How can I filter collections by metafields in liquid?

[maxwkf]

Hi there,

I would like to do filtering of my collections by metafields in liquid. How should I do it?

If I use the where in collection predefined fields, I can do it like this. {% assign collections = collections | where: 'description', 'promotion' %}

But while I am trying to do query on the 'group' metafield I have created, it simply not working.

{% assign collections = collections | where: 'metafields.custom.group', 'promotion' %}

I tried to use this solution (https://community.shopify.com/c/technical-q-a/filtering-collections-by-metafields-using-where/m-p/18...) and surf on the Internet and can get no useful information.

Please help Thanks

[maxwkf · Accepted solution]

I think the where in liquid won't be able to support a dot operator to retrieve nested array value.

The following is the definition of where in ruby.  Unless array in Ruby support dot operator property value like 'metafields.custom.group', it cannot support for what I mentioned.

# @liquid_public_docs
    # @liquid_type filter
    # @liquid_category array
    # @liquid_summary
    #   Filters an array to include only items with a specific property value.
    # @liquid_description
    #   This requires you to provide both the property name and the associated value.
    # @liquid_syntax array | where: string, string
    # @liquid_return [array[untyped]]
    def where(input, property, target_value = nil)
      ary = InputIterator.new(input, context)

      if ary.empty?
        []
      elsif target_value.nil?
        ary.select do |item|
          item[property]
        rescue TypeError
          raise_property_error(property)
        rescue NoMethodError
          return nil unless item.respond_to?(:[])
          raise
        end
      else
        ary.select do |item|
          item[property] == target_value
        rescue TypeError
          raise_property_error(property)
        rescue NoMethodError
          return nil unless item.respond_to?(:[])
          raise
        end
      end
    end