Nifi + Groovy + Apache POI for excel in outputStream

ollie_ — Thu, 29 Sep 2022 12:04:55 GMT

Hi everybody,

i'm new to Nifi, and i try to understand how the in/out streams works in groovy.

I've created one processor to generate flowfile, one to run a groovy script and a third one to putfile.

I've tried many many things but for now my groovy script (not working) look like this:

import org.apache.poi.ss.usermodel.* import org.apache.poi.hssf.usermodel.* import org.apache.poi.xssf.usermodel.* import org.apache.poi.ss.util.* import org.apache.poi.ss.usermodel.* import org.apache.poi.hssf.extractor.* import java.nio.charset.* import java.io.* def flowFile = session.get() if(!flowFile) return flowFile = session.write(flowFile, {inputStream, outputStream -> try { FileOutputStream out = new FileOutputStream("workbook.xls"); outputStream.write(out); out.close(); //is not working. // def record = "toto" // outputStream.write(record.getBytes(StandardCharsets.UTF_8)) //is working and giving me a txt file with toto in it. } catch(e) { log.error("Error during processing", e) session.transfer(flowFile, REL_FAILURE) } } as StreamCallback) session.transfer(flowFile, REL_SUCCESS)

the error i get is :

It says to me that the ProcessSession.write(FlowFile) has not been closed.

When i do outpustream.write of a string, it works, but with a excel file it doesn't work

At this point i really don't know what i'm missing.

My modules are well imported and class path had been setup.

I looked all over the internet but there is no ressource about writing an excel file in the output stream of nifi.

I 'm open to any other way to treat this problem.

Thanks!

Re: Nifi + Groovy + Apache POI for excel in outputStream

yamaga — Wed, 21 Dec 2022 22:35:01 GMT

Hi @ollie_ did you find a solution ?

question Re: Nifi + Groovy + Apache POI for excel in outputStream in Support Questions

Nifi + Groovy + Apache POI for excel in outputStream

Re: Nifi + Groovy + Apache POI for excel in outputStream