django-oscar-datacash 0.2.0

Datacash payment module for django-oscar

This package provides integration with the payment gateway, DataCash. It is designed to integrate seamlessly with the e-commerce framework django-oscar but can be used without using oscar.

Getting started

Installation

From PyPi:

pip install django-oscar-datacash

or from Github:

pip install git+git://github.com/tangentlabs/django-oscar-datacash.git#egg=django-oscar-datacash

Add 'datacash' to INSTALLED_APPS and run:

./manage.py migrate datacash

to create the appropriate database tables.

Configuration

Edit your settings.py to set the following settings:

DATACASH_HOST = 'testserver.datacash.com'
DATACASH_CLIENT = '...'
DATACASH_PASSWORD = '...'
DATACASH_CURRENCY = 'GBP'

There are other settings available (see below). Obviously, you’ll need to specify different settings in your test environment as opposed to your production environment.

Integration into checkout

You’ll need to use a subclass of oscar.apps.checkout.views.PaymentDetailsView within your own checkout views. See oscar’s documentation on how to create a local version of the checkout app.

Override the handle_payment method (which is blank by default) and add your integration code. An example integration might look like:

# myshop.checkout.views
from django.conf import settings

from oscar.apps.checkout.views import PaymentDetails as OscarPaymentDetails
from oscar.apps.payment.utils import Bankcard
from oscar.apps.checkout.forms import BankcardForm
from datacash.facade import Facade

...

class PaymentDetailsView(OscarPaymentDetails):

    def get_context_data(self):
        ...
        # Render a bankcard form
        ctx['bankcard_form'] = BankcardForm()
        ...
        return ctx

    def post(self, request, *args, **kwargs):
        # Check bankcard form is valid
        form = BankcardForm(request.POST)
        if not form.is_valid():
            ctx = self.get_context_data(**kwargs)
            ctx['bankcard_form'] = form
            return self.render_to_response(ctx)

        kwargs['bankcard'] = form.get_bankcard_obj()
        super(PaymentDetailsView, self).post(request, *args, **kwargs)

    def handle_payment(self, order_number, total, **kwargs):
        # Make request to DataCash - if there any problems (eg bankcard
        # not valid / request refused by bank) then an exception would be
        # raised ahd handled) within oscar's PaymentDetails view.
        bankcard = kwargs['bankcard']
        datacash_ref = Facade().pre_authorise(order_number, total, bankcard)

        # Request was successful - record the "payment source".  As this
        # request was a 'pre-auth', we set the 'amount_allocated' - if we had
        # performed an 'auth' request, then we woudl set 'amount_debited'.
        source_type,_ = SourceType.objects.get_or_create(name='Datacash')
        source = Source(source_type=source_type,
                        currency=settings.DATACASH_CURRENCY,
                        amount_allocated=total,
                        reference=datacash_ref)
        self.add_payment_source(source)

Oscar’s view will handle the various exceptions that can get raised. See DataCash’s documentation for further details on the various processing models that are available.

Packages structure

There are two key components:

Gateway

The class datacash.gateway.Gateway provides fine-grained access to the various DataCash APIs, which involve constructing XML requests and decoding XML responses. All calls return a datacash.gateway.Response instance which provides dictionary-like access to the attributes of the response.

Example calls:

from decimal import Decimal as D
from datacash.gateway import Gateway

gateway = Gateway()

# Single stage processing
response = gateway.auth(amount=D('100.00'), currency='GBP',
                        merchant_reference='AA_1234',
                        card_number='4500203021916406',
                        expiry_date='10/14',
                        ccv='345')

response = gateway.refund(amount=D('100.00'), currency='GBP',
                          merchant_reference='AA_1234',
                          card_number='4500203021916406',
                          expiry_date='10/14',
                          ccv='345')

# Two-stage processing (using pre-registered card)
response = gateway.pre(amount=D('50.00'), currency='GBP',
                       previous_txn_reference='3000000088888888')
response = gateway.fulfill(amount=D('50.00'), currency='GBP',
                           txn_reference=response['datacash_reference'])

The gateway object know nothing of Oscar’s classes and can be used in a stand-alone manner.

Facade

The class datacash.facade.Facade wraps the above gateway object and provides a less granular API, as well as saving instances of datacash.models.OrderTransaction to provide an audit trail for Datacash activity.

Settings

• DATACASH_HOST - Host of DataCash server

• DATACASH_CLIENT - Username

• DATACASH_PASSWORD - Password

• DATACASH_CURRENCY - Currency to use for transactions

• DATACASH_USE_CV2AVS - Whether to pass CV2AVS data

• DATACASH_CAPTURE_METHOD - The ‘capture method’ to use. Defaults to ‘ecomm’.

Contributing

To work on django-oscar-datacash, clone the repo, set up a virtualenv and install in develop mode:

python setup.py develop

then install the testing dependencies:

pip install -r requirements.txt

The test suite can then be run using:

./run_tests.py