@Heeya8876 , both @SAMSAL and I have recently gone through the adventures of getting 2.0.0-M1 to run with the Python extension enabled.  Here are some findings so far on the Linux side of things. Java 21 is required (any platform) Python 3.9+ (any platform) is required (I believe @SAMSAL, correct me if I'm wrong, said Python 3.12 did NOT work, but we both got 3.11 to run) If it's installed, make sure it's the default set with "sudo update-alternatives java" Make sure your environment has JAVA_HOME defined with the path for Java 21 Make sure Python3.9+ is the default prior to running NiFi with "sudo update-alternatives --config python3" Executing python3 --version should show whichever version you set as your default and it should be 3.9~3.11 You can see what version was copied by NiFi in the directory "./work/python/controller/bin/python3 --version" If this is showing anything <3.9 then delete the work folder, follow the steps above, and try again. If you build a processor from scratch the Developer guide says to use this for your __init__ def __init__(self, **kwargs): super().__init__(**kwargs) You'll get an error...replace super().__init__(**kwargs) with pass like the examples that come with the install. Changes to your Python extensions are not immediate....NiFi polls the directory periodically to detect changes, download dependencies, and load the updated processors. Sometimes I had to restart NiFi to get it to detect my changes if my previous code update made it really unhappy. ./logs/nifi-python.log will be your friend for Python extension related issues If your Python extension has dependencies and it fails to download them you can see the command it attempted in nifi-python.log; I manually ran the commands in the logs and it downloaded the modules into the correct place and worked...perhaps there's a timeout for module downloads? (just a guess since the module had a ton of large dependencies) I don't think I saw it in the Developer's Guide but did notice while building a custom FlowFileTransform Python extension, the "content" data returned with the  FlowFileTransformResult should be a string or byte array. @SAMSAL has additional insight on getting it to start up on Windows ... View more

ExecuteGroovyScript alternative with this input { "idTransakcji": "123", "date": "", "name": "sam" }   import groovy.json.JsonOutput import groovy.json.JsonSlurper import java.nio.charset.StandardCharsets JsonSlurper jsonSlurper = new JsonSlurper() JsonOutput jsonOutput = new JsonOutput() FlowFile flowFile = session.get() if(!flowFile) return flowFile = session.write(flowFile, { inputStream, outputStream -> Map data = jsonSlurper.parse(inputStream) data = [ "id": data.idTransakcji, "user": [ "date": data.date?.isNumber() ? Long.parseLong(data.date) : null, "name": data.name ] ] outputStream.write(jsonOutput.toJson(data).getBytes(StandardCharsets.UTF_8)) } as StreamCallback) session.transfer(flowFile, REL_SUCCESS)   ... View more