Added ControllerResponseTrait class

system/src/Grav/Framework/Controller/Traits/ControllerResponseTrait.php

@@ -0,0 +1,183 @@
+<?php
+
+/**
+ * @package    Grav\Framework\Controller
+ *
+ * @copyright  Copyright (C) 2015 - 2019 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+declare(strict_types=1);
+
+namespace Grav\Framework\Controller\Traits;
+
+use Grav\Common\Config\Config;
+use Grav\Framework\Psr7\Response;
+use Grav\Framework\RequestHandler\Exception\RequestException;
+use Psr\Http\Message\ResponseInterface;
+use Psr\Http\Message\ServerRequestInterface;
+
+trait ControllerResponseTrait
+{
+    /**
+     * Display the current page.
+     *
+     * @return Response
+     */
+    protected function createDisplayResponse(): ResponseInterface
+    {
+        return new Response(418);
+    }
+
+    /**
+     * @param string $content
+     * @param int $code
+     * @param array $headers
+     * @return Response
+     */
+    protected function createHtmlResponse(string $content, int $code = null, array $headers = null): ResponseInterface
+    {
+        $code = $code ?? 200;
+        if ($code < 100 || $code > 599) {
+            $code = 500;
+        }
+        $headers = $headers ?? [];
+
+        return new Response($code, $headers, $content);
+    }
+
+    /**
+     * @param array $content
+     * @param int $code
+     * @param array $headers
+     * @return Response
+     */
+    protected function createJsonResponse(array $content, int $code = null, array $headers = null): ResponseInterface
+    {
+        $code = $code ?? $content['code'];
+        if (null === $code || $code < 100 || $code > 599) {
+            $code = 200;
+        }
+        $headers = ($headers ?? []) + [
+            'Content-Type' => 'application/json',
+            'Cache-Control' => 'no-cache, no-store, must-revalidate'
+        ];
+
+        return new Response($code, $headers, json_encode($content));
+    }
+
+    /**
+     * @param string $url
+     * @param int $code
+     * @return Response
+     */
+    protected function createRedirectResponse(string $url, int $code = null): ResponseInterface
+    {
+        if (null === $code || $code < 301 || $code > 307) {
+            $code = $this->getConfig()->get('system.pages.redirect_default_code', 302);
+        }
+
+        $accept = $this->getAccept(['application/json', 'text/html']);
+
+        if ($accept === 'application/json') {
+            return $this->createJsonResponse(['code' => $code, 'status' => 'redirect', 'redirect' => $url]);
+        }
+
+        return new Response($code, ['Location' => $url]);
+    }
+
+    /**
+     * @param \Exception $e
+     * @return Response
+     */
+    protected function createErrorResponse(\Exception $e): ResponseInterface
+    {
+        $validCodes = [
+            400, 401, 402, 403, 404, 405, 406, 407, 408, 409, 410, 411, 412, 413, 414, 415, 416, 417, 418,
+            422, 423, 424, 425, 426, 428, 429, 431, 451, 500, 501, 502, 503, 504, 505, 506, 507, 508, 511
+        ];
+
+        if ($e instanceof RequestException) {
+            $code = $e->getHttpCode();
+            $reason = $e->getHttpReason();
+        } else {
+            $code = $e->getCode();
+            $reason = null;
+        }
+
+        if (!in_array($code, $validCodes, true)) {
+            $code = 500;
+        }
+
+        $message = $e->getMessage();
+        $response = [
+            'code' => $code,
+            'status' => 'error',
+            'message' => $message
+        ];
+
+        $accept = $this->getAccept(['application/json', 'text/html']);
+
+        if ($accept === 'text/html') {
+            $request = $this->getRequest();
+            $method = $request->getMethod();
+
+            // On POST etc, redirect back to the previous page.
+            if ($method !== 'GET' && $method !== 'HEAD') {
+                $this->setMessage($message, 'error');
+                $referer = $request->getHeaderLine('Referer');
+                return $this->createRedirectResponse($referer, 303);
+            }
+
+            // TODO: improve error page
+            return $this->createHtmlResponse($response['message']);
+        }
+
+        return new Response($code, ['Content-Type' => 'application/json'], json_encode($response), '1.1', $reason);
+    }
+
+    protected function getAccept(array $compare)
+    {
+        $accepted = [];
+        foreach ($this->getRequest()->getHeader('Accept') as $accept) {
+            foreach (explode(',', $accept) as $item) {
+                if (!$item) {
+                    continue;
+                }
+
+                $split = explode(';q=', $item);
+                $mime = array_shift($split);
+                $priority = array_shift($split) ?? 1.0;
+
+                $accepted[$mime] = $priority;
+            }
+        }
+
+        arsort($accepted);
+
+        // TODO: add support for image/* etc
+        $list = array_intersect($compare, array_keys($accepted));
+        if (!$list && (isset($accepted['*/*']) || isset($accepted['*']))) {
+            return reset($compare);
+        }
+
+        return reset($list);
+    }
+
+    /**
+     * @return ServerRequestInterface
+     */
+    abstract protected function getRequest(): ServerRequestInterface;
+
+    /**
+     * @param string $message
+     * @param string $type
+     * @return $this
+     */
+    abstract protected function setMessage(string $message, string $type = 'info');
+
+    /**
+     * @return Config
+     */
+    abstract protected function getConfig(): Config;
+}