Adyen Payments - Plugixa Car Parking for WordPress

Adyen PRO is a payment method that sends the customer to Adyen’s Hosted Checkout and brings them back to your site. Customers see it as Online payment (Adyen).

Set it up under Plugixa Car Parking -> Settings -> Adyen. Everything on Payments about the ledger, refunds and booking statuses applies to Adyen payments too.

Setting it up

The Adyen settings: API key, merchant account, theme ID, country, payment methods, test environment, and the Webhook card with its address and HMAC key

You need an Adyen merchant account with payment methods enabled. Adyen opens accounts through its sales team.

Field	Key	Default	Where it comes from
Offer payment by Adyen	`adyen` in `enabled_gateways`	Off	The switch that offers Adyen to customers.
API key	`adyen_api_key`	Empty	Developers -> API credentials, on a web service user. Stored encrypted.
Merchant account	`adyen_merchant_account`	Empty	The merchant account’s name, not the company account’s.
Theme ID	`adyen_theme_id`	Empty	Pay by Link -> Themes: choose Copy theme ID on a theme.
Country code	`adyen_country`	Empty	Two letters, such as `NL`. Adyen uses it to choose the methods to show.
Payment methods	`adyen_methods`	Empty	Adyen method types, such as `scheme`, `ideal`, `bcmc`. Empty shows everything enabled on the account.
Use Adyen’s test environment	`adyen_test_mode`	On	Off takes real money.
Live URL prefix	`adyen_live_prefix`	Empty	Developers -> API URLs in the live Customer Area. Live only.
HMAC key	`adyen_hmac_key`	Empty	From the webhook, below. Stored encrypted.

Adyen is offered to customers only when the switch is on and every field is filled in, including the HMAC key.

Avoid slow methods such as bank transfers. They can settle after the booking’s hold has run out and its space may have been sold to someone else.

The plugin records a payment when Adyen authorises it, and asks Adyen to capture it at once, whatever capture delay the merchant account is set to.

Adding the webhook

Copy the Webhook address shown on the settings screen. It has this form:

https://example.com/wp-json/plugixacarparking/v1/payment/webhook/adyen

In the Customer Area, open Developers -> Webhooks and add a Standard webhook with that address.
Generate its HMAC key and paste it into HMAC key. Adyen shows the key once, and the test and live environments each have their own.
Optionally, enable OFFER_CLOSED on the webhook, to hear about checkouts left to expire.

Event	What the plugin does
`AUTHORISATION`, success	Records the payment, with its type (whole, deposit or balance)
`AUTHORISATION`, failure	Records a Failed row; the booking stays unpaid
`REFUND`, success	Records the refund, once
`REFUND`, failure, `REFUND_FAILED`, `REFUNDED_REVERSED`	Nothing recorded; announced as `refund_failed`
`NOTIFICATION_OF_CHARGEBACK`, `CHARGEBACK`	Nothing recorded; announced as `dispute_opened` and the site is emailed
`CHARGEBACK_REVERSED`	Nothing recorded; announced as `dispute_closed`
`OFFER_CLOSED`	Nothing recorded; announced as `checkout_expired`

“Announced” means the action plugixa_carparking_payment_notice fires, so an add-on or a snippet can email you about it.

Each event’s HMAC signature is checked. An event with a wrong signature, from the other environment or for another merchant account is acknowledged and ignored. An event the plugin accepted but could not write at that moment is answered 503, and Adyen sends it again.

Coming back from the checkout

The customer returns with a session id and result. The plugin confirms these with Adyen, and only for the session it opened for that booking. If the payment is authorised they see Payment received. Otherwise they see Confirming your payment, and the webhook reports how it ended.

Refunds

A refund made from the booking’s Payments panel is sent to Adyen first and recorded with Adyen’s reference. If Adyen refuses the request, nothing is recorded and the error is shown.

Adyen only accepts the request at that point. If it fails later (for example the account has too little money in process), the refund is marked Failed, the booking holds the money again, refund_failed is announced and the site is emailed. Refund again once the problem is solved.

Amounts and currencies

The currency is the booking’s own. Amounts are sent in minor units, following Adyen’s table: for example JPY has no decimals, KWD has three, and ISK and CLP have two.

What is sent to Adyen

The plugin talks to Adyen from your server. There is no Adyen script on your pages.

Sent
API key	To sign in
Amount and currency	The amount due now
Booking reference and payment type	As the payment’s reference
Shopper reference	`pcp-` followed by the booking reference
Country	The country code you set
Customer’s email	For Adyen’s risk checks and 3D Secure
Allowed methods, theme, merchant account	To build the checkout
Return address	On your site

See Privacy and uninstall.

If Pro is removed

The settings and encrypted keys stay, and are live again when Pro is reinstalled. Adyen is no longer offered to customers, and existing rows stay in the ledger with adyen shown as their method.