1<?php
2
3namespace GuzzleHttp\Psr7;
4
5use Psr\Http\Message\StreamInterface;
6
7/**
8 * Stream that when read returns bytes for a streaming multipart or
9 * multipart/form-data stream.
10 *
11 * @final
12 */
13class MultipartStream implements StreamInterface
14{
15    use StreamDecoratorTrait;
16
17    private $boundary;
18
19    /**
20     * @param array  $elements Array of associative arrays, each containing a
21     *                         required "name" key mapping to the form field,
22     *                         name, a required "contents" key mapping to a
23     *                         StreamInterface/resource/string, an optional
24     *                         "headers" associative array of custom headers,
25     *                         and an optional "filename" key mapping to a
26     *                         string to send as the filename in the part.
27     * @param string $boundary You can optionally provide a specific boundary
28     *
29     * @throws \InvalidArgumentException
30     */
31    public function __construct(array $elements = [], $boundary = null)
32    {
33        $this->boundary = $boundary ?: sha1(uniqid('', true));
34        $this->stream = $this->createStream($elements);
35    }
36
37    /**
38     * Get the boundary
39     *
40     * @return string
41     */
42    public function getBoundary()
43    {
44        return $this->boundary;
45    }
46
47    public function isWritable()
48    {
49        return false;
50    }
51
52    /**
53     * Get the headers needed before transferring the content of a POST file
54     */
55    private function getHeaders(array $headers)
56    {
57        $str = '';
58        foreach ($headers as $key => $value) {
59            $str .= "{$key}: {$value}\r\n";
60        }
61
62        return "--{$this->boundary}\r\n" . trim($str) . "\r\n\r\n";
63    }
64
65    /**
66     * Create the aggregate stream that will be used to upload the POST data
67     */
68    protected function createStream(array $elements)
69    {
70        $stream = new AppendStream();
71
72        foreach ($elements as $element) {
73            $this->addElement($stream, $element);
74        }
75
76        // Add the trailing boundary with CRLF
77        $stream->addStream(Utils::streamFor("--{$this->boundary}--\r\n"));
78
79        return $stream;
80    }
81
82    private function addElement(AppendStream $stream, array $element)
83    {
84        foreach (['contents', 'name'] as $key) {
85            if (!array_key_exists($key, $element)) {
86                throw new \InvalidArgumentException("A '{$key}' key is required");
87            }
88        }
89
90        $element['contents'] = Utils::streamFor($element['contents']);
91
92        if (empty($element['filename'])) {
93            $uri = $element['contents']->getMetadata('uri');
94            if (substr($uri, 0, 6) !== 'php://') {
95                $element['filename'] = $uri;
96            }
97        }
98
99        list($body, $headers) = $this->createElement(
100            $element['name'],
101            $element['contents'],
102            isset($element['filename']) ? $element['filename'] : null,
103            isset($element['headers']) ? $element['headers'] : []
104        );
105
106        $stream->addStream(Utils::streamFor($this->getHeaders($headers)));
107        $stream->addStream($body);
108        $stream->addStream(Utils::streamFor("\r\n"));
109    }
110
111    /**
112     * @return array
113     */
114    private function createElement($name, StreamInterface $stream, $filename, array $headers)
115    {
116        // Set a default content-disposition header if one was no provided
117        $disposition = $this->getHeader($headers, 'content-disposition');
118        if (!$disposition) {
119            $headers['Content-Disposition'] = ($filename === '0' || $filename)
120                ? sprintf(
121                    'form-data; name="%s"; filename="%s"',
122                    $name,
123                    basename($filename)
124                )
125                : "form-data; name=\"{$name}\"";
126        }
127
128        // Set a default content-length header if one was no provided
129        $length = $this->getHeader($headers, 'content-length');
130        if (!$length) {
131            if ($length = $stream->getSize()) {
132                $headers['Content-Length'] = (string) $length;
133            }
134        }
135
136        // Set a default Content-Type if one was not supplied
137        $type = $this->getHeader($headers, 'content-type');
138        if (!$type && ($filename === '0' || $filename)) {
139            if ($type = MimeType::fromFilename($filename)) {
140                $headers['Content-Type'] = $type;
141            }
142        }
143
144        return [$stream, $headers];
145    }
146
147    private function getHeader(array $headers, $key)
148    {
149        $lowercaseHeader = strtolower($key);
150        foreach ($headers as $k => $v) {
151            if (strtolower($k) === $lowercaseHeader) {
152                return $v;
153            }
154        }
155
156        return null;
157    }
158}
159