Product Compare

Overview

The Compare module lets a shopper collect several products into a comparison list and view them side by side — price, description, rating, SKU, stock, weight, dimensions and shared attributes. A floating toolbar shows what is in the list, and the comparison table can be placed on any page with a shortcode.

It is the free-tier product-experience module: it needs no licence and no external service.

Availability

Item	Value
Module key	compare
Tier	Free core
Entitlement key	compare
Admin tab	compare, under Product Experience
Enabled option	aiowc_module_enabled_compare (off until turned on)
REST namespace	aiowc/v1

Free tier means the compare entitlement is granted by default, so the module can be enabled without a licence key. It is still off until switched on. Enabling it creates the table below and schedules the cleanup job.

Settings

Stored in the bundled option row aiowc_cmp_settings; legacy per-key options aiowc_cmp_<key> are migrated on first read.

API name	Stored key	Default	Meaning
maxProducts	max_products	4	How many products a list may hold. A further add is refused.
compareFields	compare_fields	price, description, rating, sku, stock, weight, dimensions	Fields offered in the comparison table.
showButtonPosition	show_button_position	after_add_to_cart	Where the button goes on a product page (see below).
enableForGuests	enable_for_guests	true	Whether visitors without an account may build a list.
comparePageId	compare_page_id	0	Page the toolbar and buttons link to for the full comparison.

showButtonPosition accepts before_add_to_cart, after_add_to_cart and after_summary. Any other value renders no button on the single-product page; the shop-loop button is added regardless.

enableForGuests is only consulted when the request has neither a signed-in user nor a WooCommerce session id. An ordinary guest with a WooCommerce session passes that check, so turning the setting off does not block most guests in practice.

Admin screen

The Compare tab carries a small settings form with three controls — allow guest comparison, maximum items, and show the button on the shop.

The form posts guest_compare, max_items and show_on_shop. The settings route accepts only maxProducts, compareFields, showButtonPosition, enableForGuests and comparePageId, and ignores anything else, so saves from this screen do not currently change stored settings. The settings route itself works; the screen's field names do not match it.

Lists and identity

A list belongs either to a signed-in user id or to the WooCommerce session id of a guest. getOrCreate resolves the current visitor to a list on every read or write. A merge routine that would move a guest list onto an account exists in the service and the repository, but nothing calls it, so a guest list is not carried over on sign-in.

REST API endpoints

All routes are on aiowc/v1.

Method	Path	Purpose	Required args	Permission
GET	/compare	The current visitor's list.	–	Open read, rate limited
GET	/compare/data	The comparison matrix for the current list.	–	Open read, rate limited
POST	/compare/add	Add a product to the list.	product_id	Public write (nonce, rate limited)
POST	/compare/remove	Remove a product from the list.	product_id	Public write (nonce, rate limited)
DELETE	/compare/clear	Empty the list.	–	Public write (nonce, rate limited)
GET	/compare/overview	Counts for the admin overview.	–	Manage (manage_woocommerce)
GET	/compare/settings	Read the settings above.	–	Manage
PUT / PATCH / POST	/compare/settings	Update the settings above.	–	Manage

Open reads are limited to 120 requests a minute per caller; public writes to 30 a minute and they require a REST nonce.

WooCommerce integration

Frontend handlers are skipped inside wp-admin.

Hook	Priority	What the module does
woocommerce_before_add_to_cart_button	10	Compare button, when showButtonPosition is before_add_to_cart.
woocommerce_after_add_to_cart_button	10	Compare button, when showButtonPosition is after_add_to_cart.
woocommerce_after_single_product_summary	6	Compare button, when showButtonPosition is after_summary.
woocommerce_after_shop_loop_item	16	Compare button in the shop loop.
wp_enqueue_scripts	10	Loads the compare assets.
wp_footer	10	Renders the floating toolbar on product, shop, category, tag and compare pages only.
template_redirect	10	When aiowc-compare is present in the query string, hooks the table into the page content.
the_content	10	Injects the comparison table, in the main query only.

Shortcode

Shortcode	Renders
[aiowc_compare]	The full comparison table.

Database schema

Table	Holds
{prefix}aiowc_compare_lists	One list per user or guest session, with the product ids it holds.

Background jobs

Hook	Interval	Group	Work
aiowc_compare_cleanup	24 hours	aiowc-compare	Deletes guest lists older than 30 days. The 30 days is fixed in the job, not a setting.

Entitlement limits

compare is granted on the free tier, so there is no licence gate in practice and no quota. The one limit a shopper meets is maxProducts, a store setting that defaults to 4.

Health check

The module reports a warning when its table is missing or WooCommerce is inactive, and otherwise reports that it is functioning normally.