1<?php
2
3declare(strict_types=1);
4
5namespace GuzzleHttp\Psr7;
6
7use Psr\Http\Message\MessageInterface;
8use Psr\Http\Message\RequestInterface;
9use Psr\Http\Message\ResponseInterface;
10
11final class Message
12{
13    /**
14     * Returns the string representation of an HTTP message.
15     *
16     * @param MessageInterface $message Message to convert to a string.
17     */
18    public static function toString(MessageInterface $message): string
19    {
20        if ($message instanceof RequestInterface) {
21            $msg = trim($message->getMethod() . ' '
22                    . $message->getRequestTarget())
23                . ' HTTP/' . $message->getProtocolVersion();
24            if (!$message->hasHeader('host')) {
25                $msg .= "\r\nHost: " . $message->getUri()->getHost();
26            }
27        } elseif ($message instanceof ResponseInterface) {
28            $msg = 'HTTP/' . $message->getProtocolVersion() . ' '
29                . $message->getStatusCode() . ' '
30                . $message->getReasonPhrase();
31        } else {
32            throw new \InvalidArgumentException('Unknown message type');
33        }
34
35        foreach ($message->getHeaders() as $name => $values) {
36            if (strtolower($name) === 'set-cookie') {
37                foreach ($values as $value) {
38                    $msg .= "\r\n{$name}: " . $value;
39                }
40            } else {
41                $msg .= "\r\n{$name}: " . implode(', ', $values);
42            }
43        }
44
45        return "{$msg}\r\n\r\n" . $message->getBody();
46    }
47
48    /**
49     * Get a short summary of the message body.
50     *
51     * Will return `null` if the response is not printable.
52     *
53     * @param MessageInterface $message    The message to get the body summary
54     * @param int              $truncateAt The maximum allowed size of the summary
55     */
56    public static function bodySummary(MessageInterface $message, int $truncateAt = 120): ?string
57    {
58        $body = $message->getBody();
59
60        if (!$body->isSeekable() || !$body->isReadable()) {
61            return null;
62        }
63
64        $size = $body->getSize();
65
66        if ($size === 0) {
67            return null;
68        }
69
70        $summary = $body->read($truncateAt);
71        $body->rewind();
72
73        if ($size > $truncateAt) {
74            $summary .= ' (truncated...)';
75        }
76
77        // Matches any printable character, including unicode characters:
78        // letters, marks, numbers, punctuation, spacing, and separators.
79        if (preg_match('/[^\pL\pM\pN\pP\pS\pZ\n\r\t]/u', $summary)) {
80            return null;
81        }
82
83        return $summary;
84    }
85
86    /**
87     * Attempts to rewind a message body and throws an exception on failure.
88     *
89     * The body of the message will only be rewound if a call to `tell()`
90     * returns a value other than `0`.
91     *
92     * @param MessageInterface $message Message to rewind
93     *
94     * @throws \RuntimeException
95     */
96    public static function rewindBody(MessageInterface $message): void
97    {
98        $body = $message->getBody();
99
100        if ($body->tell()) {
101            $body->rewind();
102        }
103    }
104
105    /**
106     * Parses an HTTP message into an associative array.
107     *
108     * The array contains the "start-line" key containing the start line of
109     * the message, "headers" key containing an associative array of header
110     * array values, and a "body" key containing the body of the message.
111     *
112     * @param string $message HTTP request or response to parse.
113     */
114    public static function parseMessage(string $message): array
115    {
116        if (!$message) {
117            throw new \InvalidArgumentException('Invalid message');
118        }
119
120        $message = ltrim($message, "\r\n");
121
122        $messageParts = preg_split("/\r?\n\r?\n/", $message, 2);
123
124        if ($messageParts === false || count($messageParts) !== 2) {
125            throw new \InvalidArgumentException('Invalid message: Missing header delimiter');
126        }
127
128        [$rawHeaders, $body] = $messageParts;
129        $rawHeaders .= "\r\n"; // Put back the delimiter we split previously
130        $headerParts = preg_split("/\r?\n/", $rawHeaders, 2);
131
132        if ($headerParts === false || count($headerParts) !== 2) {
133            throw new \InvalidArgumentException('Invalid message: Missing status line');
134        }
135
136        [$startLine, $rawHeaders] = $headerParts;
137
138        if (preg_match("/(?:^HTTP\/|^[A-Z]+ \S+ HTTP\/)(\d+(?:\.\d+)?)/i", $startLine, $matches) && $matches[1] === '1.0') {
139            // Header folding is deprecated for HTTP/1.1, but allowed in HTTP/1.0
140            $rawHeaders = preg_replace(Rfc7230::HEADER_FOLD_REGEX, ' ', $rawHeaders);
141        }
142
143        /** @var array[] $headerLines */
144        $count = preg_match_all(Rfc7230::HEADER_REGEX, $rawHeaders, $headerLines, PREG_SET_ORDER);
145
146        // If these aren't the same, then one line didn't match and there's an invalid header.
147        if ($count !== substr_count($rawHeaders, "\n")) {
148            // Folding is deprecated, see https://tools.ietf.org/html/rfc7230#section-3.2.4
149            if (preg_match(Rfc7230::HEADER_FOLD_REGEX, $rawHeaders)) {
150                throw new \InvalidArgumentException('Invalid header syntax: Obsolete line folding');
151            }
152
153            throw new \InvalidArgumentException('Invalid header syntax');
154        }
155
156        $headers = [];
157
158        foreach ($headerLines as $headerLine) {
159            $headers[$headerLine[1]][] = $headerLine[2];
160        }
161
162        return [
163            'start-line' => $startLine,
164            'headers' => $headers,
165            'body' => $body,
166        ];
167    }
168
169    /**
170     * Constructs a URI for an HTTP request message.
171     *
172     * @param string $path    Path from the start-line
173     * @param array  $headers Array of headers (each value an array).
174     */
175    public static function parseRequestUri(string $path, array $headers): string
176    {
177        $hostKey = array_filter(array_keys($headers), function ($k) {
178            return strtolower($k) === 'host';
179        });
180
181        // If no host is found, then a full URI cannot be constructed.
182        if (!$hostKey) {
183            return $path;
184        }
185
186        $host = $headers[reset($hostKey)][0];
187        $scheme = substr($host, -4) === ':443' ? 'https' : 'http';
188
189        return $scheme . '://' . $host . '/' . ltrim($path, '/');
190    }
191
192    /**
193     * Parses a request message string into a request object.
194     *
195     * @param string $message Request message string.
196     */
197    public static function parseRequest(string $message): RequestInterface
198    {
199        $data = self::parseMessage($message);
200        $matches = [];
201        if (!preg_match('/^[\S]+\s+([a-zA-Z]+:\/\/|\/).*/', $data['start-line'], $matches)) {
202            throw new \InvalidArgumentException('Invalid request string');
203        }
204        $parts = explode(' ', $data['start-line'], 3);
205        $version = isset($parts[2]) ? explode('/', $parts[2])[1] : '1.1';
206
207        $request = new Request(
208            $parts[0],
209            $matches[1] === '/' ? self::parseRequestUri($parts[1], $data['headers']) : $parts[1],
210            $data['headers'],
211            $data['body'],
212            $version
213        );
214
215        return $matches[1] === '/' ? $request : $request->withRequestTarget($parts[1]);
216    }
217
218    /**
219     * Parses a response message string into a response object.
220     *
221     * @param string $message Response message string.
222     */
223    public static function parseResponse(string $message): ResponseInterface
224    {
225        $data = self::parseMessage($message);
226        // According to https://tools.ietf.org/html/rfc7230#section-3.1.2 the space
227        // between status-code and reason-phrase is required. But browsers accept
228        // responses without space and reason as well.
229        if (!preg_match('/^HTTP\/.* [0-9]{3}( .*|$)/', $data['start-line'])) {
230            throw new \InvalidArgumentException('Invalid response string: ' . $data['start-line']);
231        }
232        $parts = explode(' ', $data['start-line'], 3);
233
234        return new Response(
235            (int) $parts[1],
236            $data['headers'],
237            $data['body'],
238            explode('/', $parts[0])[1],
239            $parts[2] ?? null
240        );
241    }
242}
243