How to create Resources (documents) from the front end (with a form)?

$doc = $modx->getObject('modResource',array('id'=>$hook->getValue('resource_id')));
 
if (empty($doc)){
    $doc = $modx->newObject('modResource');
    $doc->set('createdby', $modx->user->get('id'));
}
else{
    $doc->set('editedby', $modx->user->get('id'));
}
 
$allFormFields = $hook->getValues(); 
foreach ($allFormFields as $field=>$value)
{
 
   if ($field !== 'spam' && $field !== 'resource_id'){
         $doc->set($field, $value);
    }

   //we need to parse the title into the alias
   if($field == 'pagetitle'){
      //replace spaces with -
      $alias = preg_replace('/[\' \']/' , '-' , $value);

      //remove non alpha and a common injection string 
      $alias = preg_replace('/[^a-z0-9\.\x0B\-]/i' , '' , $alias);

                                   //this is the standard revo regexp
                                   // \0\x0B\t\n\r\f\a&=+%#<>"~:`@\?\[\]\{\}\|\^'\
   }
}
 // now set the alias
 $doc->set('alias', $alias);
 
$doc->set('template', '1');
$doc->save();
 
foreach ($allFormFields as $field=>$value)
{
    if ($tv = $modx->getObject('modTemplateVar', array ('name'=>$field)))
    {
        /* handles checkboxes & multiple selects elements */
        if (is_array($value)) {
            $featureInsert = array();
            while (list($featureValue, $featureItem) = each($value)) {
                $featureInsert[count($featureInsert)] = $featureItem;
            }
            $value = implode('||',$featureInsert);
        }   
        $tv->setValue($doc->get('id'), $value);
        $tv->save();
    }
}
 
$url = $modx->makeUrl(84);
$modx->cacheManager->refresh(); // suggested by gallenkamp
$modx->sendRedirect($url);

$modx->cacheManager->refresh();

<option value="blue" [[!+fi.color:FormItIsSelected=`blue`]] >Blue</option>

name="color[]"

$doc->set('template', '1');
$isnew = $doc->isNew();

if ($doc->save()) {
    if ($isnew) {
        $doc->set('alias', $doc->get('alias' . '-' . $doc->get('id')));
        $doc->save();
    }
}

$doc->set('template', '1');
$doc->save();