Thanks @ashok.kumar . I accepted the @onScheduled answer ... View more

It is synchronous... there is a thread executing the processor's onTrigger command, and a single call to onTrigger should execute your script and write the results to the flow file. ... View more

@Matt Burgess Any insights about how you expect the behavior with "Maximum Timer Driven Thread Count = 1" and two processor with (Max Concurrrent Tasks = 1) ? Any pointers will be greatly appreciated ... View more

Thanks @Shu that was really helpful.. I am just wondering that when I set the number of threads of the whole instance to 1 and I have two processors connected to each other they still manage to somehow run concurrently .. The first processor takes on average 2.5 seconds per input and the second processors takes on average 4.5 seconds.. I gave it 100 inputs and I was expecting it to finish in around 700 seconds (i.e., sequential execution) but it still manages to finish in 480 seconds which suggests that each processor is using a separate thread and they do not wait on each other. Am I missing something here ? ... View more

@Tarek Elgamal The easiest approach to learning the ins and outs of the rest-api is to use the developer tools in your browser to capture the rest-api calls being made as you manually perform similar actions via the NiFi UI. The developer tools in most browsers will even allow to save off those interactions as curl commands. ... View more