I need to mark an item as paid for on ebay when a payment is maid through an external payment page (not PayPal). I have been looking at CompleteSale, but this looks like I need a transactionID but how do I get a transactionID of a transaction that hasn't occured on ebay? Maybe im going about this the wrong way.
Anyone know how to mark an item as paid through ebay API? I have the item id, sellers ID and the payer's ebay id.
You're on the right path with CompleteSale but missing some understanding of how it all plugs together.
The transactionID exists as soon as the buyer commits to buy, it is the TransactionID of the sale.
You need to provide the TransactionType.Item.ItemID and the TransactionType.TransactionID, if the sale is an Auction then simply put 0 (Zero) in the field as the ItemID is all that is required to uniquely identify the sale.
You don't need to provide the payer's ID as the transaction can be uniquely identified by the previous fields.
You can get the TransactionID from the eBay API by calling GetSellerTransactionsCall among others.
Hope that helps.