Remote file size without downloading file

Question

Is there a way to get the size of a remote file http://my_url/my_file.txt without downloading the file?

Answer 1

Try this: I use it and got good result.

    function getRemoteFilesize($url)
{
    $file_headers = @get_headers($url, 1);
    if($size =getSize($file_headers)){
return $size;
    } elseif($file_headers[0] == "HTTP/1.1 302 Found"){
        if (isset($file_headers["Location"])) {
            $url = $file_headers["Location"][0];
            if (strpos($url, "/_as/") !== false) {
                $url = substr($url, 0, strpos($url, "/_as/"));
            }
            $file_headers = @get_headers($url, 1);
            return getSize($file_headers);
        }
    }
    return false;
}

function getSize($file_headers){

    if (!$file_headers || $file_headers[0] == "HTTP/1.1 404 Not Found" || $file_headers[0] == "HTTP/1.0 404 Not Found") {
        return false;
    } elseif ($file_headers[0] == "HTTP/1.0 200 OK" || $file_headers[0] == "HTTP/1.1 200 OK") {

        $clen=(isset($file_headers['Content-Length']))?$file_headers['Content-Length']:false;
        $size = $clen;
        if($clen) {
            switch ($clen) {
                case $clen < 1024:
                    $size = $clen . ' B';
                    break;
                case $clen < 1048576:
                    $size = round($clen / 1024, 2) . ' KiB';
                    break;
                case $clen < 1073741824:
                    $size = round($clen / 1048576, 2) . ' MiB';
                    break;
                case $clen < 1099511627776:
                    $size = round($clen / 1073741824, 2) . ' GiB';
                    break;
            }
        }
        return $size;

    }
    return false;
}

Now, test like these:

echo getRemoteFilesize('http://mandasoy.com/wp-content/themes/spacious/images/plain.png').PHP_EOL;
echo getRemoteFilesize('http://bookfi.net/dl/201893/e96818').PHP_EOL;
echo getRemoteFilesize('https://stackoverflow.com/questions/14679268/downloading-files-as-attachment-filesize-incorrect').PHP_EOL;

Results:

24.82 KiB

912 KiB

101.85 KiB

Answer 2

Here is another approach that will work with servers that do not support HEAD requests.

It uses cURL to make a request for the content with an HTTP range header asking for the first byte of the file.

If the server supports range requests (most media servers will) then it will receive the response with the size of the resource.

If the server does not response with a byte range, it will look for a content-length header to determine the length.

If the size is found in a range or content-length header, the transfer is aborted. If the size is not found and the function starts reading the response body, the transfer is aborted.

This could be a supplementary approach if a HEAD request results in a 405 method not supported response.

/**
 * Try to determine the size of a remote file by making an HTTP request for
 * a byte range, or look for the content-length header in the response.
 * The function aborts the transfer as soon as the size is found, or if no
 * length headers are returned, it aborts the transfer.
 *
 * @return int|null null if size could not be determined, or length of content
 */
function getRemoteFileSize($url)
{
    $ch = curl_init($url);

    $headers = array(
        'Range: bytes=0-1',
        'Connection: close',
    );

    $in_headers = true;
    $size       = null;

    curl_setopt($ch, CURLOPT_HEADER, 1);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($ch, CURLOPT_USERAGENT, 'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/46.0.2450.0 Iron/46.0.2450.0');
    curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
    curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0);
    curl_setopt($ch, CURLOPT_VERBOSE, 0); // set to 1 to debug
    curl_setopt($ch, CURLOPT_STDERR, fopen('php://output', 'r'));

    curl_setopt($ch, CURLOPT_HEADERFUNCTION, function($curl, $line) use (&$in_headers, &$size) {
        $length = strlen($line);

        if (trim($line) == '') {
            $in_headers = false;
        }

        list($header, $content) = explode(':', $line, 2);
        $header = strtolower(trim($header));

        if ($header == 'content-range') {
            // found a content-range header
            list($rng, $s) = explode('/', $content, 2);
            $size = (int)$s;
            return 0; // aborts transfer
        } else if ($header == 'content-length' && 206 != curl_getinfo($curl, CURLINFO_HTTP_CODE)) {
            // found content-length header and this is not a 206 Partial Content response (range response)
            $size = (int)$content;
            return 0;
        } else {
            // continue
            return $length;
        }
    });

    curl_setopt($ch, CURLOPT_WRITEFUNCTION, function($curl, $data) use ($in_headers) {
        if (!$in_headers) {
            // shouldn't be here unless we couldn't determine file size
            // abort transfer
            return 0;
        }

        // write function is also called when reading headers
        return strlen($data);
    });

    $result = curl_exec($ch);
    $info   = curl_getinfo($ch);

    return $size;
}

Usage:

$size = getRemoteFileSize('http://example.com/video.mp4');
if ($size === null) {
    echo "Could not determine file size from headers.";
} else {
    echo "File size is {$size} bytes.";
}

Answer 3

The simplest and most efficient implementation:

function remote_filesize($url, $fallback_to_download = false)
{
    static $regex = '/^Content-Length: *+\K\d++$/im';
    if (!$fp = @fopen($url, 'rb')) {
        return false;
    }
    if (isset($http_response_header) && preg_match($regex, implode("\n", $http_response_header), $matches)) {
        return (int)$matches[0];
    }
    if (!$fallback_to_download) {
        return false;
    }
    return strlen(stream_get_contents($fp));
}

Answer 4

Found something about this here:

Here's the best way (that I've found) to get the size of a remote file. Note that HEAD requests don't get the actual body of the request, they just retrieve the headers. So making a HEAD request to a resource that is 100MB will take the same amount of time as a HEAD request to a resource that is 1KB.

<?php
/**
 * Returns the size of a file without downloading it, or -1 if the file
 * size could not be determined.
 *
 * @param $url - The location of the remote file to download. Cannot
 * be null or empty.
 *
 * @return The size of the file referenced by $url, or -1 if the size
 * could not be determined.
 */
function curl_get_file_size( $url ) {
  // Assume failure.
  $result = -1;

  $curl = curl_init( $url );

  // Issue a HEAD request and follow any redirects.
  curl_setopt( $curl, CURLOPT_NOBODY, true );
  curl_setopt( $curl, CURLOPT_HEADER, true );
  curl_setopt( $curl, CURLOPT_RETURNTRANSFER, true );
  curl_setopt( $curl, CURLOPT_FOLLOWLOCATION, true );
  curl_setopt( $curl, CURLOPT_USERAGENT, get_user_agent_string() );

  $data = curl_exec( $curl );
  curl_close( $curl );

  if( $data ) {
    $content_length = "unknown";
    $status = "unknown";

    if( preg_match( "/^HTTP\/1\.[01] (\d\d\d)/", $data, $matches ) ) {
      $status = (int)$matches[1];
    }

    if( preg_match( "/Content-Length: (\d+)/", $data, $matches ) ) {
      $content_length = (int)$matches[1];
    }

    // http://en.wikipedia.org/wiki/List_of_HTTP_status_codes
    if( $status == 200 || ($status > 300 && $status <= 308) ) {
      $result = $content_length;
    }
  }

  return $result;
}
?>

Usage:

$file_size = curl_get_file_size( "http://stackoverflow.com/questions/2602612/php-remote-file-size-without-downloading-file" );

Answer 5

Php function get_headers() works for me to check the content-length as

$headers = get_headers('http://example.com/image.jpg', 1);
$filesize = $headers['Content-Length'];

For More Detail : PHP Function get_headers()

Answer 6

Try this code

function retrieve_remote_file_size($url){
     $ch = curl_init($url);

     curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
     curl_setopt($ch, CURLOPT_HEADER, TRUE);
     curl_setopt($ch, CURLOPT_NOBODY, TRUE);

     $data = curl_exec($ch);
     $size = curl_getinfo($ch, CURLINFO_CONTENT_LENGTH_DOWNLOAD);

     curl_close($ch);
     return $size;
}