AWS S3 Bucket MP4 Videos wrong mime-type

When copying files from one bucket to another, or uploading files to a bucket, some things may go wrong. For example, some keys representing folders in the file structure go missing – a solution to this problem is explained in a different post, see it here. Recently, another problem appeared: MP4 videos embedded as HMTM5 videos played in all browsers but Internet Explorer 9. In my case this happened, because S3 returned headers which did not contain “video/mp4” as mime-type but “application/octet-stream”. This obviously stopped IE 9 from playing the videos.

How to check the mime-type of a file in S3

If you run into this problem, you can easily find out, if the mime-type is set correctly in your bucket video file. The following example uses PHP with the PHP-SDK for AWS, but you can make this example work for any programming language and the respective SDK (the SDKs can be found here).

First of all, add a simple configuration array containing your credentials and the location of your bucket. Delete the v4 line, if your region does not support it. Save the file as “config.php”.

<?php
return array(
    'includes' => array('_aws'),
    'services' => array(
        'default_settings' => array(
            'params' => array(
                'key'    => 'YOUR_KEY',
                'secret' => 'YOUR_SECRET',
                'region' => 'eu-central-1',
                'signature'    => 'v4'
            )
        )
    )
);

The following PHP script requires the Amazon PHP SDK, you can see the “autoloader” in the “require” statement. It uses the configuration file we created in the previous step, be sure that the path to the file is correct. If the file resides in the same directory and the name is “config.php”, you may leave the line like it is.

Use the variable “$params” to define the name of your bucket and the path to the mp4 file you want to check. The “echo” at the end prints the result of getting the object. The PHP script looks like this:

<?php

require 'aws/aws-autoloader.php';
use Aws\Common\Aws;

$aws = Aws::factory('config.php');
$client = $aws->get('s3');

$params = array(
    'Bucket' => 'bucket_name',
    'Key' => 'user_upload/folder_one/folder_two/file_name.mp4'
);

echo '<pre>';
var_dump($client->getObject($params));
echo '</pre>';

When executing this script, you will get a result which looks like the following:

object(Guzzle\Service\Resource\Model)#89 (2) {
  ["structure":protected]=>
  NULL
  ["data":protected]=>
  array(22) {
    ["Body"]=>
    object(Guzzle\Http\EntityBody)#92 (6) {
      ["contentEncoding":protected]=>
      bool(false)
      ["rewindFunction":protected]=>
      NULL
      ["stream":protected]=>
      resource(7) of type (stream)
      ["size":protected]=>
      NULL
      ["cache":protected]=>
      array(9) {
        ["wrapper_type"]=>
        string(3) "PHP"
        ["stream_type"]=>
        string(4) "TEMP"
        ["mode"]=>
        string(3) "w+b"
        ["unread_bytes"]=>
        int(0)
        ["seekable"]=>
        bool(true)
        ["uri"]=>
        string(10) "php://temp"
        ["is_local"]=>
        bool(true)
        ["is_readable"]=>
        bool(true)
        ["is_writable"]=>
        bool(true)
      }
      ["customData":protected]=>
      array(1) {
        ["default"]=>
        bool(true)
      }
    }
    ["DeleteMarker"]=>
    bool(false)
    ["AcceptRanges"]=>
    string(5) "bytes"
    ["Expiration"]=>
    string(0) ""
    ["Restore"]=>
    string(0) ""
    ["LastModified"]=>
    string(29) "Mon, 01 Dec 2014 13:43:25 GMT"
    ["ContentLength"]=>
    string(8) "60209681"
    ["ETag"]=>
    string(34) ""531b21ac92269de9ca9b6459bccf62a0""
    ["MissingMeta"]=>
    string(0) ""
    ["VersionId"]=>
    string(4) "null"
    ["CacheControl"]=>
    string(0) ""
    ["ContentDisposition"]=>
    string(0) ""
    ["ContentEncoding"]=>
    string(0) ""
    ["ContentLanguage"]=>
    string(0) ""
    ["ContentType"]=>
    string(9) "video/mp4"
    ["Expires"]=>
    string(0) ""
    ["WebsiteRedirectLocation"]=>
    string(0) ""
    ["ServerSideEncryption"]=>
    string(0) ""
    ["SSECustomerAlgorithm"]=>
    string(0) ""
    ["SSECustomerKeyMD5"]=>
    string(0) ""
    ["SSEKMSKeyId"]=>
    string(0) ""
    ["RequestId"]=>
    string(16) "830D3203B2E744AC"
  }
}

Here you need to view the output of “ContentType” – if it is something else than “video/mp4”, the mime-type for the mp4 video is not set correctly. Since this seems to happen sometimes when moving buckets, or when using bulk upload for many mp4 files, I wrote a script which gets all mp4 videos, checks the “ContentType” and set its to “video/mp4” if it’s not already set. The script used looks like this:

<?php

require 'aws/aws-autoloader.php';
use Aws\Common\Aws;

ob_implicit_flush(true);
ob_end_flush();

$aws = Aws::factory('config.php');
$client = $aws->get('s3');

echo "starting to get objects";
echo "<br />";

$allObjects = AWSUtil::listObjectsHelper('pwwstage', $client);

$changedKeys = array();

foreach($allObjects as $object) {
    $paramsGet = array(
        'Bucket' => 'pwwstage',
        'Key' => $object['Key'],
    );

    if (AWSUtil::endsWith($object['Key'], ".mp4")) {
        $getResult = $client->getObject($paramsGet);
        $bodyContent = $getResult['Body'];

        echo "checking key " . $object['Key'];
        echo "<br />";

        if (($getResult['ContentType']) && ($getResult['ContentType'] != 'video/mp4')) {
            $paramsPut = array(
                'Bucket' => 'pwwstage',
                'Key' => $object['Key'],
                'ContentType' => 'video/mp4',
                'Body' => $bodyContent
            );

            echo "updating contenttype on " . $object['Key'];
            echo "<br />";

            $client->putObject($paramsPut);
            array_push($changedKeys, $object['Key']);
        }
    }

}

foreach($changedKeys as $changedKey) {
    echo $changedKey;
    echo "<br />";
}

echo "done";

class AWSUtil
{
    /**
     * Helper function to receive all keys from an object, not only up to 1000
     * This works recursively
     *
     * @param string $bucket
     * * @param array $s3client
     * @param array $responseArray
     * @param string $marker
     * @return array
     */
    public static function listObjectsHelper($bucket, $s3client, $responseArray = array(), $marker = NULL)
    {

        // first call: marker is not set
        if (!$marker) {
            $responseTemp = $s3client->listObjects(array(
                'Bucket' => $bucket,
            ))->toArray();
        } else {
            $responseTemp = $s3client->listObjects(array(
                'Bucket' => $bucket,
                'Marker' => $marker
            ))->toArray();
        }

        foreach ($responseTemp['Contents'] as $res) {
            array_push($responseArray, $res);
        }

        if (count($responseTemp['Contents']) === 1000) {
            $marker = $responseTemp['Contents'][999]['Key'];
            return AWSUtil::listObjectsHelper($bucket, $s3client, $responseArray, $marker);
        } else {
            return $responseArray;
        }
    }

    public static function endsWith($haystack, $needle)
    {
        $length = strlen($needle);
        if ($length == 0) {
            return true;
        }

        return (substr($haystack, -$length) === $needle);
    }
}

Leave a Reply