在 PHP 中使用 cURL 发布文件字符串？

Question

我想知道当文件只是一个字符串时是否可以发布文件 - 以及其他表单数据？

我知道您可以通过在文件路径前加上“@”前缀来发布文件系统上已有的文件。

但是我想绕过创建临时文件并仅将文件作为字符串发送，但我不确定如何在 PHP 中使用 cURL 构造请求。

干杯

    $postFields = array(
        'otherFields'   => 'Yes'
        ,'filename'     => 'my_file.csv'
        ,'data'         => 'comma seperated content'
    );

    $options = array(
        CURLOPT_RETURNTRANSFER  => true
        ,CURLOPT_SSL_VERIFYPEER => false
        ,CURLOPT_SSL_VERIFYHOST => 1
        ,CURLOPT_POSTFIELDS     => $postFields
        ,CURLOPT_HTTPHEADER     => array(
            'Content-type: multipart/form-data'
        )
    );

Answer 1

应该可以：这是一个通过浏览器发布的表单（省略不相关的字段）：

POST http://host.example.com/somewhere HTTP/1.1
Content-Type: multipart/form-data; boundary=---------------------------7da16b2e4026c
Content-Length: 105732

-----------------------------7da16b2e4026c
Content-Disposition: form-data; name="NewFile"; filename="test.jpg"
Content-Type: image/jpeg

(...raw JPEG data here...)
-----------------------------7da16b2e4026c
Content-Disposition: form-data; name="otherformfield"

content of otherformfield is this text
-----------------------------7da16b2e4026c--

因此，如果我们自己构建 POST 主体并设置一两个额外的标头，我们应该能够模拟这一点：

// form field separator
$delimiter = '-------------' . uniqid();
// file upload fields: name => array(type=>'mime/type',content=>'raw data')
$fileFields = array(
    'file1' => array(
        'type' => 'text/plain',
        'content' => '...your raw file content goes here...'
    ), /* ... */
);
// all other fields (not file upload): name => value
$postFields = array(
    'otherformfield'   => 'content of otherformfield is this text',
    /* ... */
);

$data = '';

// populate normal fields first (simpler)
foreach ($postFields as $name => $content) {
   $data .= "--" . $delimiter . "\r\n";
    $data .= 'Content-Disposition: form-data; name="' . $name . '"';
    // note: double endline
    $data .= "\r\n\r\n";
}
// populate file fields
foreach ($fileFields as $name => $file) {
    $data .= "--" . $delimiter . "\r\n";
    // "filename" attribute is not essential; server-side scripts may use it
    $data .= 'Content-Disposition: form-data; name="' . $name . '";' .
             ' filename="' . $name . '"' . "\r\n";
    // this is, again, informative only; good practice to include though
    $data .= 'Content-Type: ' . $file['type'] . "\r\n";
    // this endline must be here to indicate end of headers
    $data .= "\r\n";
    // the file itself (note: there's no encoding of any kind)
    $data .= $file['content'] . "\r\n";
}
// last delimiter
$data .= "--" . $delimiter . "--\r\n";

$handle = curl_init($url);
curl_setopt($handle, CURLOPT_POST, true);
curl_setopt($handle, CURLOPT_HTTPHEADER , array(
    'Content-Type: multipart/form-data; boundary=' . $delimiter,
    'Content-Length: ' . strlen($data)));  
curl_setopt($handle, CURLOPT_POSTFIELDS, $data);
curl_exec($handle);

这样，我们就可以自己完成所有繁重的工作，并相信 cURL 不会破坏它。

Answer 2

PHP 可以访问临时位置“php://memory”，这实际上使您想要做的事情变得相当容易。

$fileHandle = fopen('php://memory', 'rw');
fwrite($fileHandle, $content);
rewind($fileHandle);

$options = array(
    CURLOPT_RETURNTRANSFER  => true
    ,CURLOPT_SSL_VERIFYPEER => false
    ,CURLOPT_SSL_VERIFYHOST => 1
    ,CURLOPT_HTTPHEADER     => array(
        'Content-type: multipart/form-data',
    )
    ,CURLOPT_INFILE         => $fileHandle
    ,CURLOPT_INFILESIZE     => strlen($content)
);

Answer 3

PHP 8.1 为此提供了一个新的

CURLStringFile

类：

$csv_content = 'comma,separated,content\nfoo,bar,baz';
$post_fields = array(
    'file' => new CURLStringFile($csv_content, 'my_file.csv', 'text/csv')
);

$ch = curl_init();

curl_setopt($ch, CURLOPT_URL, 'http://example.com/');
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, $post_fields);