from __future__ import print_function
import json
import sys
from datetime import datetime
from operator import itemgetter

from pyspark.sql import Row
from pyspark.sql import HiveContext, SQLContext
from pyspark.streaming.kafka import KafkaUtils, OffsetRange
from pyspark.streaming import StreamingContext
from pyspark import SparkConf, SparkContext
from pyspark.storagelevel import StorageLevel


if __name__ == "__main__":
  app_name = "streamingSpark%s" % datetime.today().strftime("%y%m%d_%H%M")
  n_cores = 2
  n_executors = 10
  n_partitions = n_cores * n_executors

  conf = (SparkConf()
    .setAppName(app_name)
    .set("spark.executor.cores" ,"%s" % n_cores)
    )

  sc = SparkContext(conf=conf) # Create new context
  ssc = StreamingContext(sc, 10)

  kafkaParams = {"metadata.broker.list": ...} # 4 brokers
  directKafkaStream = KafkaUtils.createDirectStream(ssc
    , ["Test"]
    , kafkaParams)

  stream_it = (directKafkaStream
    .map(lambda (key, js_string): json.loads(js_string))
    .map(lambda js: js.keys())
    .foreachRDD(lambda rdd: rdd.foreach(lambda x: print(x) ))
    )

  ssc.start()
  ssc.awaitTermination()