Commerce Line Item Taxonomy Reference Filtered by Product Selection

Question

Here's the scenario:

• I'm selling furniture. I have a chair we'll call Mission Chair.
• The Mission Chair comes in oak or maple, both are priced differently. I have a field in my product
• I have a product display created which references these 2 products
• Customers need to choose 1 of 5 stain colors, but each type of wood has 5 different choices (and they're not the same choices)
• The stain choice is required, but does not affect the price.

In my Product Variation Type, I have a term reference field which is referencing a Wood Species vocabulary.

I assume I would create a term reference field on the line item type where they would make the stain color choice. What I need to figure out is how do I do some kind of contextual filter to only show the stains available for the chosen wood species? (which is a taxonomy term on the chosen product - not the display, the product variation)

Should the stains be child terms in the same vocabulary as the wood species, or should it be a separate vocabulary with an additional term field that references a specific wood species (taxonomy reference, the same vocabulary the product variation uses) for each stain color term, and then filter on that somehow?

Answer 1

You have two basic approaches you can use: either treat the stain color as a customization or treat it as a second attribute. Which you pick depends on a little on your backend process needs and the experience you want to provide.

If you use a second attribute and have a product variation for each stain in each wood, Commerce's default add to cart form should provide the user experience you are describing. You might find it helpful to take a look at this tutorial.

If you want to treat stain as a customization you'll likely want a couple extra modules -- in particular Commerce Customizable Product. Commerce Guys have a tutorial covering that scenario.