Welcome to python-redsys!

A simple, clean and less dependant client to handle payments through RedSys platform (previously known as Sermepa) using the two types of connection defined by the platform: direct connection (or webservice) and redirect connection or (secure method).

The purpose of this library is just provide a normalized interface between RedSys and other applications.

About `RedirectClient`

Although redirect connection depends on a webserver to resolve the communication step, the RedirectClient provided in this library does not assumes any kind of procedure to resolve that step; it merely prepares the necessary parameters to make a request and handle the corresponding response parameters. That's what less dependant means.

If you are intend to use this library with django, take a look at <https://github.com/ddiazpinto/django-redsys>. Django-redsys uses this library and extends it to resolve all the communication step. Unfortunately it is not documented at all but if you need some help, let me know submitting an issue.

Example using redirect connection

1. Instantiate the redirect client

from decimal import Decimal as D, ROUND_HALF_UP
from redsys import currencies, languages, parameters, transactions
from redsys.client import RedirectClient

secret_key = u'123456789abcdef'
sandbox = False
client = RedirectClient(secret_key, sandbox)

2. Create a request

request = client.create_request()

3. Set up the request parameters

request.merchant_code = u'100000001'
request.terminal = u'1'
request.transaction_type = transactions.STANDARD_PAYMENT
request.currency = currencies.EUR
request.order = u'000000001'
# The amount must be defined as decimal and pre-formated with only two decimals
request.amount = D('10.56489').quantize(D('.01'), ROUND_HALF_UP)
request.merchant_data = 'merchant data for tracking purpose like order_id, session_key, ...'
request.merchant_name = "Example Commerce"
request.titular = "Example Ltd."
request.product_description = "Products of Example Commerce"
request.merchant_url = "https://example.com/redsys/response"

4. Prepare the request

This method returns a dict with the necessary post parameters that are needed during the communication step.

args = client.prepare_request(request)

5. Communication step

Redirect the user-agent to the corresponding RedSys's endpoint using the post parameters given in the previous step.

After the payment process is finish, RedSys will respond making a request to the merchant_url defined in the step 3.

6. Create and check the response

Create the response object using the received parameters from RedSys. The method create_response() throws a ValueError in case of the received signature does not be equal to the calculated one using the given merchant_parameters. This normally means that the response is not comming from RedSys or that has been compromised.

signature = "YqFenHc2HpB273l8c995...."
merchant_parameters = "AndvIh66VZdkC5TG3nYL5j4XfCnFFbo3VkOu9TAeTs58fxddgc..."
signature_version = "HMAC_SHA256_V1"
response = client.create_response(signature, merchant_parameters, signature_version)
if response.is_paid():
    # Do the corresponding actions after a successful payment
else:
    # Do the corresponding actions after a failed payment
    raise Exception(response.response, response.message)

Methods for checking the response:

According to the RedSys documentation:

• `response.is_paid(): Returns True` if the response code is between 0 and 99 (both included).
• `response.is_canceled(): Returns True` if the response code is 400.
• `response.is_refunded(): Returns True` if the response code is 900.
• `response.is_authorized(): Returns True` if the response is paid, refunded or canceled.

Also, you can directly access the code or the message defined in RedSys documentation using response.response_code or response.response_message.

Example using direct connection or webservice

This connection method is not implemented yet.

Contributions

Please, feel free to send any contribution that maintains the less dependant philosophy.