[ADD] payment_acquirers/adyen: add doc configuration of Adyen

Following a technical task regarding the migration of the Adyen hosted
payment page integration to Adyen PayByLink, some new parameters have
been introduced and some have been removed.

This new addition to the documentation will help users configure their
acquirer.

task-2802921

closes odoo/documentation#1737

Signed-off-by: Antoine Vandevenne (anv) <anv@odoo.com>

content/applications/finance/payment_acquirers.rst

@@ -8,6 +8,7 @@ Payment Acquirers (Credit Cards, Online Payment)
    :titlesonly:
 
    payment_acquirers/wire_transfer
+   payment_acquirers/adyen
    payment_acquirers/authorize
    payment_acquirers/paypal
    payment_acquirers/stripe
@@ -63,7 +64,8 @@ Online Payment Providers
 |                                     | Redirection to       | Payment   | Save Cards | Capture Amount  |
 |                                     | the acquirer website | from Odoo |            | Manually        |
 +=====================================+======================+===========+============+=================+
-| Adyen                               | ✔                    |           |            |                 |
+| :doc:`Adyen                         | ✔                    |           |            |                 |
+| <payment_acquirers/adyen>`          |                      |           |            |                 |
 +-------------------------------------+----------------------+-----------+------------+-----------------+
 | Alipay                              | ✔                    |           |            |                 |
 +-------------------------------------+----------------------+-----------+------------+-----------------+

content/applications/finance/payment_acquirers/adyen.rst

@@ -0,0 +1,88 @@
+:show-content:
+
+=====
+Adyen
+=====
+
+.. toctree::
+   :titlesonly:
+
+   adyen/install_pay_by_link_patch
+
+`Adyen <https://www.adyen.com/>`_ is a Dutch company that offers several online payment
+possibilities.
+
+.. seealso::
+   - :doc:`adyen/install_pay_by_link_patch`
+   - :ref:`payment_acquirers/add_new`
+   - :doc:`../payment_acquirers`
+
+Configuration
+=============
+
+Credentials tab
+---------------
+
+Odoo needs your **API Credentials** to connect with your Adyen account, which comprise:
+
+- **Merchant Account**: The code of the merchant account to use with Adyen.
+- :ref:`API Key <adyen/api_key>`: The API key of the webservice user.
+- :ref:`HMAC Key <adyen/hmac_key>`: The HMAC key of the webhook.
+- :ref:`Checkout API URL <adyen/urls>`: The base URL for the Checkout API endpoints.
+
+You can copy your credentials from your Adyen account, and paste them in the related fields under
+the **Credentials** tab.
+
+.. important::
+   If you are trying Adyen as a test, with a *test account*, change the **State** to *Test Mode*. We
+   recommend doing this on a test Odoo database, rather than on your main database.
+
+.. _adyen/api_key:
+
+API Key
+~~~~~~~
+
+In order to retrieve the API Key, log into your Adyen account, go to
+:menuselection:`Developers --> API Credentials`.
+- If you already have an API user, open it.
+- If you don't have an API user yet, click on **Create new credential**.
+Go to :menuselection:`Authentication` and get or generate your **API Key**. Be careful to copy your
+API key as you'll not be allowed to get it later without generating a new one.
+
+.. _adyen/hmac_key:
+
+HMAC key
+~~~~~~~~
+
+In order to retrieve the HMAC Key, you'll need to configure a `Standard Notification` webhook. For
+this, log into your Adyen account then go to :menuselection:`Developers --> Webhooks --> Add webhook
+--> Add Standard notification`.
+
+.. image:: adyen/add-webhook.png
+   :align: center
+   :alt: Configure a webhook.
+
+There, in :menuselection:`General --> Server Configuration --> URL`, enter your server address
+followed by `/payment/adyen/notification` and in :menuselection:`General --> Server Configuration
+--> Method`, select `HTTP Post`.
+
+.. image:: adyen/webhook-url.png
+   :align: center
+   :alt: Enter the notification URL.
+
+Then continue in :menuselection:`Security --> HMAC Key --> Generate new HMAC key`. Be
+careful to copy it as you'll not be allowed to get it later without generating a new one.
+
+You have to save the webhook to finalize its creation.
+
+.. _adyen/urls:
+
+URLs
+~~~~
+
+To retrieve the URLs, log into your Adyen account, go to :menuselection:`Developers --> API URLs`.
+Pick one of the URLs listed next to **Checkout API** as your **Checkout API URL**.
+
+.. image:: adyen/api-urls.png
+   :align: center
+   :alt: Get the links for the different API.

content/applications/finance/payment_acquirers/adyen/install_pay_by_link_patch.rst

@@ -0,0 +1,55 @@
+===================================
+Install the Adyen Pay by Link Patch
+===================================
+
+Starting October 2022, due to `Adyen deprecating their Hosted Payment Page solution
+<https://docs.adyen.com/online-payments/classic-integrations/hosted-payment-pages/deprecation>`_,
+:doc:`Adyen <../adyen>` needs to be updated to continue accepting payments.
+
+.. note::
+   If your Odoo database is created after the update was released, the update module is installed
+   automatically. To check if this module is already installed, go to :guilabel:`Apps`, remove the
+   ``Apps`` filter and search for ``Adyen``. If the module :guilabel:`Adyen Payment
+   Acquirer/Pay by Link Patch` is present and marked as installed, your Odoo database is already
+   up-to-date and you can proceed with the configuration step of :doc:`Adyen <../adyen>`.
+
+Update Odoo to the latest release
+=================================
+
+The new integration is made available through a new Odoo module; to be able to install it, you must
+make sure that your Odoo source code is up-to-date.
+
+If you use Odoo on Odoo.com or Odoo.sh platform, your code is already up-to-date and
+you can proceed to the next step.
+
+If you use Odoo with an on-premise setup or through a partner, then you must update
+your installation as detailed in
+:doc:`this documentation page </administration/maintain/update>`
+or by contacting your integrating partner.
+
+Update the list of available modules
+====================================
+
+New modules must be *discovered* by your Odoo instance to be available in the **Apps**
+menu.
+
+To do so, activate the :ref:`developer mode <developer-mode>`, and go to :menuselection:`Apps -->
+Update Apps List`. A wizard will ask for confirmation.
+
+Install the Adyen Payment Acquirer/Pay by Link Patch
+====================================================
+
+.. warning::
+   You should never install new modules in your production database without first testing them in a
+   duplicate or staging environment. For Odoo.com customers, a duplicate database can be created
+   from the database management page. For Odoo.sh users, you should use a staging or duplicate
+   database. For on-premise users, you should use a staging environment---contact your integrating
+   partner for more information regarding how to test a new module in your particular setup.
+
+The module should now be available in your :guilabel:`Apps` menu. Remove the ``Apps`` filter and
+search for ``Adyen``; the module :guilabel:`Adyen Payment Acquirer/Pay by Link Patch` should be
+available for installation. If you cannot find the module after having updated the list of available
+modules, it means your Odoo source code is not up-to-date; refer to step one of this page.
+
+Once the module is installed, configure your acquirer following the instructions on the
+:doc:`Adyen <../adyen>` page.