1<?php
2
3/*
4 * This file is part of the Symfony package.
5 *
6 * (c) Fabien Potencier <fabien@symfony.com>
7 *
8 * For the full copyright and license information, please view the LICENSE
9 * file that was distributed with this source code.
10 */
11
12namespace Symfony\Component\HttpKernel\HttpCache;
13
14use Symfony\Component\HttpFoundation\Request;
15use Symfony\Component\HttpFoundation\Response;
16use Symfony\Component\HttpKernel\HttpKernelInterface;
17
18/**
19 * Abstract class implementing Surrogate capabilities to Request and Response instances.
20 *
21 * @author Fabien Potencier <fabien@symfony.com>
22 * @author Robin Chalas <robin.chalas@gmail.com>
23 */
24abstract class AbstractSurrogate implements SurrogateInterface
25{
26    protected $contentTypes;
27    protected $phpEscapeMap = [
28        ['<?', '<%', '<s', '<S'],
29        ['<?php echo "<?"; ?>', '<?php echo "<%"; ?>', '<?php echo "<s"; ?>', '<?php echo "<S"; ?>'],
30    ];
31
32    /**
33     * @param array $contentTypes An array of content-type that should be parsed for Surrogate information
34     *                            (default: text/html, text/xml, application/xhtml+xml, and application/xml)
35     */
36    public function __construct(array $contentTypes = ['text/html', 'text/xml', 'application/xhtml+xml', 'application/xml'])
37    {
38        $this->contentTypes = $contentTypes;
39    }
40
41    /**
42     * Returns a new cache strategy instance.
43     *
44     * @return ResponseCacheStrategyInterface A ResponseCacheStrategyInterface instance
45     */
46    public function createCacheStrategy()
47    {
48        return new ResponseCacheStrategy();
49    }
50
51    /**
52     * {@inheritdoc}
53     */
54    public function hasSurrogateCapability(Request $request)
55    {
56        if (null === $value = $request->headers->get('Surrogate-Capability')) {
57            return false;
58        }
59
60        return false !== strpos($value, sprintf('%s/1.0', strtoupper($this->getName())));
61    }
62
63    /**
64     * {@inheritdoc}
65     */
66    public function addSurrogateCapability(Request $request)
67    {
68        $current = $request->headers->get('Surrogate-Capability');
69        $new = sprintf('symfony="%s/1.0"', strtoupper($this->getName()));
70
71        $request->headers->set('Surrogate-Capability', $current ? $current.', '.$new : $new);
72    }
73
74    /**
75     * {@inheritdoc}
76     */
77    public function needsParsing(Response $response)
78    {
79        if (!$control = $response->headers->get('Surrogate-Control')) {
80            return false;
81        }
82
83        $pattern = sprintf('#content="[^"]*%s/1.0[^"]*"#', strtoupper($this->getName()));
84
85        return (bool) preg_match($pattern, $control);
86    }
87
88    /**
89     * {@inheritdoc}
90     */
91    public function handle(HttpCache $cache, $uri, $alt, $ignoreErrors)
92    {
93        $subRequest = Request::create($uri, Request::METHOD_GET, [], $cache->getRequest()->cookies->all(), [], $cache->getRequest()->server->all());
94
95        try {
96            $response = $cache->handle($subRequest, HttpKernelInterface::SUB_REQUEST, true);
97
98            if (!$response->isSuccessful()) {
99                throw new \RuntimeException(sprintf('Error when rendering "%s" (Status code is %d).', $subRequest->getUri(), $response->getStatusCode()));
100            }
101
102            return $response->getContent();
103        } catch (\Exception $e) {
104            if ($alt) {
105                return $this->handle($cache, $alt, '', $ignoreErrors);
106            }
107
108            if (!$ignoreErrors) {
109                throw $e;
110            }
111        }
112
113        return '';
114    }
115
116    /**
117     * Remove the Surrogate from the Surrogate-Control header.
118     */
119    protected function removeFromControl(Response $response)
120    {
121        if (!$response->headers->has('Surrogate-Control')) {
122            return;
123        }
124
125        $value = $response->headers->get('Surrogate-Control');
126        $upperName = strtoupper($this->getName());
127
128        if (sprintf('content="%s/1.0"', $upperName) == $value) {
129            $response->headers->remove('Surrogate-Control');
130        } elseif (preg_match(sprintf('#,\s*content="%s/1.0"#', $upperName), $value)) {
131            $response->headers->set('Surrogate-Control', preg_replace(sprintf('#,\s*content="%s/1.0"#', $upperName), '', $value));
132        } elseif (preg_match(sprintf('#content="%s/1.0",\s*#', $upperName), $value)) {
133            $response->headers->set('Surrogate-Control', preg_replace(sprintf('#content="%s/1.0",\s*#', $upperName), '', $value));
134        }
135    }
136}
137