Transform that supplies default values for the src and alt attributes in img tags, as well as prevents the img tag from being removed because of a missing alt tag. This needs to be registered as both a pre and post attribute transform.
<?php
// must be called POST validation
/**
* Transform that supplies default values for the src and alt attributes
* in img tags, as well as prevents the img tag from being removed
* because of a missing alt tag. This needs to be registered as both
* a pre and post attribute transform.
*/
class HTMLPurifier_AttrTransform_ImgRequired extends HTMLPurifier_AttrTransform
{
/**
* @param array $attr
* @param HTMLPurifier_Config $config
* @param HTMLPurifier_Context $context
* @return array
*/
public function transform($attr, $config, $context)
{
$src = true;
if (!isset($attr['src'])) {
if ($config->get('Core.RemoveInvalidImg')) {
return $attr;
}
$attr['src'] = $config->get('Attr.DefaultInvalidImage');
$src = false;
}
if (!isset($attr['alt'])) {
if ($src) {
$alt = $config->get('Attr.DefaultImageAlt');
if ($alt === null) {
$attr['alt'] = basename($attr['src']);
} else {
$attr['alt'] = $alt;
}
} else {
$attr['alt'] = $config->get('Attr.DefaultInvalidImageAlt');
}
}
return $attr;
}
}
// vim: et sw=4 sts=4