Eager-Loading Cart images

Question

The cart of Craft Commerce can't really be cached so I try to increase performance by loading product images in the cart via eager-loading.

All tutorials tell me to use the .with(['variantThumb']). But .with can only be used on the craft.entries().section and not on simple loops, I don't understand how to do this.

The stuff in the cart is available via the cart handle:

{% for item in cart.lineItems %}
    {% set cartThumb = item.purchasable.variantThumb.one() %}
    {{ macro.checkoutThumb(cartThumb) }}
{% endfor %}

I don't understand how to use eager-loading in this case.

Answer 1

You can use something like this

{% for item in cart.lineItems %}
    {% set product = craft.products().hasVariant(craft.variants().id(item.purchasableId)).with([['variantThumb', { withTransforms: 'cartThumb'}]]).one() %}
    {% set cartThumb = product.variantThumb[0] %}
    {{ macro.checkoutThumb(cartThumb) }}
{% endfor %}

I am not sure if there will be any significant change on the amount of the queries thought.