2021-10-13 - Refund handling

INFO

This document represents an architecture decision record (ADR) and has been mirrored from the ADR section in our Shopware 6 repository. You can find the original version here

Context

Shopware offers no way of unified refund handling. This results in every payment extension either implementing it themselves or not at all.

Decision

We want to implement the following structure to offer a unified refund handling for all extension types.

New refund data structure

A payment extension will need to persist its actual captures to use the refund handling. Those captures are bound to a specific OrderTransaction. The capture has an amount, allows saving an external reference.

OrderTransactionCapture

A capture is directly associated with a transaction. This relation is n order_transaction_captures to 1 order_transaction.

Database table

Type	Field name	References
BINARY(16)	id
BINARY(16)	transaction_id	order_transaction.id
BINARY(16)	state_id	state_machine_state.id
VARCHAR(255) NULL	external_reference
LONGTEXT	amount
LONGTEXT NULL	custom_fields

Entity

Type	Property name
string	id
string	transactionId
string	stateId
string/null	externalReference
float	totalAmount
CalculatedPrice	amount
array/null	customFields
OrderTransactionEntity/null	transaction
StateMachineStateEntity/null	stateMachineState
OrderTransactionRefundCollection/null	refunds

OrderTransactionCaptureRefund

A refund is directly associated with a capture. This relation is n order_transaction_capture_refunds to 1 order_transaction_capture.

Database table

Type	Field name	References
BINARY(16)	id
BINARY(16)	capture_id	order_transaction_capture.id
BINARY(16)	state_id	state_machine_state.id
VARCHAR(255) NULL	reason
LONGTEXT	amount
LONGTEXT NULL	custom_fields
VARCHAR(255) NULL	external_reference

Entity

Type	Property name
string	id
string	captureId
string	stateId
string/null	externalReference
string/null	reason
float	totalAmount
CalculatedPrice	amount
array/null	customFields
StateMachineStateEntity/null	stateMachineState
OrderTransactionCaptureEntity/null	transactionCapture
OrderTransactionCaptureRefundPositionCollection/null	positions

OrderTransactionCaptureRefundPosition

Refund positions are optional and only there if a refund is position-specific. They relate n order_transaction_capture_refund_positions to 1 order_transaction_capture_refund.

Database table

Type	Field name	References
BINARY(16)	id
BINARY(16)	refund_id	order_transaction_capture_refund.id
BINARY(16)	line_item_id	order_line_item.id
INT(11)	quantity
VARCHAR(255) NULL	reason
LONGTEXT	refund_amount
LONGTEXT NULL	custom_fields

Entity

Type	Property name
string	id
string	refundId
string	lineItemId
string/null	reason
int	quantity
float	refundPrice
CalculatedPrice	refundAmount
array/null	customFields
OrderLineItemEntity/null	lineItem
OrderTransactionCaptureRefundEntity/null	orderTransactionCaptureRefund

Changes to existing entities

PaymentMethod

• Add refundHandlingEnabled computed field if payment method handler implements RefundHandlerInterface

OrderTransaction

• Add OneToManyAssociation OrderTransactionCaptureCollection captures

OrderLineItem

• Add OneToManyAssociation OrderTransactionCaptureRefundPositionCollection|null refundPositions

State machine

Add 2 new state machines for OrderTransactionCapture and OrderTransactionCaptureRefund.

OrderTransactionCapture

We want to add the following states to a new order_transaction_capture.state state machine:

• pending
• completed
• failed

OrderTransactionCaptureRefund

We want to add the following states to a new order_transaction_capture_refund.state state machine:

• open
• in_progress
• cancelled
• failed
• completed

PaymentRefundHandlerInterface

Add an interface as outlined below:

public function refund(string $orderRefundId, Context $context): void;

PaymentRefundProcessor

The PaymentRefundProcessor gets triggered via a corresponding Admin-API action and contains the method processRefund as outlined below:

public function processRefund(string $refundId, Context $context): Response;

Apps

The whole refund handling should be available for apps and plugins. The following changes are required to allow apps to handle refunds.

\Shopware\Core\Framework\App\Manifest\Xml\PaymentMethod

Add refundUrl to the manifest PaymentMethod. Also change the xsd accordingly.

AppRefundHandler

Add an AppRefundHandler, which assembles payloads and talks to the app refund endpoint.

Captures and apps

Captures are written over the Admin-API endpoint.