mkdir -p /path_to_project/project_name
cd /path_to_project/project_name
mkdir -p vendor
cd vendor
git clone https://github.com/servandserv/happymeal.git
cp /happymeal/happymeal.ini /path_to_project/project_name

path_to_happymeal/happymeal xsd2php path_to_project/project_name/happymeal.ini

$obj = new \namespace\Object();
if($xmlstr = file_get_contents('file_path')) {
  $obj->fromXmlStr($xmlstr);
}

$obj = new \namespace\Object();
$obj->setProp1("prop1");
$obj->setProp2("prop2");
$xmlstr = $obj->toXmlStr();

use \com\servandserv\happymeal\ErrorsHandler;

$eh = new ErrorsHandler();
$obj = new \namespace\Object();
if($xmlstr = file_get_contents('file_path')) {
  $obj->fromXmlStr($xmlstr);
}
if( $errors = $obj->validateType( $eh ) ) {
    header( "Content-Type: application/xml" );
    print $errors->toXmlStr();
    exit;
}