title: How to implement the equivalent of the Aggregator EIP in Nifi
body: <p>I'm very experienced with Apache Camel and EIPs and am struggling to understand how to implement equivalents in Nifi. I understand that Nifi uses a different paradigm (flow based programming) but I don't think what I'm trying to do is unreasonable.</p>
  
  <p>In a nutshell I want the contents of each file to be sent to many rest services and I want to aggregate the responses into a single document which will stored in elasticsearch. I might also do some further processing and cleanup to improve what is stored (but this isn't my immediate issue)</p>
  
  <p>The screenshot is a quick mock-up of what I'm trying to achieve but I don't understand enough about Nifi to know how to implement this pattern correctly. </p>
  
  <p><a href="https://i.stack.imgur.com/6JeNq.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/6JeNq.png" alt="Nfii Screenshot"></a></p>