heron/shell/src/python/handlers/memoryhistogramhandler.py

#!/usr/bin/env python3
# -*- encoding: utf-8 -*-

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''' memoryhistogramhandler.py '''
import json
import tornado.web

from heron.shell.src.python import utils

class MemoryHistogramHandler(tornado.web.RequestHandler):
  """
  Responsible for getting the memory histogram of a JVM process given its pid.
  """

  # pylint: disable=attribute-defined-outside-init
  @tornado.web.asynchronous
  def get(self, pid):
    ''' get method '''
    body = utils.str_cmd(['jmap', '-histo', pid], None, None)
    self.content_type = 'application/json'
    self.write(json.dumps(body))
    self.finish()