/**
* Generate a short URL for an object if none exists
*
* @param IHasShortUrl $object
* @param bool $b_regenerate
* @return ShortUrl
*/
public function EnsureShortUrl(IHasShortUrl $object, $b_regenerate = false)
{
if (!$object->GetShortUrl() or $b_regenerate) {
$i_preference = 0;
$current_url = $object->GetShortUrl();
$object->SetShortUrl('');
do {
$i_preference++;
$object->SetShortUrl($object->SuggestShortUrl($i_preference));
if ($b_regenerate and $object->GetShortUrl() == $current_url) {
return;
}
# if regenerating, it's ok to keep the current URL if it's still appropriate
} while ($this->IsUrlTaken($object->GetShortUrl()));
}
# Now add the new version, but if this is a new item there's a problem.
# This method is run before adding the new item to the database, so that we
# can write the item's short URL to the database at the same time as the
# rest of the item. But that means the item doesn't have an id yet, and
# generally we want to use the id. So, return the ShortUrl object so that it
# can be updated after the item has been inserted into the database.
$short_url = new ShortUrl($object->GetShortUrl());
$short_url->SetFormat($object->GetShortUrlFormat());
# Use instance, not static, method so object has a chance to customise format
$short_url->SetParameterValuesFromObject($object);
return $short_url;
}