Getting Empty Array Using Groovy Script in Nifi

[#1]

Hi all,

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

Input:

{
"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 org.apache.commons.io.IOUtils
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)
outputStream.write(JsonOutput.prettyPrint(json).getBytes(StandardCharsets.UTF_8))
} 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. 

[#2]

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(data)
println("=" * 80)

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

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

println(jsonOutput.toJson(messages))

This is the output:

[Message:
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"}