In Post Affiliate Pro (Network) from version 5.0.0.1 and higher  there is a possibility to define a Callback URL that can be executed after each  recorded transaction. In its URL parameters (GET parameters) you can use several variables available from the Insert variable drop-down menu. 
The merchant (network owner) can define the callback URL in the merchant panel at Configuration > Tracking settings > Callback URL
 
 
 
You can choose the desired GET parameters from the Insert variable drop-down menu.