Initial commit

2018-04-02 08:07:38 +02:00
commit 7330c1ed3e
2054 changed files with 405203 additions and 0 deletions
--- a/typo3conf/ext/vhs/Classes/ViewHelpers/Asset/PrefetchViewHelper.php
+++ b/typo3conf/ext/vhs/Classes/ViewHelpers/Asset/PrefetchViewHelper.php
@@ -0,0 +1,97 @@
+<?php
+namespace FluidTYPO3\Vhs\ViewHelpers\Asset;
+
+/*
+ * This file is part of the FluidTYPO3/Vhs project under GPLv2 or later.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.md file that was distributed with this source code.
+ */
+
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * ### Asset DNS Prefetching ViewHelper
+ *
+ * Enables the special `<link rel="dns-prefetch" />` tag
+ * which instructs the browser to start prefetching DNS
+ * records for every domain listed in the `domains` attribute
+ * of this ViewHelper. Prefetching starts as soon as the browser
+ * becomes aware of the tag - to optimise even further, you may
+ * wish to control the output buffer's size to deliver your site
+ * HTML in chunks, the first chunk being the one containing this
+ * ViewHelper.
+ *
+ * Note that the web server daemon may send headers which prevent
+ * this prefetching and that these headers can be added in many
+ * ways. If prefetching does not work, you will need to inspect
+ * the HTTP headers returned from the actual environment. Or you
+ * may prefer to simply add `force="TRUE"` to this tag - but
+ * beware that this will affect the entire document's behaviour,
+ * not just for this particular set of domain prefetches. Once
+ * force-enabled this setting cannot be disabled (unless done so
+ * by manually adding an additional meta header tag as examplified
+ * by the `build()` method.
+ *
+ * ### Example usage:
+ *
+ *     <v:asset.prefetch domains="fedext.net,ajax.google.com" />
+ *
+ * See: https://developer.mozilla.org/en-US/docs/Controlling_DNS_prefetching
+ *
+ * @package Vhs
+ * @subpackage ViewHelpers\Asset
+ */
+class PrefetchViewHelper extends AbstractAssetViewHelper {
+
+	/**
+	 * @var string
+	 */
+	protected $type = 'link';
+
+	/**
+	 * @return void
+	 */
+	public function initializeArguments() {
+		parent::initializeArguments();
+		$this->registerArgument('domains', 'mixed', 'Domain DNS names to prefetch. By default will add all sys_domain record DNS names', TRUE);
+		$this->registerArgument('protocol', 'string', 'Optional value of protocol as inserted in the resulting HREF value. If you experience problems with a non-protocol link, try enforcing http/https here', FALSE, NULL);
+		$this->registerArgument('protocolSeparator', 'string', 'If you do not enforce a particular protocol and wish to remove the double slashes from the hostname (your browser may not understand this!), set this attribute to an empty value (not-zero)', FALSE, '//');
+		$this->registerArgument('force', 'boolean', 'If TRUE, adds an additional meta header tag which forces prefetching to be enabled even if otherwise requested by the http daemon', FALSE, FALSE);
+	}
+
+
+	/**
+	 * @return void
+	 */
+	public function render() {
+		$this->arguments['standalone'] = TRUE;
+		$this->arguments['allowMoveToFooter'] = FALSE;
+		$this->tagBuilder->forceClosingTag(FALSE);
+		$this->tagBuilder->addAttribute('rel', 'dns-prefetch');
+		$this->tagBuilder->addAttribute('href', '');
+		$this->tagBuilder->setTagName('link');
+		$this->finalize();
+	}
+
+	/**
+	 * @return string
+	 */
+	public function build() {
+		$domains = $this->arguments['domains'];
+		if (FALSE === is_array($domains)) {
+			$domains = GeneralUtility::trimExplode(',', $domains, TRUE);
+		}
+		$headerCode = '';
+		if (TRUE === (boolean) $this->arguments['force']) {
+			$headerCode .= '<meta http-equiv="x-dns-prefetch-control" content="off">' . LF;
+		}
+		foreach ($domains as $domain) {
+			$this->tagBuilder->removeAttribute('href');
+			$this->tagBuilder->addAttribute('href', $this->arguments['protocol'] . $this->arguments['protocolSeparator'] . $domain);
+			$headerCode .= $this->tagBuilder->render() . LF;
+		}
+		return $headerCode;
+	}
+
+}