import datetime
import java.io
import json
from java.nio.charset import StandardCharsets
from org.apache.nifi.processor.io import StreamCallback
from org.apache.commons.io import IOUtils


class PyStreamCallback(StreamCallback):
    def __init__(self):
        pass
    def process(self, inputStream, outputStream):
        fcontent = IOUtils.toString(inputStream, StandardCharsets.UTF_8)
        j = json.loads(fcontent)
        t = datetime.datetime.strptime(j['CollectionDate'], '%d.%m.%Y %H:%M:%S').strftime('%Y-%m-%dT%H:%M:%SZ')
        j['MetaInfo'] = [ {'CollectionDate': t }]
        snd = json.dumps(j, sort_keys=True, ensure_ascii=False, indent=4)
        outputStream.write(snd.encode('utf-8'))


flist = session.get(10)
for f in flist:
    try:
        if (f != None):
            f = session.write(f, PyStreamCallback())
            session.transfer(f, REL_SUCCESS)
    except Exception:
        session.transfer(f, REL_FAILURE)