{"id":762,"date":"2008-03-02T14:58:54","date_gmt":"2008-03-02T13:58:54","guid":{"rendered":"http:\/\/notizblog.org\/2008\/03\/02\/rdfa-basics\/"},"modified":"2020-05-05T16:18:14","modified_gmt":"2020-05-05T14:18:14","slug":"rdfa-basics","status":"publish","type":"post","link":"https:\/\/notiz.blog\/2008\/03\/02\/rdfa-basics\/","title":{"rendered":"RDFa Basics"},"content":{"rendered":"\n<p>Wer sich viel mit <a href=\"http:\/\/microformats.org\">Microformats<\/a> besch\u00e4ftigt, ist sicher schon \u00f6fters \u00fcber den Begriff RDFa gestolpert. Die Idee, (X)HTML semantischer zu machen, ist bei beiden Formaten gleich, der Unterschied liegt haupts\u00e4chlich in der Syntax.<br> W\u00e4hrend Microformats ausschlie\u00dflich auf HTML 4.01 bzw. XHTML 1.0 validen Tags und Attributen basiert:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-1\" data-shcb-language-name=\"HTML, XML\" data-shcb-language-slug=\"xml\"><span><code class=\"hljs language-xml\"><span class=\"hljs-tag\">&lt;<span class=\"hljs-name\">div<\/span> <span class=\"hljs-attr\">class<\/span>=<span class=\"hljs-string\">\"vcard\"<\/span>&gt;<\/span>\n  <span class=\"hljs-tag\">&lt;<span class=\"hljs-name\">span<\/span> <span class=\"hljs-attr\">class<\/span>=<span class=\"hljs-string\">\"fn\"<\/span>&gt;<\/span>Max Mustermann<span class=\"hljs-tag\">&lt;\/<span class=\"hljs-name\">span<\/span>&gt;<\/span>\n  <span class=\"hljs-tag\">&lt;<span class=\"hljs-name\">a<\/span> <span class=\"hljs-attr\">class<\/span>=<span class=\"hljs-string\">\"email\"<\/span> <span class=\"hljs-attr\">href<\/span>=<span class=\"hljs-string\">\"mailto:max.mustermann@example.org\"<\/span>&gt;<\/span>\n    max.mustermann@example.org\n  <span class=\"hljs-tag\">&lt;\/<span class=\"hljs-name\">a<\/span>&gt;<\/span>\n<span class=\"hljs-tag\">&lt;\/<span class=\"hljs-name\">div<\/span>&gt;<\/span><\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-1\"><span class=\"shcb-language__label\">Code-Sprache:<\/span> <span class=\"shcb-language__name\">HTML, XML<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">xml<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>Beispiel <a href=\"http:\/\/microformats.org\/wiki\/hCard\">hCard<\/a><\/p>\n\n\n\n<p>&#8230;basiert RDFa auf dem klassischen <a href=\"http:\/\/www.w3.org\/TR\/rdf-primer\/\"><abbr title=\"Resource Description Framework\">RDF<\/abbr><\/a> und mit XHTML 2.0 neu eingef\u00fchrten Attributen wie z.B. <code>property<\/code> und <code>about<\/code>:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-2\" data-shcb-language-name=\"HTML, XML\" data-shcb-language-slug=\"xml\"><span><code class=\"hljs language-xml\"><span class=\"hljs-tag\">&lt;<span class=\"hljs-name\">body<\/span> <span class=\"hljs-attr\">xmlns:contact<\/span>=<span class=\"hljs-string\">\"http:\/\/www.w3.org\/2001\/vcard-rdf\/3.0#\"<\/span>&gt;<\/span>\n  <span class=\"hljs-tag\">&lt;<span class=\"hljs-name\">span<\/span> <span class=\"hljs-attr\">property<\/span>=<span class=\"hljs-string\">\"contact:fn\"<\/span>&gt;<\/span>Max Mustermann<span class=\"hljs-tag\">&lt;\/<span class=\"hljs-name\">span<\/span>&gt;<\/span>\n  <span class=\"hljs-tag\">&lt;<span class=\"hljs-name\">a<\/span> <span class=\"hljs-attr\">rel<\/span>=<span class=\"hljs-string\">\"contact:email\"<\/span> <span class=\"hljs-attr\">href<\/span>=<span class=\"hljs-string\">\"mailto:max.mustermann@example.org\"<\/span>&gt;<\/span>\n    max.mustermann@example.org\n  <span class=\"hljs-tag\">&lt;\/<span class=\"hljs-name\">a<\/span>&gt;<\/span>\n<span class=\"hljs-tag\">&lt;\/<span class=\"hljs-name\">body<\/span>&gt;<\/span><\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-2\"><span class=\"shcb-language__label\">Code-Sprache:<\/span> <span class=\"shcb-language__name\">HTML, XML<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">xml<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>Beispiel <a href=\"http:\/\/www.w3.org\/TR\/vcard-rdf\">vCard RDF<\/a> in <a href=\"http:\/\/www.w3.org\/TR\/xhtml-rdfa-primer\/#publishing-contact-info\">RDFa<\/a><\/p>\n\n\n\n<p>Eine gute Einf\u00fchrung in das Thema RDFa bietet das Video von Manu Sporny:<\/p>\n\n\n\n<figure class=\"wp-block-embed-youtube alignwide wp-block-embed is-type-video is-provider-youtube wp-embed-aspect-4-3 wp-has-aspect-ratio\"><div class=\"wp-block-embed__wrapper\">\n\t\t<div class=\"embed-privacy-container is-disabled embed-youtube\" data-embed-id=\"oembed_0e14e3474bae0439a79d75906b90853d\" data-embed-provider=\"youtube\" style=\"background-image: url(https:\/\/notiz.blog\/wp-content\/uploads\/embed-privacy\/thumbnails\/youtube-ldl0m-5zLz4-hqdefault.jpg?ver=1.12.4); aspect-ratio: 700\/525;\">\t\t\t\t\t\t<button type=\"button\" class=\"embed-privacy-enable screen-reader-text\">\u201eRDFa Basics\u201c von YouTube anzeigen<\/button>\t\t\t\t\t\t<div class=\"embed-privacy-overlay\">\t\t\t\t<div class=\"embed-privacy-inner\">\t\t\t\t\t<div class=\"embed-privacy-logo\" style=\"background-image: url(https:\/\/notiz.blog\/wp-content\/plugins\/embed-privacy\/assets\/images\/embed-youtube.png?ver=1.12.4);\"><\/div>\t\t<p>\t\tHier klicken, um den Inhalt von YouTube anzuzeigen.\t\t\t\t\t<br>\t\t\t\t\tErfahre mehr in der <a href=\"https:\/\/policies.google.com\/privacy?hl=de\" target=\"_blank\">Datenschutzerkl\u00e4rung von YouTube<\/a>.\t\t<\/p>\t\t<p class=\"embed-privacy-input-wrapper\">\t\t\t<input id=\"embed-privacy-store-youtube-0e14e3474bae0439a79d75906b90853d\" type=\"checkbox\" value=\"1\" class=\"embed-privacy-input\" data-embed-provider=\"youtube\">\t\t\t<label for=\"embed-privacy-store-youtube-0e14e3474bae0439a79d75906b90853d\" class=\"embed-privacy-label\" data-embed-provider=\"youtube\">\t\t\t\tInhalt von YouTube immer anzeigen\t\t\t<\/label>\t\t<\/p>\t\t\t\t\t\t<\/div>\t\t\t\t\t\t\t\t<div class=\"embed-privacy-footer\"><span class=\"embed-privacy-url\"><a href=\"https:\/\/www.youtube.com\/watch?v=ldl0m-5zLz4\">\u201eRDFa Basics\u201c direkt \u00f6ffnen<\/a><\/span><\/div>\t\t\t<\/div>\t\t\t\t\t\t<div class=\"embed-privacy-content\">\t\t\t\t<script>var _oembed_0e14e3474bae0439a79d75906b90853d = '{\\\"embed\\\":\\\"&lt;iframe title=&quot;RDFa Basics&quot; width=&quot;700&quot; height=&quot;525&quot; src=&quot;https:\\\\\/\\\\\/www.youtube-nocookie.com\\\\\/embed\\\\\/ldl0m-5zLz4?feature=oembed&quot; frameborder=&quot;0&quot; allow=&quot;accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share&quot; referrerpolicy=&quot;strict-origin-when-cross-origin&quot; allowfullscreen&gt;&lt;\\\\\/iframe&gt;\\\"}';<\/script>\t\t\t<\/div>\t\t<\/div>\t\t\n<\/div><\/figure>\n\n\n\n<p>Rein Technisch gesehen ist RDFa, durch die Nutzung von Namespaces und die bessere Skalierbarkeit durch URIs, definitiv der bessere Standard. Ich denke trotzdem nicht dass RDFa die Microformats in n\u00e4herer Zukunft abl\u00f6sen wird, da RDFa nur unter XHTML 2.0 m\u00f6glich ist und (meines Wissens) im Konkurrenz-Format (X)HTML 5.0 nicht angedacht wird. Es ist deshalb notwendig beide Formate weiter voranzutreiben und so weit wie m\u00f6glich auf einem einheitlichen Standard, wie z.B. der vCard im oben beschriebenen Beispiel, aufzubauen. W\u00e4hrend der \u00dcbergangsphase ist es so relativ einfach mit <a href=\"http:\/\/www.w3.org\/TR\/grddl\/\"><abbr title=\"Gleaning Resource Descriptions from Dialects of Languages\">GRDDL<\/abbr><\/a> zwischen den beiden Formaten zu transformieren.<\/p>\n\n\n\n<p>In seinem Artikel &#8222;<a href=\"https:\/\/web.archive.org\/web\/20130531033506\/http:\/\/evan.prodromou.name:80\/RDFa_vs_microformats\">RDFa vs microformats<\/a>&#8220; beschreibt Evan Prodromou die f\u00fcr ihn notwendigen Schritte f\u00fcr die Zukunft von RDFa:<\/p>\n\n\n\n<ol class=\"wp-block-list\"><li>RDFa gets acknowledged and embraced by microformats.org as the future of semantic-data-in-XHTML<\/li><li>The RDFa group makes an effort to encompass existing microformats with a minimum of changes<\/li><li>microformats.org leaders join in on the RDFa authorship process<\/li><li>microformats.org becomes a focus for developing real-world RDFa vocabularies<\/li><\/ol>\n\n\n\n<p>Mal schauen wie es wirklich kommt und was sich in Zukunft durchsetzen wird&#8230;<\/p>\n\n\n\n<p>Wer sich f\u00fcr das Thema interessiert, kann ja mal <a href=\"https:\/\/web.archive.org\/web\/20160502022446\/http:\/\/sioc-project.org:80\/firefox\">Semantic Radar f\u00fcr Firefox<\/a> ausprobieren. Semantic Radar macht (\u00e4hnlich wie Operator f\u00fcr Microformats) RDF und RDFa Inhalte in Webseiten sichtbar.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Wer sich viel mit Microformats besch\u00e4ftigt, ist sicher schon \u00f6fters \u00fcber den Begriff RDFa gestolpert. Die Idee, (X)HTML semantischer zu machen, ist bei beiden Formaten gleich, der Unterschied liegt haupts\u00e4chlich in der Syntax. W\u00e4hrend Microformats ausschlie\u00dflich auf HTML 4.01 bzw. XHTML 1.0 validen Tags und Attributen basiert: Beispiel hCard &#8230;basiert RDFa auf dem klassischen RDF [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"webmentions_disabled_pings":false,"webmentions_disabled":false,"activitypub_content_warning":"","activitypub_content_visibility":"","activitypub_max_image_attachments":4,"activitypub_interaction_policy_quote":"anyone","activitypub_status":"","footnotes":""},"categories":[2],"tags":[166,164,104,527,532,381],"class_list":{"0":"post-762","1":"post","2":"type-post","3":"status-publish","4":"format-standard","6":"category-web","7":"tag-hcard","8":"tag-microformats","9":"tag-rdf","10":"tag-rdfa","11":"tag-triples","12":"tag-vcard","13":"h-entry","14":"hentry"},"_links":{"self":[{"href":"https:\/\/notiz.blog\/wp-api\/wp\/v2\/posts\/762","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/notiz.blog\/wp-api\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/notiz.blog\/wp-api\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/notiz.blog\/wp-api\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/notiz.blog\/wp-api\/wp\/v2\/comments?post=762"}],"version-history":[{"count":0,"href":"https:\/\/notiz.blog\/wp-api\/wp\/v2\/posts\/762\/revisions"}],"wp:attachment":[{"href":"https:\/\/notiz.blog\/wp-api\/wp\/v2\/media?parent=762"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/notiz.blog\/wp-api\/wp\/v2\/categories?post=762"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/notiz.blog\/wp-api\/wp\/v2\/tags?post=762"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}