hugo/tpl/tplimpl/embedded/templates/opengraph.html

<meta property="og:title" content="{{ .Title }}" />
<meta property="og:description" content="{{ with .Description }}{{ . }}{{ else }}{{if .IsPage}}{{ .Summary }}{{ else }}{{ with .Site.Params.description }}{{ . }}{{ end }}{{ end }}{{ end }}" />
<meta property="og:type" content="{{ if .IsPage }}article{{ else }}website{{ end }}" />
<meta property="og:url" content="{{ .Permalink }}" />
{{ with $.Param "images" }}{{ range first 6 . }}
<meta property="og:image" content="{{ . | absURL }}" />
{{ end }}{{ 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" {{ .Date.Format $iso8601 | printf "content=%q" | safeHTMLAttr }} />
{{- end }}
{{- end }}{{/* .IsPage */}}

{{- with .Params.audio }}<meta property="og:audio" content="{{ . }}" />{{ end }}
{{- with .Params.locale }}<meta property="og:locale" content="{{ . }}" />{{ end }}
{{- with .Site.Params.title }}<meta property="og:site_name" content="{{ . }}" />{{ end }}
{{- with .Params.videos }}
{{- range . }}
<meta property="og:video" content="{{ . | absURL }}" />
{{ end }}{{ end }}

{{- /* If it is part of a series, link to related articles */}}
{{- $permalink := .Permalink }}
{{- $siteSeries := .Site.Taxonomies.series }}{{ with .Params.series }}
{{- range $name := . }}
  {{- $series := index $siteSeries $name }}
  {{- range $page := first 6 $series.Pages }}
    {{- if ne $page.Permalink $permalink }}<meta property="og:see_also" content="{{ $page.Permalink }}" />{{ end }}
  {{- end }}
{{ end }}{{ end }}

{{- if .IsPage }}
{{- range .Site.Authors }}{{ with .Social.facebook }}
<meta property="article:author" content="https://www.facebook.com/{{ . }}" />{{ end }}{{ with .Site.Social.facebook }}
<meta property="article:publisher" content="https://www.facebook.com/{{ . }}" />{{ end }}
<meta property="article:section" content="{{ .Section }}" />
{{- with .Params.tags }}{{ range first 6 . }}
<meta property="article:tag" content="{{ . }}" />{{ end }}{{ end }}
{{- end }}{{ end }}

{{- /* Facebook Page Admin ID for Domain Insights */}}
{{- with .Site.Social.facebook_admin }}<meta property="fb:admins" content="{{ . }}" />{{ end }}