Cross browser AppSwitch

[AlexP11223]

Added handling of cross-browser AppSwitch (started in non-default browser, then redirected to the default one).

We save the current cart + PayPal order ID into transient before going to PayPal and add the transient key into the return URL, then after returning we retrieve the saved cart and PayPal order, create a WC order and redirect to Pay for order.

The WC order creation is done using the existing WooCommerceOrderCreator, refactored to use CartData instead of the current WC cart.
I had to change the woocommerce_paypal_payments_shipping_callback_woocommerce_order_created hook parameters. I hope it was used only internally 🤔 And renamed it to woocommerce_paypal_payments_woocommerce_order_created_from_cart, so that at least nothing crashes, and because it's not just the shipping callback.

Remaining issues:

• Cross-browser AppSwitch does not work when starting from block checkout because WC redirects to cart if the cart is empty on checkout losing all parameters.
• AppSwitch resume does not work in block cart if PayPal is not the default gateway.

[hmouhtar]

Hi @AlexP11223, thanks for working on this!

I added some comments, and I have a couple of questions:

1. What happens if the EarlyOrderHandler is enabled? Wouldn't we end up with 2 orders?
2. If the user is authenticated, will the order be associated with that user upon returning from AppSwitch on a different browser? configure_customer just sets the current user ID, which will be 0, so it seems that there won't be an association

[AlexP11223]

I think EarlyOrderHandler is not creating anything? It only adds a hook handler to set some meta.

For authenticated users as I understand currently AppSwitch will not trigger at all. But should be possible to save the customer id too. However then WC will ask to log in or enter the email to access the order pay page.

[Narek13]

Thanks for working on this Alex. LGTM

[hmouhtar]

I think EarlyOrderHandler is not creating anything? It only adds a hook handler to set some meta.

For authenticated users as I understand currently AppSwitch will not trigger at all. But should be possible to save the customer id too. However then WC will ask to log in or enter the email to access the order pay page.

@AlexP11223 AppSwitch does trigger for authenticated users. AFAIK PayPal expects the order to be associated with the customer account in the cross browser flow

[github-actions]

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What's included:

• ✅ WordPress (latest)
• ✅ WooCommerce (latest)
• ✅ PayPal Payments plugin v3.0.9-pr3569-17199984186-g2cb2758 (built from this PR)

Login credentials:

• Username: admin
• Password: password

Plugin Details:

• Version: 3.0.9-pr3569-17199984186-g2cb2758
• Commit: 2cb2758
• Artifact: woocommerce-paypal-payments-3.0.9-pr3569-17199984186-g2cb2758

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