From a previous post I made about it:
"We have HTTP endpoints set up to receive data from our ERP's accounting system to send data to Concur and to update customers' Lawson punchout ordering systems with shipment information. The 'E' is an HTTP post with an XML payload. The 'T' consists of using the payload to query other databases to build the 'L' payload, and the 'L' is an HTTP post to the consumer's endpoints."
There's often a misconception about Nifi being batch or file based and not streaming. This probably originates as result of data in Nifi being represented as a FlowFile, which is kind of a misnomer. As woqe stated above, Nifi can certainly doing streaming.
From a previous post I made about it: "We have HTTP endpoints set up to receive data from our ERP's accounting system to send data to Concur and to update customers' Lawson punchout ordering systems with shipment information. The 'E' is an HTTP post with an XML payload. The 'T' consists of using the payload to query other databases to build the 'L' payload, and the 'L' is an HTTP post to the consumer's endpoints."