Stopping nifi processor without wait/notify processor and curl commands - apache-nifi

Question

I want to terminate invokhttp processor as soon as it fails, for that I use ExecuteStreamCommand processor I have made bat file with code like this:
curl http://localhost:8080/nifi-api/controller/process-groups/root/processors/f511a6a1-015d-1000-970e-969eac1e6fc5'-X PUT -H 'Accept: application/json'-d #stop.json -vv
and I have related json file with code like this:
{
"status": {
"runStatus": "STOPPED"
},
"component": {
"state": "STOPPED",
"id": "f511a6a1-015d-1000-970e-969eac1e6fc5"
},
"id": "f511a6a1-015d-1000-970e-969eac1e6fc5",
"revision": {
"version": 30,
"clientId": "0343f0b9-015e-1000-7cd8-570f8953ec11"
}
}
I use my jso file as an argument for command inside ExecuteStreamCommand processor bat it throws an exception like this:
What should I change?

Answer 1

all actions in nifi that you can do through web browser you can do through nifi-api.
use google chrome you can press F12 to activate DevTools
(other browsers also has this option)
then select Network tab
do required action on nifi (for example stop the processor)
right-click the request and choose menu copy -> copy as cUrl (bash)
now you have curl command in clipboard that repeats the same nifi action through calling nifi-api
you can remove all headers parameters (-H) except one: -H 'Content-Type: application/json'
so the stop action for my processor will look like this:
curl 'http://localhost:8080/nifi-api/processors/d03bbf8b-015d-1000-f7d6-2f949d44cb7f' -X PUT -H 'Content-Type: application/json' --data-binary '{"revision":{"clientId":"09dbb50e-015e-1000-787b-058ed0938d0e","version":1},"component":{"id":"d03bbf8b-015d-1000-f7d6-2f949d44cb7f","state":"STOPPED"}}'
beware! every time you change processor (even state) its version changes.
so before sending stop request you have to get current version & state.
you have to sent GET request to the same url as above without any additional headers:
http://localhost:8080/nifi-api/processors/d03bbf8b-015d-1000-f7d6-2f949d44cb7f
where d03bbf8b-015d-1000-f7d6-2f949d44cb7f is id of your processor.
you can just try this url in browser but replace the processor id in it.
the response will be in json.
{"revision":
{"clientId":"09dbb50e-015e-1000-787b-058ed0938d0e","version":4},
"id":"d03bbf8b-015d-1000-f7d6-2f949d44cb7f",
"uri":
...a lot of information here about this processor...
}
you can take clientId and version from result and use those attributes to build correct STOP request.
PS:
ExecuteStreamCommand transfers flow file into executing command as an input stream that could cause problems
use ExecuteProcess because you passing all the parameters to curl in command line and not through input stream.
you can stop the nifi processor without using curl - you just need to build correct sequence of processors like this:
InvokeHTTP (get current state) -> EvaluateJsonPath (extract version and clientId) -> ReplaceText (build json for stop using attrs from prev step) -> InvokeHTTP (call stop)
try to avoid the logic of stopping processor from nifi - sure it's possible. just re-think your algorithm.

Answer 2

here is template which show how to stop invokehttp processor :
https://www.dropbox.com/s/uv14kuvk2evy9an/StopInvokeHttpPoceesor.xml?dl=0