What is the benefit of calling PayPal API SetExpressCheckout method to get a payment link and forwarding a customer there instead of using payment buttons?
The PayPal buttons can be modified by the visitor's browser client. It is just basic HTML. All of the variables to place the order can be manipulated by the customer. For instance, it takes 3 seconds to change the order total from $900 to $1.
Using the API, you tell PayPal to create an incomplete transaction for a certain amount, with certain information, that can then be referenced/completed later and there is no way (short of expert hacking) to change the order. Instead of trusting the visitor's browser, PayPal trusts your server.
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I am making a system in which user permits pre-approval of amount. I've used pre-approval with chained payment. But the problem is that my customer gets redirected to PayPal site and also he/she must have a PayPal account or need to create one. So can i make pre-approval payment using PayPal website payment pro? So my customers will not get redirected to PayPal account. And the process becomes more fast? Note :- I don't want to use authorization and capture method. Thanks.
Edit
One more question :- If i make the website in the UK and the currency in GBP, can I still use the American Paypal account for this?
Auth and Capture is what you're asking for, but then you say you don't want it..?? That's what gives you the functionality you're after, though.
You could do a $0 auth and then run DoReferenceTransaction when you're ready to process the payment as opposed to capturing an actual auth if you want.
Those are your only options when working with Pro, though, and it would give you the same sort of preapproval experience for the buyer.
Here are the steps to accomplish what you're after.
Use DoDirectPayment to run a $0 Authorization (card verification). Users will enter their credit card details directly into a form on your site without any redirection to PayPal (and without any knowledge PayPal is being used at all unless you notify them some way.)
Save the transaction ID that you get form this card verification into your transaction history for the customer in your database. This ID is what will be used to process future payments using that credit card.
When you're ready to process a payment for this customer, pull the ID out of the database and use it with a DoReferenceTransaction request to process any amount you need to.
So the card verification is your preapproval, and then running reference transactions are the same as running Pay requests with a Preapproval key. Both methods accomplish the same thing, but one is with direct credit cards and the other is not.
If you're using PHP you can use this PayPal PHP SDK to make all of the API calls very quick and easy for you. If you're using some other language then there are SDKs available for those as well I'm sure.
Please correct me if i am wrong, #Andrew Angell #Ved Pandya
Auth and Capture or Capture payments later method allows you to do direct payment, but it comes with additional charges, which might not suitable for crowdfunding model as refund/ cancel payment is very frequent
Auth and Capture: You are required to pay $0.30 for each "Card Verification Transactions"
Capture payments later: You are required to pay $0.30 for each "Uncaptured Authorization" that you triggered
https://www.paypal.com/us/webapps/mpp/merchant-fees
I new to paypal integration in asp.net . I found very difficult to understand the paypal api .
I under stood two types -
inline html form ( i.e is also called buy button )
payflow api
my questions are :
which one must be used for recurring payment ( subcription packages for end user)?
in first type , few sites suggested to use IPN for confirmation of payment. I want to know is it neccessary since without using IPN, also using notify_url we can confirm the payment success (as per my knowledge notify_url returns to your site when payment is completed at paypal site)?
for recurring payment , do i need to store user account details (i.e credt card or paypal account ) in my databas?
please do reply with you suggestion .
Thanks
1) You can do it with both, actually. If you want to stick with basic HTML forms then you'd be using Payments Standard, and they call it "Subscriptions". You can easily create a Subscription button from within your PayPal account.
If you're using the API then they call it Recurring Payments (or Recurring Billing). You would use Express Checkout for the PayPal signups, and Payments Pro if you want to handle credit cards directly on your site without any redirect to PayPal.
IPN is useful regardless of what integration method you're using, however, don't get it confused with PDT. PDT sends data back to your site's thank you page, or whatever final page you setup for it, and it only works with Payments Standard. When PDT is configured on Payments Standard, even with Auto-Return enabled, there is no guarantee the user will make it back to your return URL. IPN is very similar, but data will always be POSTed to your IPN listener regardless of whether or not the user makes it back to your site.
You'll also want to use IPN to handle updates for future payments on a subscription / recurring profile. For example, the actual payments, cancelations, suspensions, reactivations, etc.
The notify_url parameter you mentioned is used for IPN. Again, though, this is separate from PDT. A common mistake I've seen many times is when people have their PDT and IPN both set to the same URL. Then when people do make it back to your thank you page, the code actually runs twice. Once from the user actually hitting it, and once again from PayPal's IPN server hitting it. So make sure to avoid that sort of thing.
3) No, you will never save credit card details to your server. The subscription / recurring system handles that using the data that PayPal saves on their servers.
I'm currently trying to implement a mechanism whereby i can return a customer to a success page containing an activated PIN allowing access to a piece of software. The process is a straight forward PIN purchase without any kind of user accounts or login system involved.
I have the payment buttons and IPN script in place and working fine, but this only allows me to email the PIN after a successful payment via the IPN script, since of course the two sessions are completely separate to maintain security.
My problem with this is that i can't be sure the customer has access to the same email they used to pay with via Paypal. I had the idea of asking the user to enter which email they would like the PIN sent to prior to the Paypal redirection and then sending it as a custom value.. but then came visions of a mammoth backlog of support emails where users have entered the wrong email. I would really like to be able to redirect to a success page containing the PIN.
Thanks in advance.
I would recommend using the Express Checkout API. The payer experience is very similar to standard payment buttons, however, the user is always guaranteed to return back to your site, so you can display whatever you want on your final page.
That documentation can be a little scary, but it's really just a matter of utilizing 3 API calls.
SetExpressCheckout - This is used to setup a new transaction and will return a token that you'll append to the end of a redirect URL to PayPal. The user is sent to PayPal, they login and agree to pay, and are then sent back the ReturnURL that you specify in this request.
GetExpressCheckoutDetails - Now back on your site/application, you use this API to obtain information about the buyer like their shipping address, address status, payer status, payer ID, etc. You will need the Payer ID for the final API call.
DoExpressCheckoutPayment - This is very similar to the SetExpressCheckout request, but no transaction is completed until this call is completed. Only then does the money move.
Again, those final calls are done on your site so you can use the API response data to update your database and display details on the final page however you want to.
Keep in mind that payments could still be pending for one reason or another, so you'll want to check the status (returned in the DECP response) and display appropriate information on the final page.
IPN's will still be triggered with Express Checkout so you can adjust the IPN script to handle pending payments or anything else you may want to automate outside the checkout flow.
If you happen to be working with PHP my class library for PayPal will make these calls very quick and easy for you.
This is probably a stupid question, I think I'm having a mental block.
I want to use Paypal's express checkout for buyers to make purchases with as few steps as possible (also using Paypal's optional account feature). The problem is: for me to direct the user to paypal, I will need to have calculated shipping costs, which depends on the country they're in. Obviously I cannot know this unless I have been told one way or another. What are common solutions to this problem?
Ideas:
Use their IP address. Not reliable - various types of proxies, VPNs, anonymizers etc.
Have the user select their country from a drop-down box before I redirect them to paypal
Force them to log in using Paypal's Identity service before calculating postage
Use 1. or 2. and once payment is received, if country is different to expected,
Refund buyer the difference in postage cost or request an additional payment. (Hardly ideal)
Similar to 4., instead of "Sale Payment Action for Express Checkout" Use 1. or 2. in conjunction with one of Paypal's delayed express checkout payment methods and if necessary reduce or increase the amount charged:
Authorization Payment Action for Express Checkout
Order Payment Action for Express Checkout
I'd like to know what solutions other developers have chosen - maybe I've missed an idea. As a consumer, I cannot remember seeing solutions to this.
The general way people do this is simply to use GetExpressCheckoutDetails to obtain the buyer's shipping address, apply any shipping/tax as necessary, and display a final review page on your site that the user would confirm before calling DoExpressCheckoutPayment.
If you want to eliminate the additional review page (PayPal's and then your own) you can use the Instant Update API.
In this case you would include an additional parameter on the URL when you redirect to PayPal (useraction=commit) and this will change the button on the PayPal review page to say Pay instead of Continue.
Also in your SEC request you'll include the CALLBACK parameter and include a URL to your callback listener. PayPal's review page will POST the buyer's shipping address to this callback URL so that you can receive the data, calculate shipping and tax accordingly, and send a response of those options back to the PayPal review page. This will populate the PayPal review page's drop down menu for the shipping option and the user can choose accordingly.
This method allows you to utilize the PayPal review page entirely and finalize the payment there so that the only thing the user sees once they're returned to your site (after you call DECP) is a final thank you / receipt page.
I'm trying to using paypal as payment for my site.
My site only sell a virtual currency, like "Diamond" in Online game.
So after reading i starting to use Express Checkout for Digital Goods, Is that right ? or i must other payment method ?
Then my question is when using Express Checkout for Digital Goods, how to pass custom variable ?
Let say i want to pay user_id, diamond_id, and some other variable from my database to the paypal api. It seem like paypal don't support custom variable to pass on the api call. I want after user complete the payment, then Paypal notify my server that the payment is complete by user_id and some other variable that i pass, so easy for me to know the detail.
after searching i find some solution,
First solution is to store "TOKEN"(Generated from "SetExpressCheckout" Method) and my custom variable which is belong to the TOKEN in the database, Then after payment complete paypal will notify my server the same TOKEN saved before. So i will query based on the TOKEN.
Second Solution is using get style in RETURNURL variable http://www.mysite.com/successpayment.php?user_id=13&diamond_id=88 So i will easy to grab the GET variable.
Which solution is right ? Is there any solution ? and how to secure the payment confirmation, i mean if someone know and hack my returnurl.
Thanks in advance
There are two parts to be able to successfully identify your order in the whole process:
To identify your order when the user is redirected back via the success or cancel URL, just pass the order id via the query string of the URL.
To identify your order when Paypal sends notifications about the transaction and associated events (refunds, reversals, disputes etc.) via IPN: Paypal does support a pass-through variable, which allows you to associate IPNs to the order record in your DB.
For express checkout you set PAYMENTREQUEST_0_INVNUM in the SetExpressCheckout call
In case you are creating a recurring profile, the parameter is named PROFILEREFERENCE in the CreateRecurringPaymentsProfile call
When you receive an IPN the invoice is passed as 'invoice' or 'rp_invoice_id' respectively
(My general advice, though: use Paypal only if you really have to)