{%- if seo_title -%}
{%- assign seo_title = seo_title | markdownify | strip_html | strip_newlines | escape_once -%}
{%- endif -%}
{% if page.canonical_url %}
{%- assign canonical_url = page.canonical_url %}
{% else %}
{%- assign canonical_url = page.url | replace: "index.html", "" | absolute_url %}
{% endif %}
{%- assign seo_description = page.description | default: page.excerpt | default: site.description -%}
{%- if seo_description -%}
{%- assign seo_description = seo_description | markdownify | strip_html | strip_newlines | escape_once -%}
{%- endif -%}
{%- assign author = page.author | default: page.authors[0] | default: site.author -%}
{%- assign author = site.data.authors[author] | default: author -%}
{%- if author.twitter -%}
{%- assign author_twitter = author.twitter | replace: "@", "" -%}
{%- endif -%}
{%- if page.date -%}
{%- assign og_type = "article" -%}
{%- else -%}
{%- assign og_type = "website" -%}
{%- endif -%}
{% if author.name %}
{% endif %}
{% unless page.layout == 'post' %}
{% endunless%}
{% if page.layout == 'post'%}
{% endif %}