PayPal PayFlow with MVC3 ASP.NET

Question

Hi I was using this article

http://www.codeproject.com/Articles/152280/Online-Credit-Card-Transaction-in-ASP-NET-Using-Pa?msg=3753796#xx3753796xx

to understand the PayFlow Transaction Process and how to develope it.

After doing some successful tests from the example, I had some doubts about how I should be developing it for the release version.

1.- I'm planning to use the SDK methods and NVP call just like in the example for the release version. However, I don't know if I should be using something more like secure certificates or services call (I tried calling the wsdl service from .Net Wizard but I couldnt find any service that had to do with PayFlow Transactions).

2.- Also, in the PDF:

https://cms.paypal.com/cms_content/US/en_US/files/developer/PP_PayflowPro_Guide.pdf

There are some examples, like the one in page 29, that state:

//Typical Sale Transaction Parameter String
//The following is a typical PARMLIST string passed in a Sale transaction.

"TRXTYPE=S&TENDER=C&USER=SuperUser&PWD=SuperUserPassword&VENDOR=SuperUser&PA
RTNER=PayPal&ACCT=5105105105105100&EXPDATE=1209&CVV2=123&AMT=99.00&FIRSTNAM
E=John&LASTNAME=Smith&STREET=123 Main St.&CITY=San
Jose&STATE=CA&ZIP=12345&COMMENT1=Reservation&INVNUM=1234567890&PONUM=C12345
&CVV2=567&VERBOSITY=MEDIUM"

//Note that, besides the required parameters that you pass in a Sale transaction, this string
//includes other typical parameters. The COMMENT1 (and COMMENT2) fields help to track
//transaction information. The customer’s street address (STREET) and zip should be passed to 
//use address verification service. CVV2 is needed for card security code validation.

What I dont understand in that example is why is using the CCV2 parameter twice. Also, I dont know what the INVNUM and PONUM parameters mean. Furthermore, I know the test will be successful if I dont pass the CCV2 (security code) parameter and the adress parameters, but arent these mandatory? It gets me a bit confused, since for the DirectPayment Service, they are.

3.- In the PDF, there is a section called "Submitting Purchasing Card Level 2 and Level 3 Transactions" in page 99. In page 100, it says:

//Level 2 and Level 3 data is generally considered non-financial data. Lack of adequate data
//may cause a transaction to be downgraded.PayPal generally requires up to Level 2 information in 
//an Authorization transaction followed by additional Level 3 data in the associated
//Delayed Capture transaction. A Sale transaction should include all Level 3 data 
//since it is authorized and later settled.

Does this means that I "Need" to use more parameters than the required ones for a Sale transaction; otherwise, the transaction might be downgraded?

Answer 1

1) PayPal provides PayFlow documentation that covers all of that. You'll basically need to send the same login credentials used at manager.paypal.com along with your API requests.

2) I think that's just a mistake that they have the CVV2 parameter included twice. You only want to include it once. The documentation I linked to before will cover what all the request parameters mean, but the INVNUM is what you can use to track your own invoices within the PayFlow/Paypal system. PONUM is similar, but would be a PO number instead of an invoice number. You could search on these values in the future if you need to find them in the PayPal system.

With both PayFlow and Direct Payment, the requirement of CVV2 and a matching billing address depends on your account's Fraud Filter settings. If you've set it up to require them then you'd get an error without it. If it's setup to accept failures/mis-matches then it'll do so accordingly.

3) No, you won't need to worry about this.