The Data Integration Service generates request messages and interprets response messages based on the method input and output and on the ports that you configure in the REST Web Service Consumer transformation.
Input ports represent different parts of the request message. You can add input ports that identify the resource that you want to retrieve or change. You can also add input ports that represent HTTP headers, cookie information, and elements in the request message.
Output ports represent elements in the response message that you want to send to downstream transformations or to the target in a mapping. You can add output ports that represent HTTP headers, cookie information, the response code, and elements in the response message.