question Re: Start/Stop a NiFi Processor via REST API: Desired State is not set in Support Questions

Start/Stop a NiFi Processor via REST API: Desired State is not set

CommanderLaus — Fri, 21 Jul 2023 13:17:09 GMT

Hi everyone,

I'm trying to use NiFis Rest API to start and stop a Processor, but evertime I get the response

The desired state is not set

Here is my curl-Command which I use:

curl -k --header "Authorization: Bearer $token" -i -H 'Content-Type: application/json' -XPUT -d'{ "revision": { "version": 18, "clientId": "01891026-da00-199f-9dc9-ae3a37dce067" }, "status": { "runStatus": "RUNNING" }, "component": { "id": "0189100e-1e29-115c-ec96-b857cd155f4a", "state": "RUNNING" }, "id": "0189100e-1e29-115c-ec96-b857cd155f4a" }' https://localhost:8443/nifi-api/processors/0189100e-1e29-115c-ec96-b857cd155f4a/run-status

Has anyone an idea what's the problem?

Best regards

Maik

Re: Start/Stop a NiFi Processor via REST API: Desired State is not set

SAMSAL — Fri, 21 Jul 2023 13:28:22 GMT

Hi @CommanderLaus ,

Are you sure that your post data is correct? It needs to be in the following format:

{ "revision": { "clientId": "value", "version": 0, "lastModifier": "value" }, "state": "value", "disconnectedNodeAcknowledged": true }

yours looks like this:

{ "revision": { "version": 18, "clientId": "01891026-da00-199f-9dc9-ae3a37dce067" }, "status": { "runStatus": "RUNNING" }, "component": { "id": "0189100e-1e29-115c-ec96-b857cd155f4a", "state": "RUNNING" }, "id": "0189100e-1e29-115c-ec96-b857cd155f4a" }

refer to : https://nifi.apache.org/docs/nifi-docs/rest-api/index.html

If that helps please accept solution.

Thanks

Re: Start/Stop a NiFi Processor via REST API: Desired State is not set

CommanderLaus — Fri, 21 Jul 2023 13:47:12 GMT

Hi @SAMSAL ,

thank you very much, you where absolutely right. I tried so many solutions from other members from other topics, that I completly messed up my own one.

Nice one, thank's again

Maik

Re: Start/Stop a NiFi Processor via REST API: Desired State is not set

CommanderLaus — Fri, 21 Jul 2023 14:17:53 GMT

Hello again,

if I start the processor via API, the "version" of the processor counts up. In my case above from version 18 to version 19.

If I want to stop the processor now via API, I have to submit the new version 19.

Is it possible to start/stop the processoer without the up-to-date version? Or is it possible, that I get the current version only via API, save it as a variable (e.g. $version) and use this variable in my next API-Call?

Greetings

Maik

Re: Start/Stop a NiFi Processor via REST API: Desired State is not set

SAMSAL — Fri, 21 Jul 2023 14:49:14 GMT

Hi @CommanderLaus ,

If you do anything manually with the processor you are trying to change its Running State through the API, then yes the revision will be updated. In my case what I do is basically the first API InvokeHttp is to get the latest revision using the following GET API:

https://localhost:8443/nifi-api/processors/${pipeline.start.processor.id}

This will give the following response where you can parse the latest "version" value using something like EvaluateJsonPath processor and store the value in an attribute:

{ "revision": { "clientId": "value", "version": 0, "lastModifier": "value" }, "id": "value", "uri": "value", "position": {…}, "permissions": {…}, "bulletins": [{…}], "disconnectedNodeAcknowledged": true, "component": {…}, "inputRequirement": "value", "status": {…}, "operatePermissions": {…} }

Then use extracted version attribute to build the next API post Body , for example in my case I use ReplaceText processor to generate the post body :

{ "revision": { "clientId": "${pipeline.start.processor.id}", "version": ${processorVersion} }, "state": "...", "disconnectedNodeAcknowledged": true }

Hope that helps.