<?php
+namespace Trails;
+
+use Trails\Exceptions\MissingFile;
+use Trails\Exceptions\RoutingError;
+use Trails\Exceptions\UnknownController;
+
+/**
+ * The Dispatcher is used to map an incoming HTTP request to a Controller
+ * producing a response which is then rendered. To initialize an instance of
+ * class Dispatcher you have to give three configuration settings:
+ *
+ *          trails_root - the absolute file path to a directory containing the
+ *                        applications controllers, views etc.
+ *           trails_uri - the URI to which routes to mapped Controller/Actions
+ *                        are appended
+ *   default_controller - the route to a controller, that is used if no
+ *                        controller is given, that is the route is equal to '/'
+ *
+ * After instantiation of a dispatcher you have to call method #dispatch with
+ * the request uri to be mapped to a controller/action pair.
+ *
+ * @package       trails
+ *
+ * @author        mlunzena
+ * @copyright (c) Authors
+ * @version       $Id: trails.php 7001 2008-04-04 11:20:27Z mlunzena $
+ */
+class Dispatcher
+{
+    # TODO (mlunzena) Konfiguration muss anders geschehen
+
+    /**
+     * This is the absolute file path to the trails application directory.
+     */
+    public string $trails_root;
+
+    /**
+     * This is the URI to which routes to controller/actions are appended.
+     */
+    public string $trails_uri;
+
+    /**
+     * This variable contains the route to the default controller.
+     */
+    public string $default_controller;
+
+    /**
+     * @param string $trails_root        absolute file path to a directory containing the
+     *                 applications controllers, views etc.
+     * @param string $trails_uri         the URI to which routes to mapped Controller/Actions
+     *                 are appended
+     * @param string $default_controller the route to a controller, that is used if no
+     *                 controller is given, that is the route is equal to '/'
+     */
+    public function __construct(
+        string $trails_root,
+        string $trails_uri,
+        string $default_controller
+    ) {
+        $this->trails_root = $trails_root;
+        $this->trails_uri = $trails_uri;
+        $this->default_controller = $default_controller;
+    }
+
+    /**
+     * Maps a string to a response which is then rendered.
+     *
+     * @param string $uri The requested URI.
+     */
+    public function dispatch($uri)
+    {
+        # E_USER_ERROR|E_USER_WARNING|E_USER_NOTICE|E_RECOVERABLE_ERROR = 5888
+        $old_handler = set_error_handler([$this, 'error_handler'], 5888);
+
+        ob_start();
+        $level = ob_get_level();
+
+        $this->map_uri_to_response($this->clean_request_uri((string) $uri))->output();
+
+        while (ob_get_level() >= $level) {
+            ob_end_flush();
+        }
+
+        if (isset($old_handler)) {
+            set_error_handler($old_handler);
+        }
+    }
+
+    /**
+     * Maps an URI to a response by figuring out first what controller to
+     * instantiate, then delegating the unconsumed part of the URI to the
+     * controller who returns an appropriate response object or throws an
+     * Exception.
+     *
+     * @param string $uri the URI string
+     * @return Response a response object
+     */
+    public function map_uri_to_response($uri)
+    {
+        try {
+            [$controller_path, $unconsumed] = '' === $uri ? $this->default_route() : $this->parse($uri);
+
+            $controller = $this->load_controller($controller_path);
+
+            $response = $controller->perform($unconsumed);
+        } catch (Exception $e) {
+            $response = isset($controller) ? $controller->rescue($e) : $this->trails_error($e);
+        }
+
+        return $response;
+    }
+
+    /**
+     * @return array  an array containing the default controller and an
+     *                empty unconsumed route
+     * @throws MissingFile
+     */
+    public function default_route()
+    {
+        if (!$this->file_exists($this->default_controller . '.php')) {
+            throw new Exceptions\MissingFile(
+                "Default controller '{$this->default_controller}' not found'"
+            );
+        }
+        return [$this->default_controller, ''];
+    }
+
+    public function trails_error($exception)
+    {
+        ob_clean();
+
+        # show details for local requests
+        $detailed = @$_SERVER['REMOTE_ADDR'] === '127.0.0.1';
+
+        $body = sprintf('<html><head><title>Trails Error</title></head>' .
+            '<body><h1>%s</h1><pre>%s</pre></body></html>',
+            htmlentities($exception->__toString()),
+            $detailed
+                ? htmlentities($exception->getTraceAsString())
+                : '');
+
+        if ($exception instanceof Exception) {
+            $response = new Response(
+                $body,
+                $exception->getHeaders(),
+                $exception->getCode(),
+                $exception->getMessage()
+            );
+        } else {
+            $response = new Response(
+                $body,
+                [],
+                500,
+                $exception->getMessage()
+            );
+        }
+
+        return $response;
+    }
+
+    /**
+     * Clean up URI string by removing the query part and leading slashes.
+     *
+     * @param string $uri an URI string
+     * @return string  the cleaned string
+     */
+    public function clean_request_uri($uri)
+    {
+        $pos = strpos($uri, '?');
+        if ($pos !== false) {
+            $uri = substr($uri, 0, $pos);
+        }
+        return ltrim($uri, '/');
+    }
+
+    /**
+     * @param string $unconsumed
+     * @param string $controller
+     * @return array
+     * @throws RoutingError
+     */
+    public function parse($unconsumed, $controller = null)
+    {
+        [$head, $tail] = $this->split_on_first_slash($unconsumed);
+
+        if (!preg_match('/^\w+$/', $head)) {
+            throw new RoutingError("No route matches '$head'");
+        }
+
+        $controller = (isset($controller) ? $controller . '/' : '') . $head;
+
+        if ($this->file_exists($controller . '.php')) {
+            return [$controller, $tail];
+        }
+
+        if ($this->file_exists($controller)) {
+            return $this->parse($tail, $controller);
+        }
+
+        throw new RoutingError("No route matches '$head'");
+    }
+
+    /**
+     * @param string $str
+     * @return array
+     */
+    public function split_on_first_slash($str)
+    {
+        preg_match(":([^/]*)(/+)?(.*):", $str, $matches);
+        return [$matches[1], $matches[3]];
+    }
+
+    /**
+     * @param string $path
+     * @return bool
+     */
+    public function file_exists($path)
+    {
+        return file_exists("{$this->trails_root}/controllers/$path");
+    }
+
+    /**
+     * Loads the controller file for a given controller path and return an
+     * instance of that controller. If an error occures, an exception will be
+     * thrown.
+     *
+     * @param string $controller the relative controller path
+     * @return Controller  an instance of that controller
+     * @throws UnknownController
+     */
+    public function load_controller($controller)
+    {
+        require_once "{$this->trails_root}/controllers/{$controller}.php";
+        $class = Inflector::camelize($controller) . 'Controller';
+        if (!class_exists($class)) {
+            throw new UnknownController("Controller missing: '$class'");
+        }
+        return new $class($this);
+    }
+
+    /**
+     * This method transforms E_USER_* and E_RECOVERABLE_ERROR to
+     * Exceptions.
+     *
+     * @param integer $errno  the level of the error raised
+     * @param string  $string the error message
+     * @param string  $file   the filename that the error was raised in
+     * @param integer $line   the line number the error was raised at
+     *
+     * @return bool
+     * @throws Exception
+     *
+     */
+    public function error_handler($errno, $string, $file, $line)
+    {
+        if (!(5888 & $errno)) {
+            return false;
+        }
+        throw new Exception(500, $string);
+    }
+}