How is Magento\Framework\View\Page\Config\Reader\Head::setMetadata() implemented and used?

dmitry_fedyuk · May 8, 2017, 11:13pm

Context: how is Magento\Framework\View\Page\Config::setMetadata() implemented and used?

Implementation

magento/magento2/blob/2.1.6/lib/internal/Magento/Framework/View/Page/Config/Reader/Head.php#L126-L142


/**
 * Set metadata
 *
 * @param \Magento\Framework\View\Page\Config\Structure $pageConfigStructure
 * @param \Magento\Framework\View\Layout\Element $node
 * @return void
 */
private function setMetadata($pageConfigStructure, $node)
{
    if (!$node->getAttribute('name') && $node->getAttribute('property')) {
        $metadataName = $node->getAttribute('property');
    } else {
        $metadataName = $node->getAttribute('name');
    }


    $pageConfigStructure->setMetaData($metadataName, $node->getAttribute('content'));
}

Details: how is Magento\Framework\View\Page\Config::setMetadata() implemented and used?

Intention

It is used to add some HTML <meta> tags to the current page via a layout.xml file.

How is it called?

Step 1. Magento\Framework\View\Layout::build()

Step 2. Magento\Framework\View\Layout\Builder::build()

Step 3. Magento\Framework\View\Page\Builder::generateLayoutBlocks()

Step 4. Magento\Framework\View\Layout\Builder::generateLayoutBlocks()

github.com

magento/magento2/blob/2.1.6/lib/internal/Magento/Framework/View/Layout/Builder.php#L128-L129


/* generate blocks from xml layout */
$this->layout->generateElements();

Step 5. Magento\Framework\View\Layout::generateElements()

github.com

magento/magento2/blob/2.1.6/lib/internal/Magento/Framework/View/Layout.php#L326-L328


\Magento\Framework\Profiler::start('generate_elements');
$this->generatorPool->process($this->getReaderContext(), $generatorContext);
\Magento\Framework\Profiler::stop('generate_elements');

Step 6. Magento\Framework\View\Layout\ReaderPool::interpret()

github.com

magento/magento2/blob/2.1.6/lib/internal/Magento/Framework/View/Layout/ReaderPool.php#L103-L105


/** @var $reader Layout\ReaderInterface */
$reader = $this->nodeReaders[$nodeName];
$reader->interpret($readerContext, $node, $element);

Step 7. Magento\Framework\View\Page\Config\Reader\Head::interpret()

github.com

magento/magento2/blob/2.1.6/lib/internal/Magento/Framework/View/Page/Config/Reader/Head.php#L92-L94


case self::HEAD_META:
    $this->setMetadata($pageConfigStructure, $node);
    break;

Step 8. Magento\Framework\View\Page\Config\Reader\Head::setMetadata()

github.com

magento/magento2/blob/2.1.6/lib/internal/Magento/Framework/View/Page/Config/Reader/Head.php#L126-L142


/**
 * Set metadata
 *
 * @param \Magento\Framework\View\Page\Config\Structure $pageConfigStructure
 * @param \Magento\Framework\View\Layout\Element $node
 * @return void
 */
private function setMetadata($pageConfigStructure, $node)
{
    if (!$node->getAttribute('name') && $node->getAttribute('property')) {
        $metadataName = $node->getAttribute('property');
    } else {
        $metadataName = $node->getAttribute('name');
    }


    $pageConfigStructure->setMetaData($metadataName, $node->getAttribute('content'));
}

dmitry_fedyuk · May 8, 2017, 11:42pm

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