Classic ASP paypal integration with express checkout - paypal

Question

I have a fully working Classic ASP paypal integration (yay!)
I set up my variables and call the express checkout like this:
paymentAmount = RS_OrderHeader01("PaymentAmount")
currencyCodeType = "GBP"
paymentType = "Sale"
solutionType = "Mark"
OrderDescription = "My order description"
returnURL = "http://www.myurl.co.uk/transactioncomplete.asp"
cancelURL = "http://www.myurl.co.uk/transactioncancelled.asp"
Set resArray = CallShortcutExpressCheckout (paymentAmount, currencyCodeType, paymentType, returnURL, cancelURL)
That all works fine apart from the fact that there is no description being passed across. I would also like to add individual items from my basket to the final transaction in paypal.
The integration I am using is from a download from the Paypal site that hinges around this 'include' file:
<%
' ===================================================
' PayPal API Include file
'
' Defines all the global variables and the wrapper functions
'-----------------------------------------------------------
Dim gv_APIEndpoint
Dim gv_APIUserName
Dim gv_APIPassword
Dim gv_APISignature
Dim gv_Version
Dim gv_BNCode
Dim gv_ProxyServer
Dim gv_ProxyServerPort
Dim gv_Proxy
'----------------------------------------------------------------------------------
' Authentication Credentials for making the call to the server
'----------------------------------------------------------------------------------
SandboxFlag = true
'------------------------------------
' PayPal API Credentials
' Replace <API_USERNAME> with your API Username
' Replace <API_PASSWORD> with your API Password
' Replace <API_SIGNATURE> with your Signature
'------------------------------------
gv_APIUserName = "myusername"
gv_APIPassword = "1404738820"
gv_APISignature = "AFcWxV21CRCpSSRl31AuDrEW4a9MiULwvS8UDzCPvE28G8"
'-----------------------------------------------------
' The BN Code only applicable for partners
'----------------------------------------------------
gv_BNCode = "PP-ECWizard"
'----------------------------------------------------------------------
' Define the PayPal URLs.
' This is the URL that the buyer is first sent to do authorize payment with their paypal account
' change the URL depending if you are testing on the sandbox
' or going to the live PayPal site
'
' For the sandbox, the URL is https://www.sandbox.paypal.com/webscr&cmd=_express-checkout&token=
' For the live site, the URL is https://www.paypal.com/webscr&cmd=_express-checkout&token=
'------------------------------------------------------------------------
if SandboxFlag = true Then
gv_APIEndpoint = "https://api-3t.sandbox.paypal.com/nvp"
PAYPAL_URL = "https://www.sandbox.paypal.com/webscr?cmd=_express-checkout&token="
Else
gv_APIEndpoint = "https://api-3t.paypal.com/nvp"
PAYPAL_URL = "https://www.paypal.com/cgi-bin/webscr?cmd=_express-checkout&token="
End If
gv_Version = "93"
'WinObjHttp Request proxy settings.
gv_ProxyServer = "127.0.0.1"
gv_ProxyServerPort = "808"
gv_Proxy = 2 'setting for proxy activation
gv_UseProxy = False
'-------------------------------------------------------------------------------------------------------------------------------------------
' Purpose: Prepares the parameters for the SetExpressCheckout API Call.
' Inputs:
' paymentAmount: Total value of the shopping cart
' currencyCodeType: Currency code value the PayPal API
' paymentType: PaymentType has to be one of the following values: Sale or Order or Authorization
' returnURL: The page where buyers return to after they are done with the payment review on PayPal
' cancelURL: The page where buyers return to when they cancel the payment review on PayPal
' Returns:
' The NVP Collection object of the SetExpressCheckout call Response.
'--------------------------------------------------------------------------------------------------------------------------------------------
Function CallShortcutExpressCheckout( paymentAmount, currencyCodeType, paymentType, returnURL, cancelURL)
'------------------------------------------------------------------------------------------------------------------------------------
' Construct the parameter string that describes the SetExpressCheckout API call in the shortcut implementation
'------------------------------------------------------------------------------------------------------------------------------------
nvpstr = "&" & Server.URLEncode("PAYMENTREQUEST_0_AMT") & "=" & Server.URLEncode(paymentAmount) & _
"&" & Server.URLEncode("PAYMENTREQUEST_0_PAYMENTACTION")&"=" & Server.URLEncode(paymentType) & _
"&" & Server.URLEncode("RETURNURL") & "=" & Server.URLEncode(returnURL) & _
"&" & Server.URLEncode("CANCELURL") & "=" & Server.URLEncode(cancelURL) & _
"&" & server.UrlEncode("PAYMENTREQUEST_0_CURRENCYCODE") & "=" & Server.URLEncode(currencyCodeType)
SESSION("currencyCodeType") = currencyCodeType
SESSION("PaymentType") = paymentType
'---------------------------------------------------------------------------------------------------------------
' Make the API call to PayPal
' If the API call succeded, then redirect the buyer to PayPal to begin to authorize payment.
' If an error occured, show the resulting errors
'---------------------------------------------------------------------------------------------------------------
Set resArray = hash_call("SetExpressCheckout",nvpstr)
ack = UCase(resArray("ACK"))
If ack="SUCCESS" Then
' Save the token parameter in the Session
SESSION("token") = resArray("TOKEN")
End If
set CallShortcutExpressCheckout = resArray
End Function
'-------------------------------------------------------------------------------------------------------------------------------------------
' Purpose: Prepares the parameters for the SetExpressCheckout API Call.
' Inputs:
' paymentAmount: Total value of the shopping cart
' currencyCodeType: Currency code value the PayPal API
' paymentType: paymentType has to be one of the following values: Sale or Order or Authorization
' returnURL: the page where buyers return to after they are done with the payment review on PayPal
' cancelURL: the page where buyers return to when they cancel the payment review on PayPal
' shipToName: the Ship to name entered on the merchant's site
' shipToStreet: the Ship to Street entered on the merchant's site
' shipToCity: the Ship to City entered on the merchant's site
' shipToState: the Ship to State entered on the merchant's site
' shipToCountryCode: the Code for Ship to Country entered on the merchant's site
' shipToZip: the Ship to ZipCode entered on the merchant's site
' shipToStreet2: the Ship to Street2 entered on the merchant's site
' phoneNum: the phoneNum entered on the merchant's site
' Returns:
' The NVP Collection object of the SetExpressCheckout call Response.
'--------------------------------------------------------------------------------------------------------------------------------------------
Function CallMarkExpressCheckout(paymentAmount, currencyCodeType, paymentType, returnURL, cancelURL, shipToName, shipToStreet, shipToCity, shipToState, shipToCountryCode, shipToZip, shipToStreet2, phoneNum)
'------------------------------------------------------------------------------------------------------------------------------------
' Construct the parameter string that describes the SetExpressCheckout API call in the shortcut implementation
'------------------------------------------------------------------------------------------------------------------------------------
nvpstr = "&" & Server.URLEncode("PAYMENTREQUEST_0_AMT") & "=" & Server.URLEncode(paymentAmount) & _
"&" & Server.URLEncode("PAYMENTREQUEST_0_PAYMENTACTION")&"=" & Server.URLEncode(paymentType) & _
"&" & Server.URLEncode("RETURNURL") & "=" & Server.URLEncode(returnURL) & _
"&" & Server.URLEncode("CANCELURL") & "=" & Server.URLEncode(cancelURL) & _
"&" & Server.URLEncode("ADDROVERRIDE") & "=1" & _
"&" & Server.URLEncode("PAYMENTREQUEST_0_SHIPTONAME") & "=" & Server.URLEncode(shipToName) & _
"&" & Server.URLEncode("PAYMENTREQUEST_0_SHIPTOSTREET") & "=" & Server.URLEncode(shipToStreet) & _
"&" & Server.URLEncode("PAYMENTREQUEST_0_SHIPTOSTREET2") & "=" & Server.URLEncode(shipToStreet2) & _
"&" & Server.URLEncode("PAYMENTREQUEST_0_SHIPTOCITY") & "=" & Server.URLEncode(shipToCity) & _
"&" & Server.URLEncode("PAYMENTREQUEST_0_SHIPTOSTATE") & "=" & Server.URLEncode(shipToState) & _
"&" & Server.URLEncode("PAYMENTREQUEST_0_SHIPTOCOUNTRYCODE") & "=" & Server.URLEncode(shipToCountryCode) & _
"&" & Server.URLEncode("PAYMENTREQUEST_0_SHIPTOZIP") & "=" & Server.URLEncode(shipToZip) & _
"&" & Server.URLEncode("PAYMENTREQUEST_0_SHIPTOPHONENUM") & "=" & Server.URLEncode(phoneNum) & _
"&"& server.UrlEncode("PAYMENTREQUEST_0_CURRENCYCODE") & "=" & Server.URLEncode(currencyCodeType)
SESSION("currencyCodeType") = currencyCodeType
SESSION("PaymentType") = paymentType
'---------------------------------------------------------------------------
' Make the API call to PayPal to set the Express Checkout token
' If the API call succeded, then redirect the buyer to PayPal to begin to authorize payment.
' If an error occured, show the resulting errors
'---------------------------------------------------------------------------
Set resArray = hash_call("SetExpressCheckout",nvpstr)
ack = UCase(resArray("ACK"))
If ack="SUCCESS" Then
' Save the token parameter in the Session
SESSION("token") = resArray("TOKEN")
End If
set CallMarkExpressCheckout = resArray
End Function
'-------------------------------------------------------------------------------------------------------------------------------------------
' Purpose: Prepares the parameters for the GetExpressCheckoutDetails API and makes the API call.
'
' Inputs:
' token: The token value returned by the SetExpressCheckout call
' Returns:
' The NVP Collection object of the GetExpressCheckoutDetails Call Response.
'--------------------------------------------------------------------------------------------------------------------------------------------
Function GetShippingDetails( token )
'---------------------------------------------------------------------------
' At this point, the buyer has completed authorizing the payment
' at PayPal. The function will call PayPal to obtain the details
' of the authorization, incuding any shipping information of the
' buyer. Remember, the authorization is not a completed transaction
' at this state - the buyer still needs an additional step to finalize
' the transaction
'---------------------------------------------------------------------------
'---------------------------------------------------------------------------
' Build a second API request to PayPal, using the token as the
' ID to get the details on the payment authorization
'---------------------------------------------------------------------------
nvpstr="&TOKEN=" & token
'---------------------------------------------------------------------------
' Make the API call and store the results in an array.
' If the call was a success, show the authorization details, and provide
' an action to complete the payment.
' If failed, show the error
'---------------------------------------------------------------------------
set resArray = hash_call("GetExpressCheckoutDetails",nvpstr)
ack = UCase(resArray("ACK"))
If ack="SUCCESS" Then
' Save the token parameter in the Session
SESSION("PAYERID") = resArray("PAYERID")
End If
set GetShippingDetails = resArray
End Function
'-------------------------------------------------------------------------------------------------------------------------------------------
' Purpose: Prepares the parameters for the GetExpressCheckoutDetails API and makes the call.
'
' Inputs:
' finalPaymentAmount: The final total of the shopping cart including Shipping, Handling and other fees
' Returns:
' The NVP Collection object of the DoExpressCheckoutPayment Call Response.
'--------------------------------------------------------------------------------------------------------------------------------------------
Function ConfirmPayment( finalPaymentAmount )
'------------------------------------------------------------------------------------------------------------------------------------
'---- Use the values stored in the session from the previous SetEC call
'------------------------------------------------------------------------------------------------------------------------------------
token = SESSION("token")
currCodeType = SESSION("currencyCodeType")
paymentType = SESSION("PaymentType")
payerID = SESSION("PayerID")
nvpstr = "&" & Server.URLEncode("TOKEN") & "=" & Server.URLEncode(token) & "&" &_
Server.URLEncode("PAYERID")&"=" &Server.URLEncode(payerID) & "&" &_
Server.URLEncode("PAYMENTREQUEST_0_PAYMENTACTION")&"=" & Server.URLEncode(paymentType) & "&" &_
Server.URLEncode("PAYMENTREQUEST_0_AMT") &"=" & Server.URLEncode(finalPaymentAmount) & "&" &_
Server.URLEncode("PAYMENTREQUEST_0_CURRENCYCODE")& "=" &Server.URLEncode(currCodeType)
'-------------------------------------------------------------------------------------------
' Make the call to PayPal to finalize payment
' If an error occured, show the resulting errors
'-------------------------------------------------------------------------------------------
set ConfirmPayment = hash_call("DoExpressCheckoutPayment",nvpstr)
End Function
'-------------------------------------------------------------------------------------------------------------------------------------------
' Purpose: Prepares the parameters for the DoDirectPayment API and makes the call.
'
' Inputs:
' paymentType: paymentType has to be one of the following values: Sale or Order or Authorization
' paymentAmount: Total value of the shopping cart
' creditCardType Credit card type has to one of the following values: Visa or MasterCard or Discover or Amex or Switch or Solo
' creditCardNumber Credit card number
' expDate Credit expiration date
' cvv2 CVV2
' firstName Customer's First Name
' lastName Customer's Last Name
' street Customer's Street Address
' city Customer's City
' state Customer's State
' zip Customer's Zip
' countryCode Customer's Country represented as a PayPal CountryCode
' currencyCode Customer's Currency represented as a PayPal CurrencyCode
'
' Returns:
' The NVP Collection object of the DoDirectPayment Call Response.
'--------------------------------------------------------------------------------------------------------------------------------------------
Function DirectPayment( paymentType, paymentAmount, creditCardType, creditCardNumber, expDate, cvv2, firstName, lastName, street, city, state, zip, countryCode, currencyCode )
' Construct the parameter string that describes the SetExpressCheckout API call in the shortcut implementation
nvpstr = "&PAYMENTACTION=" & paymentType & _
"&AMT=" & paymentAmount &_
"&CREDITCARDTYPE=" & creditCardType &_
"&ACCT=" & creditCardNumber & _
"&EXPDATE=" & expDate &_
"&CVV2=" & cvv2 &_
"&FIRSTNAME=" & firstName &_
"&LASTNAME=" & lastName &_
"&STREET=" & street &_
"&CITY=" & city &_
"&STATE=" & state &_
"&ZIP=" & zip &_
"&COUNTRYCODE=" & countryCode &_
"&CURRENCYCODE=" & currencyCode
nvpstr = URLEncode(nvpstr)
'-------------------------------------------------------------------------------------------
' Make the call to PayPal to finalize payment
' If an error occured, show the resulting errors
'-------------------------------------------------------------------------------------------
set DirectPayment = hash_call("DoDirectPayment",nvpstr)
End Function
'----------------------------------------------------------------------------------
' Purpose: Make the API call to PayPal, using API signature.
' Inputs:
' Method name to be called & NVP string to be sent with the post method
' Returns:
' NVP Collection object of Call Response.
'----------------------------------------------------------------------------------
Function hash_call ( methodName,nvpStr )
Set objHttp = Server.CreateObject("WinHTTP.WinHTTPRequest.5.1")
nvpStrComplete = "METHOD=" & Server.URLEncode(methodName) & "&VERSION=" & Server.URLEncode(gv_Version) & "&USER=" & Server.URLEncode(gv_APIUserName) & "&PWD=" & Server.URLEncode(gv_APIPassword) & "&SIGNATURE=" & Server.URLEncode(gv_APISignature) & nvpStr
nvpStrComplete = nvpStrComplete & "&BUTTONSOURCE=" & Server.URLEncode( gv_BNCode )
Set SESSION("nvpReqArray")= deformatNVP( nvpStrComplete )
objHttp.open "POST", gv_APIEndpoint, False
WinHttpRequestOption_SslErrorIgnoreFlags=4
objHttp.Option(WinHttpRequestOption_SslErrorIgnoreFlags) = &H3300
If gv_UseProxy Then
'Proxy Call
objHttp.SetProxy gv_Proxy, gv_ProxyServer& ":" &gv_ProxyServerPort
End If
objHttp.Send nvpStrComplete
Set nvpResponseCollection =deformatNVP(objHttp.responseText)
Set hash_call = nvpResponseCollection
Set objHttp = Nothing
If Err.Number <> 0 Then
SESSION("Message") = ErrorFormatter(Err.Description,Err.Number,Err.Source,"hash_call")
SESSION("nvpReqArray") = Null
Else
SESSION("Message") = Null
End If
End Function
'----------------------------------------------------------------------------------
' Purpose: Formats the error Messages.
' Inputs:
'
' Returns:
' Formatted Error string
'----------------------------------------------------------------------------------
Function ErrorFormatter ( errDesc, errNumber, errSource, errlocation )
ErrorFormatter ="<font color=red>" & _
"<TABLE align = left>" &_
"<TR>" &"<u>Error Occured!!!</u>" & "</TR>" &_
"<TR>" &"<TD>Error Description :</TD>" &"<TD>"&errDesc& "</TD>"& "</TR>" &_
"<TR>" &"<TD>Error number :</TD>" &"<TD>"&errNumber& "</TD>"& "</TR>" &_
"<TR>" &"<TD>Error Source :</TD>" &"<TD>"&errSource& "</TD>"& "</TR>" &_
"<TR>" &"<TD>Error Location :</TD>" &"<TD>"&errlocation& "</TD>"& "</TR>" &_
"</TABLE>" &_
"</font>"
End Function
'----------------------------------------------------------------------------------
' Purpose: Convert nvp string to Collection object.
' Inputs:
' NVP string.
' Returns:
' NVP Collection object created from deserializing the NVP string.
'----------------------------------------------------------------------------------
Function deformatNVP ( nvpstr )
On Error Resume Next
Dim AndSplitedArray,EqualtoSplitedArray,Index1,Index2,NextIndex
Set NvpCollection = Server.CreateObject("Scripting.Dictionary")
AndSplitedArray = Split(nvpstr, "&", -1, 1)
NextIndex=0
For Index1 = 0 To UBound(AndSplitedArray)
EqualtoSplitedArray=Split(AndSplitedArray(Index1), "=", -1, 1)
For Index2 = 0 To UBound(EqualtoSplitedArray)
NextIndex=Index2+1
NvpCollection.Add URLDecode(EqualtoSplitedArray(Index2)),URLDecode(EqualtoSplitedArray(NextIndex))
Index2=Index2+1
Next
Next
Set deformatNVP = NvpCollection
If Err.Number <> 0 Then
SESSION("Message") = ErrorFormatter(Err.Description,Err.Number,Err.Source,"deformatNVP")
else
SESSION("Message") = Null
End If
End Function
'----------------------------------------------------------------------------------
' Purpose: URL Encodes a string
' Inputs:
' String to be url encoded.
' Returns:
' Url Encoded string.
'----------------------------------------------------------------------------------
Function URLEncode(str)
On Error Resume Next
Dim AndSplitedArray,EqualtoSplitedArray,Index1,Index2,UrlEncodeString,NvpUrlEncodeString
AndSplitedArray = Split(nvpstr, "&", -1, 1)
UrlEncodeString=""
NvpUrlEncodeString=""
For Index1 = 0 To UBound(AndSplitedArray)
EqualtoSplitedArray=Split(AndSplitedArray(Index1), "=", -1, 1)
For Index2 = 0 To UBound(EqualtoSplitedArray)
If Index2 = 0 then
UrlEncodeString=UrlEncodeString & Server.URLEncode(EqualtoSplitedArray(Index2))
Else
UrlEncodeString=UrlEncodeString &"="& Server.URLEncode(EqualtoSplitedArray(Index2))
End if
Next
If Index1 = 0 then
NvpUrlEncodeString= NvpUrlEncodeString & UrlEncodeString
Else
NvpUrlEncodeString= NvpUrlEncodeString &"&"&UrlEncodeString
End if
UrlEncodeString=""
Next
URLEncode = NvpUrlEncodeString
If Err.Number <> 0 Then
SESSION("Message") = ErrorFormatter(Err.Description,Err.Number,Err.Source,"URLEncode")
else
SESSION("Message") = Null
End If
End Function
'----------------------------------------------------------------------------------
' Purpose: Decodes a URL Encoded string
' Inputs:
' A URL encoded string
' Returns:
' Decoded string.
'----------------------------------------------------------------------------------
Function URLDecode(str)
On Error Resume Next
str = Replace(str, "+", " ")
For i = 1 To Len(str)
sT = Mid(str, i, 1)
If sT = "%" Then
If i+2 < Len(str) Then
sR = sR & _
Chr(CLng("&H" & Mid(str, i+1, 2)))
i = i+2
End If
Else
sR = sR & sT
End If
Next
URLDecode = sR
If Err.Number <> 0 Then
SESSION("Message") = ErrorFormatter(Err.Description,Err.Number,Err.Source,"URLDecode")
else
SESSION("Message") = Null
End If
End Function
'----------------------------------------------------------------------------------
' Purpose: It's Workaround Method for Response.Redirect
' It will redirect the page to the specified url without urlencoding
' Inputs:
' Url to redirect the page
'----------------------------------------------------------------------------------
Function ReDirectURL( token )
On Error Resume Next
payPalURL = PAYPAL_URL & token & "&useraction=commit"
response.clear
response.status="302 Object moved"
response.AddHeader "location", payPalURL
If Err.Number <> 0 Then
SESSION("Message") = ErrorFormatter(Err.Description,Err.Number,Err.Source,"ReDirectURL")
else
SESSION("Message") = Null
End If
End Function
%>
As I have a fully working implementation I am reluctant to embrace a different solution (and go through a whole load more development).
I have a sneaking suspicion that the 'CallShortcutExpressCheckout' is nothing more that a glorified call to SetExpressCheckout with some very specific parameters set and that it need modification or replacing with a direct call to SetExressCheckout?
Has anyone got some sample classic ASP code?
c

Answer 1

I think you can add to the nvpstr more fields.
You can add also a field like "L_PAYMENTREQUEST_0_NUMBER0" to indentify your product/service id/code the user still paying for. (just a suggestion)
I've rebuild one function, but need to be tested if is working right.
Anyway this is an idea:
Function CallShortcutExpressCheckout( title, description, paymentAmount, currencyCodeType, paymentType, returnURL, cancelURL)
'------------------------------------------------------------------------------------------------------------------------------------
' Construct the parameter string that describes the SetExpressCheckout API call in the shortcut implementation
'------------------------------------------------------------------------------------------------------------------------------------
nvpstr = "&" & Server.URLEncode("L_PAYMENTREQUEST_0_NAME0") & "=" & Server.URLEncode(title) & _
"&" & Server.URLEncode("L_PAYMENTREQUEST_0_DESC0") & "=" & Server.URLEncode(description) & _
"&" & Server.URLEncode("PAYMENTREQUEST_0_AMT") & "=" & Server.URLEncode(paymentAmount) & _
"&" & Server.URLEncode("PAYMENTREQUEST_0_PAYMENTACTION")&"=" & Server.URLEncode(paymentType) & _
"&" & Server.URLEncode("RETURNURL") & "=" & Server.URLEncode(returnURL) & _
"&" & Server.URLEncode("CANCELURL") & "=" & Server.URLEncode(cancelURL) & _
"&" & server.UrlEncode("PAYMENTREQUEST_0_CURRENCYCODE") & "=" & Server.URLEncode(currencyCodeType)
SESSION("currencyCodeType") = currencyCodeType
SESSION("PaymentType") = paymentType
'---------------------------------------------------------------------------------------------------------------
' Make the API call to PayPal
' If the API call succeded, then redirect the buyer to PayPal to begin to authorize payment.
' If an error occured, show the resulting errors
'---------------------------------------------------------------------------------------------------------------
Set resArray = hash_call("SetExpressCheckout",nvpstr)
ack = UCase(resArray("ACK"))
If ack="SUCCESS" Then
' Save the token parameter in the Session
SESSION("token") = resArray("TOKEN")
End If
set CallShortcutExpressCheckout = resArray
End Function