Question

I’m working on a CakePHP 1.3 project in a LAMP environment in which we store a number of videos outside of /app/webroot/ and serve them up using CakePHP’s Media Views (we do this as we don’t want the files directly accessible). However, I’m having trouble serving these videos up to iOS devices (e.g., iPhone, iPad) via Media Views.

I can place my test video somewhere within /app/webroot/ and access it directly on an iOS device and playback works as expected, so I’m pretty sure it’s not a MOOV problem or another encoding issue with the video itself. As far as I can tell, it’s got something to do with CakePHP’s handling (or lack thereof) of byte-range requests that iOS devices use when loading video.

I found one other Stack Overflow ticket that has unfortunately gone unanswered, but details a similar problem. Looking at the /cake/libs/view/media.php class file, there is an if statement within the render() method that is cued on a check for a $_SERVER['HTTP_RANGE'] value; but as far as I can tell in testing, this value is never being set (at least not when CakePHP looks for it). The offsite solution linked in the aforementioned ticket doesn’t solve my problem as it too relies on a check of this value, which I’ve verified is not being found when checked for either in the Media View class itself, or in the controller that’s setting up said view.

So, has anyone had any luck or experience serving videos up to iOS devices using CakePHP Media Views? Thanks in advance!

Answer 1

After no hits on the various questions I posted around the web, we took another crack at this and were able to figure it out.

Turns out it’s an issue in the Media.php class file (/cake/libs/view/media.php) with its expectation of the HTTP_RANGE header value, and how it was formatting the subsequent header. First, here’s the original relevant code snippet:

$httpRange = env('HTTP_RANGE');
if (isset($httpRange)) {
    list($toss, $range) = explode('=', $httpRange);

    $size = $fileSize - 1;
    $length = $fileSize - $range;

    $this->_header(array(
        'HTTP/1.1 206 Partial Content',
        'Content-Length: ' . $length,
        'Content-Range: bytes ' . $range . $size . '/' . $fileSize));

    fseek($handle, $range);
}

Note the list() call, which populates a $range value that is then used as if it were numeric. However, after debugging the header calls further, we noticed that the HTTP_RANGE value is actually given as Range: bytes=0-1000 where the given numeric range depends on the request. We made the following changes (and set the download boolean to true on the Media View call), and voila, working video on iOS devices.

$httpRange = env('HTTP_RANGE');
if (isset($httpRange)) {
    $start = 0; //start byte
    $end = $fileSize - 1; //end byte
    $length = $fileSize; //content length

    $c_start = $start; //default value
    $c_end = $end; //default value
    list($toss, $range) = explode('=', $httpRange); //extract range

    //grab range value(s)
    if ($range[0] == '-') {
        $c_start = $fileSize - substr($range, 1);
    } else {
        $range = explode('-', $range);
        $c_start = $range[0];
        $c_end = (isset($range[1]) && is_numeric($range[1])) ? $range[1] : $fileSize;
    }

    //validate end byte
    $c_end = ($c_end > $end) ? $end : $c_end;

    //set new values
    $start = $c_start;
    $end = $c_end;
    $length = $end - $start + 1;

    $this->_header(array(
        'HTTP/1.1 206 Partial Content',
        'Content-Length: ' . $length,
        'Content-Range: bytes ' . $start . '-' . $end . '/' . $fileSize));
    fseek($handle, $start);
}

Note that this incorporates much of the logic from Appendix A of this article, which handles a variety of cases. (Initially we eschewed much of this logic, and while playback worked fine, once the end of the file was reached on an iOS device it seemed to be acting a little wonky.)