> ## Documentation Index
> Fetch the complete documentation index at: https://docs.cocartapi.com/llms.txt
> Use this file to discover all available pages before exploring further.

# CoCart Core v5

> These breaking changes improve the core of CoCart and provides better support for these specific features.

<Warning>
  Core v5 is still in development so some feature, filter, hook or ability may change before it's released.
</Warning>

## REST API

<Note>
  The REST API has had small changes that affect the schema and default behaviors of all API. Please review the [API Reference](/api-reference/introduction) and check if an endpoint has been tagged "Updated".
</Note>

* Avatars only return if requested now when using the login endpoint.
* Store API now returns array of CoCart versions installed not just the core version.
* Product meta will **not** return by default. To improve security and prevent *PII* from exposure, meta must now be **whitelisted** instead using the new filter `cocart_products_allowed_meta_keys`.
* Variation data for items is moved above item totals when fetching the cart.
* The quantity parameter when adding an item now accepts both a `numeric` or an `array` value allowing to extend support for other product types that are a container of other grouped products.
* Product Categories changed `image_src` from a single thumbnail to return all image sizes available. Schema updated to match.
* Product reviews was updated to support better query parameters. Affects both API versions. Schema updated to match.
* Feature: [Load Cart from Session](/documentation/learn/load-cart) has been rewritten to support both guest and registered customers.

## Returned Headers

The following returned headers have also been renamed. Better for security reasons.

| Previous Header            | New Header      |
| -------------------------- | --------------- |
| CoCart-API-Cart-Key        | Cart-Key        |
| CoCart-Timestamp           | Timestamp       |
| CoCart-API-Cart-Expiring   | Cart-Expiring   |
| CoCart-API-Cart-Expiration | Cart-Expiration |

## Action Hooks

The following action hooks have changed.

| Action Hook                         | Change                                           |
| ----------------------------------- | ------------------------------------------------ |
| `cocart_item_restored`              | Added the request object as the first parameter. |
| `cocart_item_removed`               | Added the request object as the first parameter. |
| `cocart_item_added_updated_in_cart` | Moved the request object parameter to be first.  |
| `cocart_item_added_to_cart`         | Moved the request object parameter to be first.  |

## Filters

* Filter `cocart_cart_item_quantity` has changed the order of the `$cart_item` and `$item_key` parameter for consistency with other filters.

## Plugin

* The text domain a.k.a the plugin slug, has changed from `cart-rest-api-for-woocommerce` to `cocart-core`. This affects any translations including custom. If you did a custom translation you will need to rename the text domain to match.

* The plugin will deactivate the legacy core version if one is found installed and active. If you try to activate legacy version while the new core version is active it will deactivate. Recommend deleting.

<Tip>
  If you have the `COCART_REMOVE_ALL_DATA` constant set to true. Recommend setting it to false before uninstalling the legacy version from your WordPress dashboard to prevent any issues. Otherwise, use FTP to delete the legacy plugin instead.
</Tip>

## Deprecations

<Tip>
  **Developer Impact**

  If you have extended CoCart or used any public functions within CoCart for your own API endpoints. Please check the deprecated list below.
</Tip>

* The response class `CoCart_Response` is deprecated. New utility response classes have been created for better utilization.
* Function `cocart_prepare_money_response()` is replaced with function `cocart_format_money()`.

The following filters are no longer used:

* `cocart_load_cart_override`
* `cocart_load_cart`
* `cocart_merge_cart_content`
* `cocart_cart_loaded_successful_message`
* `cocart_use_cookie_monster`
* `cocart_filter_request_data`
* `cocart_products_ignore_private_meta_keys`
* `cocart_return_default_response`
* `cocart_{$endpoint}_response`

## For Developers

1. The main cart controller `CoCart_REST_Cart_V2_Controller` for API v2 now extends a new abstract controller `CoCart_REST_Cart_Controller` for the cart.

<Note>
  This allows to better extend the cart API rather than the whole cart controller.
</Note>

2. The following endpoints for Cart API v2: `cart/add-item`, `cart/add-items`, `cart/calculate` now extend `CoCart_REST_Cart_V2_Controller` instead of the Cart API v1 controller.

<Note>
  This allows us to deprecate API v1 in the future. Still working on disconnecting Products API v2 from v1.
</Note>