This code is for a Stack Overflow question about displaying related products in a Shopify theme using product tags.

README.md

This code is for a Stack Overflow question about displaying related products in a Shopify theme using product tags.

Relevant Links:

• Question on Stack Overflow
• Article on Shopify wiki about how to implement related products (esp. section 3. Finding a relevant collection)
• Related products gist from section 3 of the above article

related-products-by-tag-1.html

{% if settings.products_per_row == "3" or settings.products_per_row == "4" %}
  {% assign number_of_related_products_to_show = settings.products_per_row | times: 1 %}
{% else %}
  {% assign number_of_related_products_to_show = 2 %}
{% endif %}

{% assign current_product = product %}
{% assign current_product_tags = product.tags %}
{% assign found_first_match = false %}
{% assign found_second_match = false %}
{% assign first_related_product = true %}

{% paginate collections.all.products by 1000 %}
{% for product in collections.all.products %}
  {% unless product.handle == current_product.handle %}
    {% for tag in product.tags %}
      {% if current_product_tags contains tag and tag != 'Made in USA' %}
        {% if found_first_match == false %}
          {% assign found_first_match = true %}
          {% assign first_match = tag %}
        {% elsif found_second_match == false %}
          {% assign found_second_match = true %}
          {% assign second_match = tag %}
        {% endif %}
      {% endif %}
    {% endfor %}

    {% if found_first_match == true %}
      {% if first_related_product == true %}
        {% assign first_related_product == false %}

        <div class="row">
          <div class="span12">
            <h3 class="collection-title">Related products</h3>
          </div>
        </div>
        <div class="row products">

      {% endif %}
      {% if product.tags contains first_match or product.tags contains second_match %}
        {% include 'related-product-loop' with collection.handle %}
      {% endif %}
    {% endif %}
  {% endunless %}
{% endfor %}
{% if first_related_product == false %} </div> {% endif %}
{% endpaginate %}

{{ 'jquery.pick.js' | asset_url | script_tag }}
<script type="text/javascript" charset="utf-8">
//<![CDATA[
  var howMany = {{ number_of_related_products_to_show }};
  jQuery(function() {
    jQuery('.products .product').pick(howMany);
  });
//]]>
</script>

related-products-by-tag-2.html

{% if settings.products_per_row == "3" or settings.products_per_row == "4" %}
  {% assign number_of_related_products_to_show = settings.products_per_row | times: 1 %}
{% else %}
  {% assign number_of_related_products_to_show = 2 %}
{% endif %}

{% assign current_product = product %}
{% assign current_product_tags = product.tags %}
{% assign found_first_match = false %}

{% paginate collections.all.products by 1000 %}
{% for product in collections.all.products %}
  {% unless product.handle == current_product.handle %}
    {% for tag in product.tags %}
      {% if current_product_tags contains tag and tag != 'Made in USA' %}
        {% if found_first_match == false %}
          {% assign found_first_match = true %}
          {% assign first_match = tag %}
        {% else %}
          {% assign second_match = tag %}
        {% endif %}
      {% endif %}
    {% endfor %}
  {% endunless %}
{% endfor %}
{% endpaginate %}

{% if found_first_match == true %}

  <div class="row">
    <div class="span12">
      <h3 class="collection-title">Related products</h3>
    </div>
  </div>
  <div class="row products">

  {% paginate collections.all.products by 1000 %}
  {% for product in collections.all.products %}
    {% unless product.handle == current_product.handle %}
      {% if product.tags contains first_match or product.tags contains second_match %}
        {% include 'related-product-loop' with collection.handle %}
      {% endif %}
    {% endunless %}
  {% endfor %}
  {% endpaginate %}

  </div>

{% endif %}

{{ 'jquery.pick.js' | asset_url | script_tag }}
<script type="text/javascript" charset="utf-8">
//<![CDATA[
  var howMany = {{ number_of_related_products_to_show }};
  jQuery(function() {
    jQuery('.products .product').pick(howMany);
  });
//]]>
</script>

In the first snippet, there is a syntax error on line 30
{% assign first_related_product == false %}
Should be
{% assign first_related_product = false %}