Add PreloadHeroImage Optimizer transformer

lib/common/src/Amp.php

@@ -2,6 +2,7 @@
 
 namespace AmpProject;
 
+use AmpProject\Dom\Document;
 use DOMElement;
 use DOMNode;
 
@@ -249,6 +250,56 @@ public static function isCustomElement(DOMNode $node)
         return $node instanceof DOMElement && strpos($node->tagName, Extension::PREFIX) === 0;
     }
 
+    /**
+     * Check whether the given document is an AMP story.
+     *
+     * @param Document $document Document of the page to check within.
+     * @return bool Whether the provided document is an AMP story.
+     */
+    public static function isAmpStory(Document $document)
+    {
+        foreach ($document->head->childNodes as $node) {
+            if (
+                $node instanceof DOMElement
+                &&
+                $node->tagName === Tag::SCRIPT
+                &&
+                $node->getAttribute(Attribute::CUSTOM_ELEMENT) === Extension::STORY
+            ) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * Check whether a given node is an AMP template.
+     *
+     * @param DOMNode $node Node to check.
+     * @return bool Whether the node is an AMP template.
+     */
+    public static function isTemplate(DOMNode $node)
+    {
+        if (! $node instanceof DOMElement) {
+            return false;
+        }
+
+        if ($node->tagName === Tag::TEMPLATE) {
+            return true;
+        }
+
+        if (
+            $node->tagName === Tag::SCRIPT
+            && $node->hasAttribute(Attribute::TEMPLATE)
+            && $node->getAttribute(Attribute::TEMPLATE) === Extension::MUSTACHE
+        ) {
+            return true;
+        }
+
+        return false;
+    }
+
     /**
      * Check whether a given node is an async <script> element.
      *
@@ -273,4 +324,20 @@ private static function isAsyncScript(DOMNode $node)
 
         return true;
     }
+
+    /**
+     * Check whether a given node is an AMP iframe.
+     *
+     * @param DOMNode $node Node to check.
+     * @return bool Whether the node is an AMP iframe.
+     */
+    public static function isAmpIframe(DOMNode $node)
+    {
+        if (! $node instanceof DOMElement) {
+            return false;
+        }
+
+        return $node->tagName === Extension::IFRAME
+               || $node->tagName === Extension::VIDEO_IFRAME;
+    }
 }

lib/common/src/Attribute.php

@@ -29,6 +29,7 @@ interface Attribute
     const AMP_SCRIPT_SRC        = 'amp-script-src';
     const ARIA_HIDDEN           = 'aria-hidden';
     const ASYNC                 = 'async';
+    const ATTRIBUTION           = 'attribution';
     const AUTOPLAY              = 'autoplay';
     const CHARSET               = 'charset';
     const CLASS_                = 'class'; // Underscore needed because 'class' is a PHP keyword.
@@ -43,6 +44,7 @@ interface Attribute
     const HOST_SERVICE          = 'host-service';
     const HREF                  = 'href';
     const HTTP_EQUIV            = 'http-equiv';
+    const I_AMPHTML_SSR         = 'i-amphtml-ssr';
     const I_AMPHTML_VERSION     = 'i-amphtml-version';
     const ID                    = 'id';
     const IMPORTANCE            = 'importance';
@@ -55,8 +57,12 @@ interface Attribute
     const NAME                  = 'name';
     const NOLOADING             = 'noloading';
     const OBJECT_FIT            = 'object-fit';
+    const OBJECT_POSITION       = 'object-position';
     const ON                    = 'on';
+    const PLACEHOLDER           = 'placeholder';
+    const POSTER                = 'poster';
     const PROFILE               = 'profile';
+    const REFERRERPOLICY        = 'referrerpolicy';
     const REL                   = 'rel';
     const ROLE                  = 'role';
     const SRCSET                = 'srcset';
@@ -93,4 +99,6 @@ interface Attribute
     const REL_PRELOAD      = 'preload';
     const REL_PRERENDER    = 'prerender';
     const REL_STYLESHEET   = 'stylesheet';
+
+    const DATA_HERO = 'data-hero';
 }

lib/common/src/Dom/Document.php

@@ -19,11 +19,12 @@
  *
  * Abstract away some of the difficulties of working with PHP's DOMDocument.
  *
- * @property DOMXPath    $xpath       XPath query object for this document.
- * @property DOMElement  $html        The document's <html> element.
- * @property DOMElement  $head        The document's <head> element.
- * @property DOMElement  $body        The document's <body> element.
- * @property DOMNodeList $ampElements The document's <amp-*> elements.
+ * @property DOMXPath        $xpath       XPath query object for this document.
+ * @property DOMElement      $html        The document's <html> element.
+ * @property DOMElement      $head        The document's <head> element.
+ * @property DOMElement      $body        The document's <body> element.
+ * @property DOMElement|null $viewport    The document's viewport meta element.
+ * @property DOMNodeList     $ampElements The document's <amp-*> elements.
  *
  * @package ampproject/common
  */
@@ -1609,6 +1610,18 @@ public function __get($name)
                     $this->body = $this->getElementsByTagName(Tag::BODY)->item(0);
                 }
                 return $this->body;
+            case 'viewport':
+                // TODO: Can this be cached in an instance property as well?
+                for ($node = $this->head->firstChild; $node !== null; $node = $node->nextSibling) {
+                    if (
+                        $node instanceof DOMElement
+                        && $node->tagName === 'meta'
+                        && $node->getAttribute('name') === 'viewport'
+                    ) {
+                        return $node;
+                    }
+                }
+                return null;
             case 'ampElements':
                 $this->ampElements = $this->xpath->query(".//*[ starts-with( name(), 'amp-' ) ]", $this->body)
                     ?: new DOMNodeList();

lib/common/src/Extension.php

@@ -16,11 +16,14 @@ interface Extension
     const DYNAMIC_CSS_CLASSES = 'amp-dynamic-css-classes';
     const EXPERIMENT          = 'amp-experiment';
     const GEO                 = 'amp-geo';
+    const IFRAME              = 'amp-iframe';
+    const IMAGE               = 'amp-img';
     const MUSTACHE            = 'amp-mustache';
     const PIXEL               = 'amp-pixel';
     const SOCIAL_SHARE        = 'amp-social-share';
     const STORY               = 'amp-story';
     const VIDEO               = 'amp-video';
+    const VIDEO_IFRAME        = 'amp-video-iframe';
     const YOUTUBE             = 'amp-youtube';
 
     /**

lib/common/src/Tag.php

@@ -18,6 +18,7 @@ interface Tag
     const BODY       = 'body';
     const BR         = 'br';
     const COL        = 'col';
+    const DIV        = 'div';
     const EMBED      = 'embed';
     const FIGCAPTION = 'figcaption';
     const FIGURE     = 'figure';

lib/common/src/Url.php

@@ -0,0 +1,71 @@
+<?php
+
+namespace AmpProject;
+
+/**
+ * Helper class to work with URLs.
+ *
+ * @package ampproject/common
+ */
+final class Url
+{
+
+    /**
+     * Default URL parts to use when constructing an absolute URL out of a relative one.
+     *
+     * @var string[]
+     */
+    const URL_DEFAULT_PARTS = [
+        'scheme'   => 'https',
+        'host'     => 'example.com',
+        'port'     => '',
+        'user'     => '',
+        'pass'     => '',
+        'path'     => '',
+        'query'    => '',
+        'fragment' => '',
+    ];
+
+    /**
+     * Check whether a given src string is a valid image source URL.
+     *
+     * @param string $src Src string to validate.
+     * @return bool Whether the src string is a valid image source URL.
+     */
+    public static function isValidImageSrc($src)
+    {
+        list($scheme, $host, $port, $user, $pass, $path, $query, $fragment) = array_values(
+            array_merge(
+                self::URL_DEFAULT_PARTS,
+                (array)parse_url($src)
+            )
+        );
+
+        if ($scheme === 'data') {
+            return false;
+        }
+
+        $userpass = $user;
+
+        if (! empty($pass)) {
+            $userpass = "{$user}:{$pass}";
+        }
+
+        if (! empty($userpass)) {
+            $userpass .= '@';
+        }
+
+        $url = sprintf(
+            '%s://%s%s%s/%s%s%s',
+            $scheme,
+            $host,
+            $userpass,
+            empty($port) ? '' : ":{$port}",
+            ltrim($path, '/'),
+            empty($query) ? '' : "?{$query}",
+            empty($fragment) ? '' : "#{$fragment}"
+        );
+
+        return (bool)filter_var($url, FILTER_VALIDATE_URL);
+    }
+}

lib/common/tests/AmpTest.php

@@ -205,6 +205,83 @@ public function testIsExtension(DOMNode $node, $_, $expected)
         $this->assertEquals($expected, Amp::isExtension($node));
     }
 
+    /**
+     * Provide data for the testIsAmpStory() method.
+     *
+     * @return array[] Array
+     */
+    public function dataIsAmpStory()
+    {
+        $domAmpStoryCustomElement = Document::fromHtml('');
+        $ampStoryCustomElement    = $domAmpStoryCustomElement->createElement(Tag::SCRIPT);
+        $ampStoryCustomElement->setAttribute(Attribute::CUSTOM_ELEMENT, 'amp-story');
+        $domAmpStoryCustomElement->head->appendChild($ampStoryCustomElement);
+
+        $domOtherCustomElement = Document::fromHtml('');
+        $otherCustomElement    = $domOtherCustomElement->createElement(Tag::SCRIPT);
+        $otherCustomElement->setAttribute(Attribute::CUSTOM_ELEMENT, 'amp-something-else');
+        $domOtherCustomElement->head->appendChild($otherCustomElement);
+
+        $domAmpStoryCustomTemplate = Document::fromHtml('');
+        $ampStoryCustomTemplate    = $domAmpStoryCustomTemplate->createElement(Tag::SCRIPT);
+        $ampStoryCustomTemplate->setAttribute(Attribute::CUSTOM_TEMPLATE, 'amp-story');
+        $domAmpStoryCustomTemplate->head->appendChild($ampStoryCustomTemplate);
+
+        return [
+            'amp-story-custom-element' => [$domAmpStoryCustomElement, true],
+            'other-custom-element'     => [$domOtherCustomElement, false],
+            'amp-story-template'       => [$domAmpStoryCustomTemplate, false],
+        ];
+    }
+
+    /**
+     * Test the check for whether a document is an AMP Story.
+     *
+     * @dataProvider dataIsAmpStory
+     * @covers       Amp::isAmpStory()
+     *
+     * @param Document $document Document to get check for an AMP Story.
+     * @param bool     $expected Expected result.
+     */
+    public function testIsAmpStory(Document $document, $expected)
+    {
+        $this->assertEquals($expected, Amp::isAmpStory($document));
+    }
+
+    /**
+     * Provide data for the testIsTemplate() method.
+     *
+     * @return array[] Array
+     */
+    public function dataIsTemplate()
+    {
+        $dom = new Document();
+
+        $templateScript = $dom->createElement(Tag::SCRIPT);
+        $templateScript->setAttribute(Attribute::TEMPLATE, Extension::MUSTACHE);
+
+        return [
+            'non-element'         => [$dom->createTextNode('template'), false],
+            'template-element'    => [$dom->createElement(Tag::TEMPLATE), true],
+            'template-script'     => [$templateScript, true],
+            'non-template-script' => [$dom->createElement(Tag::SCRIPT), false],
+        ];
+    }
+
+    /**
+     * Test the check whether a given node is an AMP template.
+     *
+     * @dataProvider dataIsTemplate
+     * @covers       Amp::isTemplate()
+     *
+     * @param DOMNode $node     Node to check.
+     * @param bool    $expected Expected boolean result.
+     */
+    public function testIsTemplate(DOMNode $node, $expected)
+    {
+        $this->assertEquals($expected, Amp::isTemplate($node));
+    }
+
     /**
      * Create an AMP CDN script to a given URL.
      *
@@ -234,4 +311,38 @@ protected function createExtensionScript(Document $dom, $name, $type = Attribute
         $element->setAttribute($type, $name);
         return $element;
     }
+
+    /**
+     * Provide data for the testIsAmpIframe() method.
+     *
+     * @return array[] Array
+     */
+    public function dataIsAmpIframe()
+    {
+        $dom = new Document();
+
+        $templateScript = $dom->createElement(Tag::SCRIPT);
+        $templateScript->setAttribute(Attribute::TEMPLATE, Extension::MUSTACHE);
+
+        return [
+            'non-element'              => [$dom->createTextNode(Extension::IFRAME), false],
+            'amp-iframe-element'       => [$dom->createElement(Extension::IFRAME), true],
+            'amp-video-iframe-element' => [$dom->createElement(Extension::VIDEO_IFRAME), true],
+            'other-element'            => [$dom->createElement(Extension::VIDEO), false],
+        ];
+    }
+
+    /**
+     * Test the check whether a given node is an AMP iframe.
+     *
+     * @dataProvider dataIsAmpIframe
+     * @covers       Amp::isAmpIframe()
+     *
+     * @param DOMNode $node     Node to check.
+     * @param bool    $expected Expected boolean result.
+     */
+    public function testIsAmpIframe(DOMNode $node, $expected)
+    {
+        $this->assertEquals($expected, Amp::isAmpIframe($node));
+    }
 }