PHP multipart form data PUT request?

问题:

I'm writing a RESTful API. I'm having trouble with uploading images using the different verbs.

Consider:

I have an object which can be created/modified/deleted/viewed via a post/put/delete/get request to a URL. The request is multi part form when there is a file to upload, or application/xml when there's just text to process.

To handle the image uploads which are associated with the object I am doing something like:

    if(isset($_FILES['userfile'])) {
        $data = $this->image_model->upload_image();
        if($data['error']){
            $this->response(array('error' => $error['error']));
        }
        $xml_data = (array)simplexml_load_string( urldecode($_POST['xml']) );           
        $object = (array)$xml_data['object'];
    } else {
        $object = $this->body('object');
    }

The major problem here is when trying to handle a put request, obviously $_POST doesn't contain the put data (as far as I can tell!).

For reference this is how I'm building the requests:

curl -F userfile=@./image.png -F xml="<xml><object>stuff to edit</object></xml>" 
  http://example.com/object -X PUT

Does anyone have any ideas how I can access the xml variable in my PUT request?

回答1:

First of all, $_FILES is not populated when handling PUT requests. It is only populated by PHP when handling POST requests.

You need to parse it manually. That goes for "regular" fields as well:

// Fetch content and determine boundary
$raw_data = file_get_contents('php://input');
$boundary = substr($raw_data, 0, strpos($raw_data, "\r\n"));

// Fetch each part
$parts = array_slice(explode($boundary, $raw_data), 1);
$data = array();

foreach ($parts as $part) {
    // If this is the last part, break
    if ($part == "--\r\n") break; 

    // Separate content from headers
    $part = ltrim($part, "\r\n");
    list($raw_headers, $body) = explode("\r\n\r\n", $part, 2);

    // Parse the headers list
    $raw_headers = explode("\r\n", $raw_headers);
    $headers = array();
    foreach ($raw_headers as $header) {
        list($name, $value) = explode(':', $header);
        $headers[strtolower($name)] = ltrim($value, ' '); 
    } 

    // Parse the Content-Disposition to get the field name, etc.
    if (isset($headers['content-disposition'])) {
        $filename = null;
        preg_match(
            '/^(.+); *name="([^"]+)"(; *filename="([^"]+)")?/', 
            $headers['content-disposition'], 
            $matches
        );
        list(, $type, $name) = $matches;
        isset($matches[4]) and $filename = $matches[4]; 

        // handle your fields here
        switch ($name) {
            // this is a file upload
            case 'userfile':
                 file_put_contents($filename, $body);
                 break;

            // default for all other files is to populate $data
            default: 
                 $data[$name] = substr($body, 0, strlen($body) - 2);
                 break;
        } 
    }

}

At each iteration, the $data array will be populated with your parameters, and the $headers array will be populated with the headers for each part (e.g.: Content-Type, etc.), and $filename will contain the original filename, if supplied in the request and is applicable to the field.

Take note the above will only work for multipart content types. Make sure to check the request Content-Type header before using the above to parse the body.

回答2:

Please don't delete this again, it's helpful to a majority of people coming here! All previous answers were partial answers that don't cover the solution as a majority of people asking this question would want.

This takes what has been said above and additionally handles multiple file uploads and places them in $_FILES as someone would expect. To get this to work, you have to add 'Script PUT /put.php' to your Virtual Host for the project per Documentation. I also suspect I'll have to setup a cron to cleanup any '.tmp' files.

private function _parsePut(  )
{
    global $_PUT;

    /* PUT data comes in on the stdin stream */
    $putdata = fopen("php://input", "r");

    /* Open a file for writing */
    // $fp = fopen("myputfile.ext", "w");

    $raw_data = '';

    /* Read the data 1 KB at a time
       and write to the file */
    while ($chunk = fread($putdata, 1024))
        $raw_data .= $chunk;

    /* Close the streams */
    fclose($putdata);

    // Fetch content and determine boundary
    $boundary = substr($raw_data, 0, strpos($raw_data, "\r\n"));

    if(empty($boundary)){
        parse_str($raw_data,$data);
        $GLOBALS[ '_PUT' ] = $data;
        return;
    }

    // Fetch each part
    $parts = array_slice(explode($boundary, $raw_data), 1);
    $data = array();

    foreach ($parts as $part) {
        // If this is the last part, break
        if ($part == "--\r\n") break;

        // Separate content from headers
        $part = ltrim($part, "\r\n");
        list($raw_headers, $body) = explode("\r\n\r\n", $part, 2);

        // Parse the headers list
        $raw_headers = explode("\r\n", $raw_headers);
        $headers = array();
        foreach ($raw_headers as $header) {
            list($name, $value) = explode(':', $header);
            $headers[strtolower($name)] = ltrim($value, ' ');
        }

        // Parse the Content-Disposition to get the field name, etc.
        if (isset($headers['content-disposition'])) {
            $filename = null;
            $tmp_name = null;
            preg_match(
                '/^(.+); *name="([^"]+)"(; *filename="([^"]+)")?/',
                $headers['content-disposition'],
                $matches
            );
            list(, $type, $name) = $matches;

            //Parse File
            if( isset($matches[4]) )
            {
                //if labeled the same as previous, skip
                if( isset( $_FILES[ $matches[ 2 ] ] ) )
                {
                    continue;
                }

                //get filename
                $filename = $matches[4];

                //get tmp name
                $filename_parts = pathinfo( $filename );
                $tmp_name = tempnam( ini_get('upload_tmp_dir'), $filename_parts['filename']);

                //populate $_FILES with information, size may be off in multibyte situation
                $_FILES[ $matches[ 2 ] ] = array(
                    'error'=>0,
                    'name'=>$filename,
                    'tmp_name'=>$tmp_name,
                    'size'=>strlen( $body ),
                    'type'=>$value
                );

                //place in temporary directory
                file_put_contents($tmp_name, $body);
            }
            //Parse Field
            else
            {
                $data[$name] = substr($body, 0, strlen($body) - 2);
            }
        }

    }
    $GLOBALS[ '_PUT' ] = $data;
    return;
}

回答3:

Quoting netcoder reply : "Take note the above will only work for multipart content types"

To work with any content type I have added the following lines to Mr. netcoder's solution :

   // Fetch content and determine boundary
   $raw_data = file_get_contents('php://input');
   $boundary = substr($raw_data, 0, strpos($raw_data, "\r\n"));

   /*...... My edit --------- */
    if(empty($boundary)){
        parse_str($raw_data,$data);
        return $data;
    }
   /* ........... My edit ends ......... */
    // Fetch each part
    $parts = array_slice(explode($boundary, $raw_data), 1);
    $data = array();
    ............
    ...............