Developer
<?php
declare(strict_types=1);
namespace GuzzleHttp\Psr7;
use Psr\Http\Message\StreamInterface;
/**
* Stream that when read returns bytes for a streaming multipart or
* multipart/form-data stream.
*/
final class MultipartStream implements StreamInterface
{
use StreamDecoratorTrait;
/** @var string */
private $boundary;
/** @var StreamInterface */
private $stream;
/**
* @param array $elements Array of associative arrays, each containing a
* required "name" key mapping to the form field,
* name, a required "contents" key mapping to a
* StreamInterface/resource/string, an optional
* "headers" associative array of custom headers,
* and an optional "filename" key mapping to a
* string to send as the filename in the part.
* @param string $boundary You can optionally provide a specific boundary
*
* @throws \InvalidArgumentException
*/
public function __construct(array $elements = [], string $boundary = null)
{
$this->boundary = $boundary ?: bin2hex(random_bytes(20));
$this->stream = $this->createStream($elements);
}
public function getBoundary(): string
{
return $this->boundary;
}
public function isWritable(): bool
{
return false;
}
/**
* Get the headers needed before transferring the content of a POST file
*
* @param string[] $headers
*/
private function getHeaders(array $headers): string
{
$str = '';
foreach ($headers as $key => $value) {
$str .= "{$key}: {$value}\r\n";
}
return "--{$this->boundary}\r\n".trim($str)."\r\n\r\n";
}
/**
* Create the aggregate stream that will be used to upload the POST data
*/
protected function createStream(array $elements = []): StreamInterface
{
$stream = new AppendStream();
foreach ($elements as $element) {
if (!is_array($element)) {
throw new \UnexpectedValueException('An array is expected');
}
$this->addElement($stream, $element);
}
// Add the trailing boundary with CRLF
$stream->addStream(Utils::streamFor("--{$this->boundary}--\r\n"));
return $stream;
}
private function addElement(AppendStream $stream, array $element): void
{
foreach (['contents', 'name'] as $key) {
if (!array_key_exists($key, $element)) {
throw new \InvalidArgumentException("A '{$key}' key is required");
}
}
$element['contents'] = Utils::streamFor($element['contents']);
if (empty($element['filename'])) {
$uri = $element['contents']->getMetadata('uri');
if ($uri && \is_string($uri) && \substr($uri, 0, 6) !== 'php://' && \substr($uri, 0, 7) !== 'data://') {
$element['filename'] = $uri;
}
}
[$body, $headers] = $this->createElement(
$element['name'],
$element['contents'],
$element['filename'] ?? null,
$element['headers'] ?? []
);
$stream->addStream(Utils::streamFor($this->getHeaders($headers)));
$stream->addStream($body);
$stream->addStream(Utils::streamFor("\r\n"));
}
/**
* @param string[] $headers
*
* @return array{0: StreamInterface, 1: string[]}
*/
private function createElement(string $name, StreamInterface $stream, ?string $filename, array $headers): array
{
// Set a default content-disposition header if one was no provided
$disposition = self::getHeader($headers, 'content-disposition');
if (!$disposition) {
$headers['Content-Disposition'] = ($filename === '0' || $filename)
? sprintf(
'form-data; name="%s"; filename="%s"',
$name,
basename($filename)
)
: "form-data; name=\"{$name}\"";
}
// Set a default content-length header if one was no provided
$length = self::getHeader($headers, 'content-length');
if (!$length) {
if ($length = $stream->getSize()) {
$headers['Content-Length'] = (string) $length;
}
}
// Set a default Content-Type if one was not supplied
$type = self::getHeader($headers, 'content-type');
if (!$type && ($filename === '0' || $filename)) {
$headers['Content-Type'] = MimeType::fromFilename($filename) ?? 'application/octet-stream';
}
return [$stream, $headers];
}
/**
* @param string[] $headers
*/
private static function getHeader(array $headers, string $key): ?string
{
$lowercaseHeader = strtolower($key);
foreach ($headers as $k => $v) {
if (strtolower((string) $k) === $lowercaseHeader) {
return $v;
}
}
return null;
}
}
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To ensure a smooth integration process and optimal performance, follow these best practices: