website/_src/_includes/sharing.html

<!-- Twitter Cards -->
<meta name="twitter:card" content="summary_large_image">
<meta name="twitter:site" content="@ipdbfoundation">

{% if page.front_page %}
    <meta name="twitter:title" content="{{ site.title }}">
{% else %}
    <meta name="twitter:title" content="{{ page.title }} · {{ site.title }}">
{% endif %}

{% if page.url %}
    <meta name="twitter:url" content="{{ site.url}}{{ page.url | replace:'index.html','' }}">
{% endif %}

{% if page.description %}
    <meta name="twitter:description" content="{{ page.description }}">
{% elsif page.front_page %}
    <meta name="twitter:description" content="{{ site.data.content-front.hero.description | strip_html | strip_newlines }}">
{% else %}
    <meta name="twitter:description" content="{{ page.excerpt | strip_html }}">
{% endif %}

{% if page.image %}
    <meta name="twitter:image:src" content="{{ site.url }}/assets/img/{{ page.image }}">
{% else %}
    <meta name="twitter:image:src" content="{{ site.url }}/assets/img/share-image.jpg">
{% endif %}


<!-- Open Graph -->
<meta property="og:type" content="website">
<meta property="og:site_name" content="{{ site.title }}">

{% if page.front_page %}
    <meta property="og:title" content="{{ site.title }}">
{% else %}
    <meta property="og:title" content="{{ page.title }} · {{ site.title }}">
{% endif %}

{% if page.description %}
    <meta property="og:description" content="{{ page.description }}">
{% elsif page.front_page %}
    <meta property="og:description" content="{{ site.data.content-front.hero.description | strip_html | strip_newlines }}">
{% else %}
    <meta property="og:description" content="{{ page.excerpt | strip_html | strip_newlines }}">
{% endif %}

{% if page.url %}
    <meta property="og:url" content="{{ site.url}}{{ page.url | replace:'index.html','' }}">
{% endif %}

{% if page.date %}
    <meta property="article:published_time" content="{{ page.date | date_to_xmlschema }}">
{% endif %}

{% if page.image %}
    <meta content="{{ site.url }}/assets/img/{{ page.image }}" property="og:image">
{% else %}
    <meta content="{{ site.url }}/assets/img/share-image.png" property="og:image">
{% endif %}