Meta Tagger Snippet for Expo Theme

Fixed up and modernized Expo gist

<link rel="canonical" href="{{ canonical_url }}" />
{% assign maxmeta = 155 %}
{% if template contains 'product' %}
  {% assign mf = product.metafields.meta_data %}
  {% unless mf == empty %}
    {% for mf in product.metafields.meta_data' %}
      {% capture key %}{{ mf | first }}{% endcapture %}
      {% if key == 'title' %}
        <title>{{mf | last}}</title>
        <meta name="title" content="{{mf | last}}" />
      {% endif %}
      {% if key == 'meta_description' %}
        <meta name="description" content="{{mf | last}}" />
      {% endif %}
      {% if key == 'keywords' %}
        <meta name="keywords" content="{{mf | last}}" />
      {% endif %}
    {% endfor %}
  {% else %}
     <title>{{ page_title | escape }}</title>
     <meta name="description" content="{{product.description | strip_html | strip_newlines | truncate: maxmeta | escape}}" />
  {% endunless %}
{% elsif template contains 'page' %}
  {% assign mf = page.metafields.meta_data %}
  {% unless mf == empty %}
    {% for mf in page.metafields.meta_data' %}
      {% capture key%}{{ mf | first }}{%endcapture%}
      {% if key == 'title' %}
        <title>{{mf | last}}</title>
        <meta name="title" content="{{mf | last}}" />
      {% endif %}
      {% if key == 'meta_description' %}
        <meta name="description" content="{{mf | last}}" />
      {% endif %}
      {% if key == 'keywords' %}
        <meta name="keywords" content="{{mf | last}}" />
      {% endif %}
    {% endfor %}
  {% else %}
      <title>{{ page_title | escape }}</title>
     <meta name="description" content="{{page.content | strip_html | strip_newlines | truncate: maxmeta | escape}}" />
  {% endunless %}
{% elsif template contains 'collection' %}
  {% assign mf = collection.metafields.meta_data %}
  {% unless mf == empty or mf == nil %}
    {% for mf in collection.metafields.meta_data' %}
      {% capture key%}{{ mf | first }}{%endcapture%}
      {% if key == 'title' %}
        <title>{{mf | last}}</title>
        <meta name="title" content="{{mf | last}}" />
      {% endif %}
      {% if key == 'meta_description' %}
        <meta name="description" content="{{mf | last}}" />
      {% endif %}
      {% if key == 'keywords' %}
        <meta name="keywords" content="{{mf | last}}" />
      {% endif %}
    {% endfor %}
  {% else %}
    <title>{{ shop.name }} - {{ page_title | escape }}</title>
    <meta name="description" content="{{collection.description | strip_html | strip_newlines | truncate: maxmeta | escape}}" />
  {% endunless %}
  
{% elsif template contains 'index' %}
  <title>{% if settings.title_tags != "" %}{{ settings.title_tags }}{% endif %} - {{ page_title | escape }}</title>
  {% if settings.meta_description != '' %}
    <meta name="description" content="{{settings.meta_description | escape }}" />
  {% elsif shop.description != '' %}
     <meta name="description" content="{{shop.description | escape }}" />
  {% endif %}
  {% if settings.meta_keywords != '' %}
     <meta name="keywords" content="{{settings.meta_keywords | escape }}" />
  {% endif %}

{% elsif template contains 'blog' %}
    {% assign mf = blog.metafields.meta_data %}
    {% unless mf == empty %}
        {% for mf in blog.metafields.meta_data %}
            {% capture key %}{{ mf | first }}{% endcapture %}
            {% if key == 'title' %}
                <title>{{mf | last}}</title>
                <meta name="title" content="{{mf | last}}" />
            {% endif %}
            {% if key == 'meta_description' %}
                <meta name="description" content="{{mf | last}}" />
            {% endif %}
            {% if key == 'keywords' %}
                <meta name="keywords" content="{{mf | last}}" />
            {% endif %}
        {% endfor %}
  {% else %}
    <title>{{ page_title | escape }}</title>
    <meta name="description" content="{{ shop.name }} {{ blog.title | escape }} blog" /> 
  {%endunless %}
{% elsif template contains 'article' %}
  <title>{{ page_title | escape }}</title>
  <meta name="description" content=" {{ article.excerpt_or_content | strip_html | strip_newlines | escape | truncate: maxmeta  }}" />
{% else %}  
  <title>{{ shop.name }} - {{ page_title | escape }}{% if settings.title_tags != "" %} - {{ settings.title_tags }}{% endif %}{% if template == "404" %} ==> Page Not Found <== {% endif %}</title>
  {% if settings.meta_description != '' %}
    <meta name="description" content="{{settings.meta_description | escape }}" />
  {% elsif shop.description != '' %}
     <meta name="description" content="{{shop.description | escape }}" />
  {% endif %}
  {% if settings.meta_keywords != '' %}
     <meta name="keywords" content="{{settings.meta_keywords | escape }}" />
  {% endif %}
{% endif %}

gistfile1.html

{% assign maxmeta = 155 %}
{% if template contains 'product' %}
  {% if collection %}
    <link rel="canonical" href="{{ shop.url }}{{ product.url }}" />
  {% endif %}
  {% assign mf = product.metafields.meta_data %}
  {% unless mf == empty %}
    {% for mf in product.metafields.meta_data' %}
      {% capture key %}{{ mf | first }}{% endcapture %}
      {% if key == 'title' %}
        <title>{{mf | last}}</title>
        <meta name="title" content="{{mf | last}}" />
      {% endif %}
      {% if key == 'meta_description' %}
        <meta name="description" content="{{mf | last}}" />
      {% endif %}
      {% if key == 'keywords' %}
        <meta name="keywords" content="{{mf | last}}" />
      {% endif %}
    {% endfor %}
  {% else %}
     <title>{% if page_title != '' %}{{ page_title | escape }}{% else %}{{product.title}}{% endif %}</title>
     <meta name="description" content="{{product.description | strip_html | strip_newlines | truncate: maxmeta | escape}}" />
  {% endunless %}
{% elsif template contains 'page' %}
  {% assign mf = page.metafields.meta_data %}
  {% unless mf == empty %}
    {% for mf in page.metafields.meta_data' %}
      {% capture key%}{{ mf | first }}{%endcapture%}
      {% if key == 'title' %}
        <title>{{mf | last}}</title>
        <meta name="title" content="{{mf | last}}" />
      {% endif %}
      {% if key == 'meta_description' %}
        <meta name="description" content="{{mf | last}}" />
      {% endif %}
      {% if key == 'keywords' %}
        <meta name="keywords" content="{{mf | last}}" />
      {% endif %}
    {% endfor %}
  {% else %}
      <title>{% if page_title != '' %}{{ page_title | escape }}{% else %}{{page.title}}{% endif %}</title>
     <meta name="description" content="{{page.content | strip_html | strip_newlines | truncate: maxmeta | escape}}" />
  {% endunless %}
{% elsif template contains 'collection' %}
  {% assign mf = collection.metafields.meta_data %}
  {% unless mf == empty or mf == nil %}
    {% for mf in collection.metafields.meta_data' %}
      {% capture key%}{{ mf | first }}{%endcapture%}
      {% if key == 'title' %}
        <title>{{mf | last}}</title>
        <meta name="title" content="{{mf | last}}" />
      {% endif %}
      {% if key == 'meta_description' %}
        <meta name="description" content="{{mf | last}}" />
      {% endif %}
      {% if key == 'keywords' %}
        <meta name="keywords" content="{{mf | last}}" />
      {% endif %}
    {% endfor %}
  {% else %}
    <title>{{ shop.name }} - {% if page_title != '' %}{{ page_title | escape }}{% else %}{{collection.title}}{% endif %}</title>
    <meta name="description" content="{{collection.description | strip_html | strip_newlines | truncate: maxmeta | escape}}" />
  {% endunless %}
  
{% elsif template contains 'index' %}
  <title>{{ shop.name }} - {{ page_title | escape }}{% if settings.title_tags != "" %} - {{ settings.title_tags }}{% endif %}</title>
  {% if settings.meta_description != '' %}
    <meta name="description" content="{{settings.meta_description | escape }}" />
  {% elsif shop.description != '' %}
     <meta name="description" content="{{shop.description | escape }}" />
  {% endif %}
  {% if settings.meta_keywords != '' %}
     <meta name="keywords" content="{{settings.meta_keywords | escape }}" />
  {% endif %}

{% elsif template contains 'blog' %}
  <title>{% if page_title != '' %}{{ page_title | escape }}{% else %}{{ blog.title }} {{ shop.name }}{% endif %}</title>
  <meta name="description" content="{{ shop.name }} {{ blog.title | escape }} blog" /> 
{% elsif template contains 'article' %}
  <title>{% if page_title != '' %}{{ page_title | escape }}{% else %}{{ shop.name }} - {{ article.title }}{% endif %}</title>
  <meta name="description" content=" {{ article.excerpt_or_content | strip_html | strip_newlines | escape | truncate: maxmeta  }}" />
{% else %}  
  <title>{{ shop.name }} - {{ page_title | escape }}{% if settings.title_tags != "" %} - {{ settings.title_tags }}{% endif %}{% if template == "404" %} ==> Page Not Found <== {% endif %}</title>
  {% if settings.meta_description != '' %}
    <meta name="description" content="{{settings.meta_description | escape }}" />
  {% elsif shop.description != '' %}
     <meta name="description" content="{{shop.description | escape }}" />
  {% endif %}
  {% if settings.meta_keywords != '' %}
     <meta name="keywords" content="{{settings.meta_keywords | escape }}" />
  {% endif %}
{% endif %}