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Getting Empty Array Using Groovy Script in Nifi


Hi all,


I have an requirement where I need to parse the data into the required format



"Message" : "\nRecord 1:\nRequired data is missing. \n\nRecord 2:\nprocessing failed\n"


Here the content and delimiters are not fixed. The fixed part is only /nRecord keyword on which I am writing the Script. But I am not getting desired Output using Groovy.


desired Output:


"Record 1": "nRequired data is missing"
}, {
"Record 2": "processing failed"


I have written Groovy Script for the same but I am getting empty array.


import groovy.json.*
import java.util.ArrayList
import java.nio.charset.*
import java.nio.charset.StandardCharsets
import groovy.json.JsonSlurper
import groovy.json.JsonBuilder

def flowFile = session.get()
if(!flowFile) return
try {
flowFile = session.write(flowFile,
{ inputStream, outputStream ->
def text = IOUtils.toString(inputStream, StandardCharsets.UTF_8)
splitted = text.split('\nRecord')
int j = splitted.size()
final1 = []
for (int i=0;i<j-1;i++)
k = "Record " + splitted[i+1]
valid = k.replaceAll("\\n|\"|\\n|}","")
final1.add("{\"" + valid.replaceFirst(":",'":"')+ "\"}" )
def json = JsonOutput.toJson(final1)
} as StreamCallback)

session.transfer(flowFile, REL_SUCCESS)
} catch(Exception e) {
log.error('Error during JSON operations', e)
flowFile = session.putAttribute(flowFile, "error", e.getMessage())
session.transfer(flowFile, REL_FAILURE)

Can you please help me with the same.

Thank you. 


Super Collaborator

This is Groovy code that achieves what you've mentioned and should be able to adapt to your scripted processor.

import groovy.json.JsonOutput
import groovy.json.JsonSlurper

JsonSlurper jsonSlurper = new JsonSlurper()
JsonOutput jsonOutput = new JsonOutput()

Map<String, String> data = jsonSlurper.parseText('''{
  "Message": "\nRecord 1:\nRequired data is missing. \n\nRecord 2:\nprocessing failed\n"

println("=" * 80)

List<String> records = data.Message.split("\\nRecord\\s\\d+:\\n").findAll { it.trim() != "" }
println("=" * 80)

Map<String, String> messages = [:]
records.eachWithIndex { message, index ->
    messages["Record ${index + 1}"] = message.trim()


This is the output:

Record 1:
Required data is missing. 

Record 2:
processing failed
[Required data is missing. 
, processing failed
{"Record 1":"Required data is missing.","Record 2":"processing failed"}