Small low-level gopay.com client library

Gopay is a great wide-methods-contained payment gateway made in Czech republic. I guess it's used mainly in Central Europe but can be probably anywhere in Europe.

My code is a very low-level client library I made as part of my implementations. For more information take a look at http://www.gopay.com

There is an official gopay-python client. Why to hell another one?

Yes, that's true. It is written in non-very-pythonistic way. It uses SOAPpy and M2Crypto. And it is 2 years old and it just didn't worked for me. I also use SUDS instead of SOAPpy. And I was happy with PyCrypto.

How it works

It's really low-level. It just helps you to prepare needed objects and sign/decrypt/encrypt messages.

Create payment

gopay = GopayClient("https://testgw.gopay.cz/axis/EPaymentServiceV2?wsdl")
gopay.create_client()
ep_command = gopay.set_ep_command(
			      "your_secret",
			      "target_goid",
			      "13456",
			      "3500",
			      "The best product to buy",
			      "EUR",
			      "en",
			      "eu_cg",
			      "eu_cg,eu_gp_w,eu_paypal,eu_om",
			      "mybestshop.com/gopay/success",
			      "mybestshop.com/gopay/failed",
			      p1="some message I want back",
			      )

ep_command.customerData.email = "some@where.com"
ep_command.customerData.firstName = "John"
ep_command.customerData.lastName = "Smith"
			      
ep_status = gopay.create_payment(ep_command)

if ep_status.result == gopay.CALL_COMPLETED:
    # do your stuff like saving ep_status.paymentSessionId and so...
# ...
message = "|".join([
		    ep_status.targetGoId,
		    ep_status.paymentSessionId,
		    "your secret"
		    ])
    crypto = gopay.create_crypto("your secret")
signature = crypto.encrypt(message)
redirect = "https://gate.gopay.cz/?sessionInfo.paymentSessionId=" + \
        "&sessionInfo.targetGoId=" + target_goid + \
        "&sessionInfo.encryptedSignature=" + signature
# redirect your customer to gate.gopay.cz through http redirect
# ..... 

Get payment info

# this part is quite universal for both success and failed url
# do some stuff to catch GET parameters after customer is redirected
# back from the gateway to your website
gopay = GopayClient("https://gate.gopay.cz/axis/EPaymentServiceV2?wsdl"
crypto = gopay.create_crypto("your secret")

message = "|".join([
		safe_returned_target_goid,
		safe_returned_payment_session_id,
		safe_returned_parent_payment_session_id,
		safe_returned_order_number,
		"your secret",
		])
local_signature = crypto.hash(message)
remote_signature = crypto.decrypt(safe_returned_encrypted_signature)
if local_signature == remote_signature:
    gopay.create_client()
    ep_session_info = client.create_ep_session_info()
ep_session_info.targetGoId = target_goid
ep_session_info.paymentSessionId = payment_session_id
ep_session_info.encryptedSignature = \
	crypto.encrypt(
			"|".join([
				target_goid,
				safe_returned_payment_session_id,
				"your secret",
				])
			)
ep_status = gopay.get_payment_status(ep_session_info)
if ep_status.sessionState == gopay.CANCELED:
	# do some stuff
elif ep_status.sessionState == gopay.TIMEOUTED:
	# do some else
elif ep_status.sessionState == gopay.PAYMENT_TIMEOUTED:
	# ...
else:
	# ....

# this was for failed url. for success you should check
# gopay.PAID and gopay.PAYMENT_PENDING