POST operation adds an object to a specified bucket using HTML forms. POST is an alternate
* form of PUT that enables browser-based uploads as a way of putting objects in buckets.
* Parameters that are passed to PUT via HTTP headers are instead passed as form fields to
* POST in the multipart/form-data encoded message body. You must have
* WRITE access on a bucket to add an object to it. Amazon S3 never stores partial objects: if
* you receive a successful response, you can be confident the entire object was stored.
*
* @param string $bucket (Required) The name of the bucket to use.
* @param string|integer $expires (Optional) The point in time when the upload form field should expire. The default value is +1 hour.
* @param array $opt (Optional) An associative array of parameters that can have the following keys:
* acl - string - Optional - The access control setting to apply to the uploaded file. Accepts any of the following constants: [Allowed values: AmazonS3::ACL_PRIVATE, AmazonS3::ACL_PUBLIC, AmazonS3::ACL_OPEN, AmazonS3::ACL_AUTH_READ, AmazonS3::ACL_OWNER_READ, AmazonS3::ACL_OWNER_FULL_CONTROL].Cache-Control - string - Optional - The Cache-Control HTTP header value to apply to the uploaded file. To use a starts-with comparison instead of an equals comparison, prefix the value with a ^ (carat) character.Content-Disposition - string - Optional - The Content-Disposition HTTP header value to apply to the uploaded file. To use a starts-with comparison instead of an equals comparison, prefix the value with a ^ (carat) character.Content-Encoding - string - Optional - The Content-Encoding HTTP header value to apply to the uploaded file. To use a starts-with comparison instead of an equals comparison, prefix the value with a ^ (carat) character.Content-Type - string - Optional - The Content-Type HTTP header value to apply to the uploaded file. The default value is application/octet-stream. To use a starts-with comparison instead of an equals comparison, prefix the value with a ^ (carat) character.Expires - string - Optional - The Expires HTTP header value to apply to the uploaded file. To use a starts-with comparison instead of an equals comparison, prefix the value with a ^ (carat) character.key - string - Optional - The location where the file should be uploaded to. The default value is ${filename}.success_action_redirect - string - Optional - The URI for Amazon S3 to redirect to upon successful upload.success_action_status - integer - Optional - The status code for Amazon S3 to return upon successful upload.x-amz-storage-class - string - Optional - The storage setting to apply to the object. [Allowed values: AmazonS3::STORAGE_STANDARD, AmazonS3::STORAGE_REDUCED]. The default value is AmazonS3::STORAGE_STANDARD.- x-amz-meta-*
*
* @return array An array of fields that can be converted into markup.
* @link http://docs.amazonwebservices.com/AmazonS3/latest/API/RESTObjectPOST.html POST Object
*/
public function generate_upload_parameters($bucket, $expires = '+1 hour', $opt = null)
{
if (!$opt) $opt = array();
// Policy document
$policy = array(
'conditions' => array(
array('bucket' => $bucket),
)
);
// Basic form
$form = array();
$form['form'] = array(
'action' => $bucket . '.s3.amazonaws.com',
'method' => 'POST',
'enctype' => 'multipart/form-data'
);
// Inputs
$form['inputs'] = array(
'AWSAccessKeyId' => $this->key
);
// Expires
if ($expires)
{
if (is_numeric($expires))
{
$expires = gmdate('j M Y, g:i a Z', (integer) $expires);
}
$expires = $this->util->convert_date_to_iso8601($expires);
$policy['expiration'] = (string) $expires;
}
// Default values
if (!isset($opt['key']))
{
$opt['key'] = '${filename}';
}
// Success Action Status
if (isset($opt['success_action_status']) && !empty($opt['success_action_status']))
{
$form['inputs']['success_action_status'] = (string) $opt['success_action_status'];
$policy['conditions'][] = array(
'success_action_status' => (string) $opt['success_action_status']
);
unset($opt['success_action_status']);
}
// Other parameters
foreach ($opt as $param_key => $param_value)
{
if ($param_value[0] === '^')
{
$form['inputs'][$param_key] = substr((string) $param_value, 1);
$param_value = preg_replace('/\$\{(\w*)\}/', '', (string) $param_value);
$policy['conditions'][] = array('starts-with', '$' . $param_key, (substr((string) $param_value, 1) ? substr((string) $param_value, 1) : ''));
}
else
{
$form['inputs'][$param_key] = (string) $param_value;
$policy['conditions'][] = array(
$param_key => (string) $param_value
);
}
}
// Add policy
$json_policy = json_encode($policy);
$json_policy_b64 = base64_encode($json_policy);
$form['inputs']['policy'] = $json_policy_b64;
$form['metadata']['json_policy'] = $json_policy;
// Add signature
$form['inputs']['signature'] = base64_encode(hash_hmac('sha1', $json_policy_b64, $this->secret_key, true));
return $form;
}
/*%******************************************************************************************%*/
// HELPERS
/**
* Returns the protocol of the web page that this script is currently running on. This method only works
* correctly when run from a publicly-accessible web page.
*/
public static function protocol()
{
return (isset($_SERVER['HTTPS']) && strtolower($_SERVER['HTTPS']) === 'on') ? 'https://' : 'http://';
}
/**
* Returns the domain (and port) of the web page that this script is currently running on. This method
* only works correctly when run from a publicly-accessible web page.
*/
public static function domain()
{
if (isset($_SERVER['SERVER_NAME']) && isset($_SERVER['SERVER_PORT']))
{
return $_SERVER['SERVER_NAME'] . ((integer) $_SERVER['SERVER_PORT'] === 80 ? '' : ':' . $_SERVER['SERVER_PORT']);
}
return null;
}
/**
* Returns the URI of the web page that this script is currently running on. This method only works
* correctly when run from a publicly-accessible web page.
*/
public static function current_uri()
{
if (isset($_SERVER['REQUEST_URI']))
{
$uri = self::protocol();
$uri .= self::domain();
$uri .= $_SERVER['REQUEST_URI'];
return $uri;
}
return null;
}
}