authelia/docs/layouts/partials/head/opengraph.html

<meta property="og:locale" content="{{ .Site.Params.ogLocale }}">
<meta property="og:type" content="{{ if .IsPage }}article{{ else }}website{{ end }}">
{{ if .IsHome -}}
<meta property="og:title" content="{{ .Site.Params.title }} {{ .Site.Params.titleSeparator }} {{ .Site.Params.titleAddition }}">
{{ else -}}
<meta property="og:title" content="{{ .Title }} {{ .Site.Params.titleSeparator }} {{ humanize .Section }}">
{{ end -}}
<meta property="og:description" content="{{ with .Description }}{{ . }}{{ else }}{{if .IsPage}}{{ .Summary }}{{ else }}{{ with .Site.Params.description }}{{ . }}{{ end }}{{ end }}{{ end }}">
{{ if $.Scratch.Get "paginator" -}}
  {{ $paginator := .Paginate (where .Site.RegularPages.ByDate.Reverse "Section" "blog" ) -}}
  <meta property="og:url" content="{{ .Paginator.URL | absURL }}">
{{ else -}}
  <meta property="og:url" content="{{ .Permalink }}">
{{ end -}}
{{ with .Site.Params.title -}}
  <meta property="og:site_name" content="{{ . }}">
{{ end -}}

{{ $iso8601 := "2006-01-02T15:04:05-07:00" -}}
{{ if .IsPage -}}
  {{ if not .PublishDate.IsZero -}}
    <meta property="article:published_time" {{ .PublishDate.Format $iso8601 | printf "content=%q" | safeHTMLAttr }}>
  {{ else if not .Date.IsZero -}}
    <meta property="article:published_time" {{ .Date.Format $iso8601 | printf "content=%q" | safeHTMLAttr }}>
  {{ end -}}
  {{ if not .Lastmod.IsZero -}}
    <meta property="article:modified_time" {{ .Lastmod.Format $iso8601 | printf "content=%q" | safeHTMLAttr }}>
  {{ end -}}
{{ else -}}
  {{ if not .Date.IsZero -}}
    <meta property="og:updated_time" {{ .Lastmod.Format $iso8601 | printf "content=%q" | safeHTMLAttr }}>
  {{ end -}}
{{ end -}}

{{ if eq .Kind "home" -}}
  {{ .Scratch.Set "title" .Site.Params.titleHome -}}
{{ else -}}
  {{ .Scratch.Set "title" .Title -}}
{{ end -}}

{{ with $.Params.images -}}
  {{ range first 6 . -}}
  <meta property="og:image" content="{{ $.Permalink }}{{ . }}">
  {{ end -}}
{{ else -}}
  {{ $images := $.Resources.ByType "image" -}}
  {{ $featured := $images.GetMatch "*feature*" -}}
  {{ if not $featured -}}
    {{ $featured = $images.GetMatch "{*cover*,*thumbnail*}" }}
  {{ end -}}
  {{ with $featured -}}
    <meta property="og:image" content="{{ $featured.Permalink }}"/>
  {{ else -}}
    {{ with $.Site.Params.images -}}
      <meta property="og:image" content="{{ index . 0 | absURL }}"/>
      <meta property="og:image:alt" content="{{ $.Site.Params.title }}">
    {{ end -}}
  {{ end -}}
{{ end -}}

{{ with $.Site.Params.images -}}
  {{ $.Scratch.Set "primaryImage" (index . 0 | absURL) -}}
{{ end -}}

{{ with .Params.audio -}}
  <meta property="og:audio" content="{{ . | absURL }}">
{{ end -}}

{{ with .Params.videos -}}
  {{ range . -}}
    <meta property="og:video" content="{{ . | absURL }}">
  {{ end -}}
{{ end -}}