[ADD] pos: adyen payment terminal

Task ID: 2808584
Do not Forward port r+

closes odoo/documentation#2017

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

content/applications/sales/point_of_sale/payment.rst

@@ -7,6 +7,7 @@ Payment Terminals
 .. toctree::
    :titlesonly:
 
+   payment/adyen
    payment/ingenico
    payment/vantiv
    payment/six

content/applications/sales/point_of_sale/payment/adyen.rst

@@ -0,0 +1,77 @@
+=====
+Adyen
+=====
+
+Connecting an **Adyen payment terminal** allows you to offer a fluid payment flow to your customers
+and ease the work of your cashiers.
+
+Configuration
+=============
+
+Start by creating your Adyen account on `Adyen's website <https://www.adyen.com/>`_. Then, board
+your terminal following the steps described on your terminal's screen.
+
+.. seealso::
+   - `Adyen Docs - Payment terminal quickstart guides
+     <https://docs.adyen.com/point-of-sale/user-manuals>`_.
+
+Configure the payment method
+----------------------------
+
+First, go to :menuselection:`Point of Sale --> Configuration --> Settings --> Payment Terminals`,
+and enable :guilabel:`Adyen`.
+Then, go to :menuselection:`Configuration --> Payment Methods` and create a new payment method.
+Select :guilabel:`Adyen` in the :guilabel:`Use a Payment Terminal` field.
+
+.. note::
+   The selected journal **must** be a bank journal for the :guilabel:`Use a payment terminal` field
+   to appear.
+
+Finally, fill the mandatory fields with an :guilabel:`Adyen API key`, and an :guilabel:`Adyen
+Terminal Identifier`.
+
+Generate an Adyen API key
+~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The **Adyen API key** is a key used to authenticate your requests. To generate an API key, go to
+your **Adyen account**.
+
+Then, go to :menuselection:`Developers --> API credentials`. Create a new credential or click on an
+existing one.
+
+Click on :guilabel:`Generate an API key` and copy-paste that key onto the Odoo mandatory field.
+
+.. seealso::
+   - `Adyen Docs - API credentials
+     <https://docs.adyen.com/development-resources/api-credentials#generate-api-key>`_.
+
+Locate the Adyen terminal identifier
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The **Adyen Terminal Identifier** is your terminal's serial number, which is used to identify the
+hardware.
+
+To find this number, go to your **Adyen account**. Then, go to :menuselection:`Point of Sale
+--> Terminals`, select the terminal to link, and copy-paste its serial number onto the Odoo
+mandatory field.
+
+Add a new payment method
+========================
+
+To add a new **payment method** to a point of sale, go to :menuselection:`Point of Sale -->
+Configuration --> Point of Sale`. Then, select the POS and go to :menuselection:`Payments -->
+Payment Methods`, and add your new method for Adyen.
+
+Pay with a payment terminal
+===========================
+
+When processing a payment, select :guilabel:`Adyen` as the payment method. Check the amount and
+click on :guilabel:`Send`. Once the payment is successful, the status changes to :guilabel:`Payment
+Successful`.
+
+.. note::
+   - | In case of connexion issues between Odoo and the payment terminal, force the payment by
+       clicking on :guilabel:`Force Done`, which allows you to validate the order.
+     | This option is only available after receiving an error message informing you that the
+       connection failed.
+   - To cancel the payment request, click on :guilabel:`cancel`.

content/applications/sales/point_of_sale/payment/ingenico.rst

@@ -2,8 +2,8 @@
 Ingenico
 ========
 
-Connecting a payment terminal allows you to offer a fluid payment flow
+Connecting a payment terminal allows you to offer a fluid payment flow to your customers and ease
-to your customers and ease the work of your cashiers.
+the work of your cashiers.
 
 Please note that Ingenico is currently only available for customers in the
 Benelux.

content/applications/sales/point_of_sale/payment/six.rst

@@ -2,8 +2,8 @@
 SIX
 ====
 
-Connecting a SIX payment terminal allows you to offer a fluid
+Connecting a SIX payment terminal allows you to offer a fluid payment flow to your customers and
-payment flow to your customers and ease the work of your cashiers.
+ease the work of your cashiers.
 
 .. warning::
    Even though Worldline has recently acquired SIX Payment Services and both

content/applications/sales/point_of_sale/payment/vantiv.rst

@@ -2,8 +2,8 @@
 Vantiv
 ======
 
-Connecting a Vantiv payment terminal allows you to offer a fluid payment
+Connecting a Vantiv payment terminal allows you to offer a fluid payment flow to your customers and
-flow to your customers and ease the work of your cashiers.
+ease the work of your cashiers.
 
 .. note::
    Please note MercuryPay only operates with US and Canadian banks, making