The "parallel" flow you have written isn't actually parallel, it's just "independent". Each of the three processors will perform its intended function and pass a flowfile containing *the JSON element it is responsible for* to the destination. Unfortunately, the two components that might seem helpful -- a funnel or MergeContent processor -- do not achieve what you are looking for.
If parallel performance of the three ExecuteStreamCommand processors is really that important, I would recommend using the ExecuteScript processor with a Groovy script that uses an individual thread for each action (either via standard thread management or something like GPars for easy parallel execution). In this case, barring an absolute requirement for "parallel" activity, I would recommend using linear connections between the three ESC processors, and getting the final result of the additive operation into the destination processor. Andy LoPresto [email protected] [email protected] PGP Fingerprint: 70EC B3E5 98A6 5A3F D3C4 BACE 3C6E F65B 2F7D EF69 > On Jun 1, 2016, at 22:25, Kavinaesh Dheenadayalan <[email protected]> wrote: > > Hi Team, > > I am new to nifi and working on a demo to my colleagues. > > I am creating a json by using this flow. The outputs of ExecuteStreamCommand > processor which are json attributes are combined to create a json. > When these three ExecuteStreamCommand processors are connected sequentially > to an AttributesToJSON processor, the flow works fine with all the three > attributes getting populated in the final json. > But when I connect these three ExecuteStreamCommand processors in parallel, > only one random attribute gets populated in the final json. > Please let me know if there is a way to connect these processors in parallel > and get all the attributes in the final json. scheduling or merging or any > other option? > > I have attached the templates, screen shots of the processors for your > reference. > > Wrong output when the flow is parallel: > > { "checks": [ { "Check_Type": "File_Delimiter_Validation", "value": null > }, { "Check_Type": "File_Header_Validation", "value": "0" }, { "Check_Type": > "File_Trailer_Validation", "value": null } ], "fileName": "input.txt" } > > > Correct output when the flow is sequential: > > { "checks": [ { "Check_Type": "File_Delimiter_Validation", "value": "50" > }, { "Check_Type": "File_Header_Validation", "value": "0" }, { "Check_Type": > "File_Trailer_Validation", "value": "100" } ], "fileName": "input.txt" } > > <parallel not working.jpg> > <sequential working.jpg> > <attributesJson.JPG> > <ExecuteStreamCommand.JPG> > <sequential_flow.xml> > <parallel_flow.xml>
