python-payer-api 0.1.2
Python package for interacting with the Payer payments API        (http://www.payer.se).
License: MIT

Python Payer API
================

|Build Status| |Coverage Status| |Latest Version|

Python package for interacting with the `Payer <http://payer.se>`__
payments API.

The scope of this module is basically to serialize the data into XML
ready for transmitting to Payer. Given order details, billing details
and callback URLs it will build an XML tree, encode it according to the
Payer specifications and return the encoded data along with the required
key-value pairs in a dict. Payer expects this data in a POST request
using an ``application/x-www-form-urlencoded`` content type.

Generating HTML, providing any type of request handlers or views needed
for a successful payment procedure however, is outside the scope of this
module. Such implementations are encouraged to be realized as
independent modules, in relation to the frameworks, webshop modules etc.
that you may be using. One such example is
`django-shop-payer-backend <https://github.com/dessibelle/django-shop-payer-backend>`__
for which python-payer-api was initially developed.

Installation
------------

::

    pip install python-payer-api

Basic usage
-----------

.. code:: python

    from payer_api import PAYMENT_METHOD_CARD, PAYMENT_METHOD_BANK, PAYMENT_METHOD_PHONE, PAYMENT_METHOD_INVOICE
    from payer_api.postapi import PayerPostAPI
    from payer_api.order import (
        PayerProcessingControl,
        PayerBuyerDetails,
        PayerOrderItem,
        PayerOrder,
    )

    api = PayerPostAPI(
        agent_id="AGENT_ID",
        key_1="6866ef97a972ba3a2c6ff8bb2812981054770162",
        key_2="1388ac756f07b0dda2961436ba8596c7b7995e94",
        payment_methods=[PAYMENT_METHOD_CARD, PAYMENT_METHOD_BANK, PAYMENT_METHOD_PHONE, PAYMENT_METHOD_INVOICE]
    )


    processing_control = PayerProcessingControl(
        success_redirect_url="http://localhost/webshop/thankyou/",
        authorize_notification_url="http://localhost/webshop/auth/",
        settle_notification_url="http://localhost/webshop/settle/",
        redirect_back_to_shop_url="http://localhost/webshop/",
    )

    order = PayerOrder(
        order_id="123456",
        buyer_details=PayerBuyerDetails(
            first_name="John",
            last_name="Doe",
            address_line_1="1234 Main Street",
            postal_code="12345",
            city="Anywhere",
            phone_mobile="012345678",
            email="john.doe@host.com",
        ),
        order_items=[
            PayerOrderItem(
                description='A product',
                price_including_vat=123.50,
                vat_percentage=25,
                quantity=4,
            ),
            PayerOrderItem(
                description='Another product',
                price_including_vat=123.0,
                vat_percentage=12.5,
                quantity=2,
            ),
        ],
        info_lines=[
            "Shipping with 5 work days",
            "Additional line of order info",
        ]
    )

    api.set_order(order)
    api.set_processing_control(processing_control)

    print api.get_post_data()

Payment Process
---------------

The main flow of the payment process is as follows:

1. Initialize a ``PayerPostAPI`` object using the Agent ID, Key 1 and
   Key 2 values supplied by Payer. Optinally set ``test_mode`` and
   ``debug_mode`` and add a list of ``payment_methods``.
2. Create a ``PayerProcessingControl`` object and add it to your API
   object using the ``set_processing_control()`` method. This object
   holds four URL's that your site has to provide. They are:
    
   ``success_redirect_url``: A "thank you" URL, displayed after
   completed purchase
   ``authorize_notification_url``: A callback URL, described below,
   called when orders are authorized.
   ``settle_notification_url``: A callback URL, described below, called
   when orders are payed.
   ``redirect_back_to_shop_url``: A "cancel" or "back to shop" URL.
    
3. Create a ``PayerOrder`` object (including ``PayerBuyerDetails`` and
   ``PayerOrderItem`` objects) and add it to your API object using the
   ``set_order()`` method.
4. You can now call ``api.get_post_data()`` for a dict of the query
   parameters Payer expects. Add them as ``<input type="hidden">``
   elements in a ``<form>`` element with method ``POST`` and action
   ``api.get_post_url()`` and have the user submit the form (i.e. needs
   to happen in front-end).
5. Payer will parse your order, and once the payment has been completed
   Payer will perform a GET request to your callback URL's - the
   ``authorize_notification_url`` URL, and depending on payment method
   (direct / invoice) call the ``settle_notification_url`` URL. You will
   want to implement a view or URL handler that listens on these URL's,
   for which you call the ``validate_callback_ip()`` and
   ``validate_callback_url()`` methods on PayerPostAPI. A couple of
   query parameters will be appended to the callback URL's, from which
   you can extract the Order ID, selected payment method, payment ID
   etc. The complete list of query paramters are:
    
   ``order_id``, ``payer_callback_type``, ``payer_testmode``,
   ``payer_payment_type``, ``payer_added_fee``,
   ``payer_merchant_reference_id``, ``payer_payment_id``,
   ``payread_payment_id``.
    
   Depending on the validity of the requests, your view should return
   either ``TRUE`` or ``FALSE`` using a ``text/plain`` content type.
6. Once Payer has performed its auth and settle validation it will
   redirect the user the the ``success_redirect_url`` URL.

.. |Build Status| image:: https://travis-ci.org/dessibelle/python-payer-api.svg?branch=master
   :target: https://travis-ci.org/dessibelle/python-payer-api
.. |Coverage Status| image:: https://coveralls.io/repos/dessibelle/python-payer-api/badge.svg?branch=master
   :target: https://coveralls.io/r/dessibelle/python-payer-api?branch=master
.. |Latest Version| image:: https://pypip.in/version/python-payer-api/badge.svg?style=flat
   :target: https://pypi.python.org/pypi/python-payer-api/