how to disable cache for cms block?

Question

unfortunately in this situation I do not have $this->getChildHtml to assign false to it and then change my xml file for disabling cache I have this block in view.phtml:

    <?php echo $this->getCmsBlockHtml() ?>

and the function is in view.php as follow:

public function getCmsBlockHtml()
{
    if (!$this->getData('cms_block_html')) {
        $html = $this->getLayout()->createBlock('cms/block')
            ->setBlockId($this->getCurrentCategory()->getLandingPage())
            ->toHtml();
        $this->setData('cms_block_html', $html);
    }
    return $this->getData('cms_block_html');
}

any ideas on how to disable the cache here? my page is in category folder when displaying the products

Update:with help of Denis I understood that (for some pages) when I have something in constructor if the cache is enabled the constructor will not be called! and so I think that's the reason why setting the cache life time doesn't work there

Answer 1

To disable Block Html Cache you should set cacheLifeTime to null. You can see more details in Mage_Core_Block_Abstract::_loadCache()

protected function _loadCache()
{
    if (is_null($this->getCacheLifetime()) || !$this->_getApp()->useCache(self::CACHE_GROUP)) {
        return false;
    }
    ...
}

Answer 2

In Mage_*_Block_Template classes you can control the cache through the constructor

protected function _construct()
{
    $this->addData(array(
                    'cache_lifetime'   => 86400, //1 day
                    'cache_tags'   => array(Mage_Catalog_Model_Product::CACHE_TAG), //for adding in product detail page
                    'cache_key'   => 'some-identifier' //optional, but should be unique if used
    ));
}

In definition createBlock function, we have three parameters:

public function createBlock ($type, $name = '', $attributes = array()) 

You can then use the parameters to pass attributes of the data cache, like this:

$html = $this->getLayout()->createBlock('cms/block','',
    array(
        'cache_lifetime' => false,
        'cache_tags' => array(Mage_Catalog_Model_Product::CACHE_TAG)
    ))
    ->setBlockId($this->getCurrentCategory()->getLandingPage())
    ->toHtml();