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The setTransaction API call is used to setup/initiate transactions between the merchant and PayU using server to server requests. This has to be done before the customer can pay on the PayU payment page. Minimal detail about the transaction is passes, server-to-server, over HTTP POST or GET requests.
Please note: no special characters are allowed in any of the API call parameters as downstream systems are unable to process them.
After doing a successful setTransaction request, a PayU reference number is issued in response. When the customer's browser redirects to the PayU payment page, this reference number is used to find the correct transaction and effect payment. Append this parameter and its value to the the RPP URL and redirect the customer's browser to the resultant URL e.g.:
https://secure.payu.co.za/rpp.do?PayUReference=123456789
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