[FEATURE REQUEST] modify incoming payment metadata

[sidvishnoi]

Feature Request

Ability to modify metadata of an incoming payment after creation.

When creating a payment, we first create an incomingPayment, then a quote for that incoming payment (receiver field). We ask the user to provide some metadata fields (metadata.description) at a later stage, after showing them fee etc.

We cannot include this metadata in incoming payment without creating a new incoming payment/quote now.

Describe the solution you'd like

Ability to modify the incoming payment metadata at a later stage. Modifying during "complete incoming payment" is a good opportunity and easy win. A new endpoint to patch incoming payment would be helpful as well.

As an example, Stripe let's us modify metadata for a paymentIntent at a later stage as well (https://docs.stripe.com/api/payment_intents/update#update_payment_intent-metadata).

Describe alternatives you've considered

Create a new incoming payment and a new quote, with relevant metadata.

Additional context

We found this use case in tools repo, where we ask user for a "payment description" after incoming payment/quote creation.

[mkurapov]

Some of the things dicsussed during 02/07 OP call:

• patch access type (and patch-all)
• final say for what the metadata should contained should be up to the resource server (the ASE)
• Potentially an append-only metadata field, to prevent overlapping keys in an object
• JSON patch is an option, but not sure how ergonomic