Hi,
In NiFi, counters serve monitoring purposes but are not directly accessible
through expression language, and their values are lost upon restart. Instead, I
suggest using an UpdateAttribute processor for this task. Configure it to
'Store State Locally' with an initial value of 0. Add a dynamic attribute,
let's name it 'counter', using the expression
${getStateValue("token"):plus(1)}. This expression appends the incremented
value to every flowfile, increasing it by 1 each time. Next, utilize the
RouteOnAttributeProcessor to route flowfiles based on conditions such as
'${token:equals(n)}'. Finally, use the ReplaceText processor to replace the
flowfile content with the desired text intended for transmission to your
Pub/Sub.
You can find more about trigger-based data processing in NiFi
here<https://medium.com/@rahulsoni4/trigger-based-serial-data-processing-in-nifi-using-wait-and-notify-processor-fa6e0359c6da>.
Best Regards,
Lehel
________________________________
From: [email protected] <[email protected]>
Sent: Wednesday, February 21, 2024 7:59
To: usersnifi.apache.org <[email protected]>
Subject: Track dataflow with counter / updatecounter / statefull
Hello all,
Somebody has already use the Counter or UpdateCounter ?
My use case is sending a message (success) to topic pubsub if my nifi dataflow
has consider to finish.
The input of dataflow is for example 3 flowfiles (do so treatements) and the
ouput will be push to the GCS Bucket.
I want to have a message in the topic pubsub when I'm sure to have thoses 3
files in the bucket.
I'm trying use the updateCounter or statefull with updateAttribute processor
but the "counter" is the owner of the processor so it is a bit difficult to
update this counter.
Have you any information for me about this thing ?
Thanks all
Minh
