Meta Tags, with Open Graph and Facebook, Umbraco, XSLT

meta.xsl

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet
  version="1.0"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  xmlns:umb="urn:umbraco.library"

  exclude-result-prefixes="umb"
>

  <xsl:output method="xml" omit-xml-declaration="yes"/>
  <xsl:param name="currentPage"/>

  <!-- Meta, Laurie 5th September 2011 -->

  <xsl:template match="/">
    <!-- Title -->
    <!-- <xsl:value-of select="($currentPage/metaTitle | $currentPage/@nodeName[not(normalize-space($currentPage/metaTitle))])[1]" /> -->
    <xsl:if test="($currentPage/metaKeywords | $currentPage/ancestor-or-self::publicHome/metaKeywords[not(normalize-space($currentPage/metaKeywords))])[1] !=''">
      <meta name="keywords" content="{($currentPage/metaKeywords | $currentPage/ancestor-or-self::publicHome/metaKeywords[not(normalize-space($currentPage/metaKeywords))])[1]}" />
    </xsl:if>
    <xsl:if test="$currentPage/metaDescription !=''">
      <meta name="description" content="{$currentPage/metaDescription}" />
    </xsl:if>
	<!-- If Russian, include Russian fonts -->
	<xsl:if test="$currentPage/ancestor-or-self::Home/@id = '1425'">
		<link href="http://fonts.googleapis.com/css?family=PT+Sans:700&amp;subset=cyrillic" rel="stylesheet" type="text/css" />
	</xsl:if>
	<xsl:if test="$currentPage/contentPublicationURL != ''">
		<link rel="canonical" href="{$currentPage/contentPublicationURL}"/>
	</xsl:if>
  </xsl:template>
	
  <!-- OpenGraph Social -->
  	
	
	<meta property="og:title" content="{($currentPage/contentHeader | $currentPage/@nodeName[not(normalize-space($currentPage/contentHeader))])[1]}"/>
	<meta property="og:type" content="article"/>
	<meta property="og:url" content="{umb:NiceUrl($currentPage/@id)}"/>
	
	<meta property="og:description" content="{$currentpage/metaDescription}"/>
	<meta property="article:author" content=""/>

	<meta name="twitter:site" content=""/>
	<meta name="twitter:title" content="{($currentPage/contentHeader | $currentPage/@nodeName[not(normalize-space($currentPage/contentHeader))])[1]}"/>	
	
	<xsl:choose>
		<xsl:when test="$currentPage/contentImage != ''">
			<meta name="twitter:card" content="photo" />
			<meta name="twitter:image:src" content="{umb:GetMedia($currentPage/propertyAlias, 0)/umbracoFile}" />
			<meta property="og:image" content="{umb:GetMedia($currentPage/propertyAlias, 0)/umbracoFile}" />
		</xsl:when>
		<xsl:otherwise>
			<meta name="twitter:card" value="summary" />
		</xsl:otherwise>
	</xsl:choose>


</xsl:stylesheet>