examples/src/python/bolt/stream_aggregate_bolt.py

#!/usr/bin/env python
# -*- encoding: utf-8 -*-

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'''stream aggregator'''
from collections import Counter
from heronpy.api.bolt.bolt import Bolt

# pylint: disable=unused-argument
class StreamAggregateBolt(Bolt):
  """Stream counts are aggregated"""
  def initialize(self, config, context):
    self.stream_counter = Counter()

  def process(self, tup):
    self.stream_counter[tup.stream] += 1

  def process_tick(self, tup):
    self.log("Got tick tuple!")
    self.log("Current stream counter: %s" % str(self.stream_counter))