Interview Question

code.py

import os
from os.path import join as pj

import functools.partial

import logging
logger = logging.getLogger('my.module')


def getAlerts(ids, default = []):
  """
  Downloads the alerts with `ids`.  If an error is generated then the default is returned
  
  @type  ids: `list` of `number`
  @param ids: List of `Alert` ids to find in the database
  """
  db = getDB()
  try:
    alerts = db.find(Alert.id.in(ids))
  except Exception as ex:
    print ex
    return default
    
  if len(alerts) != len(ids):
    logger.warn('Not all alerts were found')

  return alerts
class Item(object):
  """
  Holds details for an item.

  @type data: object  
  @attr data: Object holding the data blob
  """
  def __init__(self, data):
    self.data = data
    
  def getData(self):
    return self.data
    
  def setData(self, newData):
    self.data = newData
    
    
class Collection(object):
  def __init__(self):
    self._items = []
    
  def add(self, item, logger = None):
    if logger:
      logger.info('Adding: ', item)

    self._items.append(item)
    
  def remove(self, item):
    self._items.remove(item)
    
  def loop(self):
    return iter(self._items)
  

class AlertCollection(Collection):
  def __init__(self):
    Collection.__init__(self)
    
  def loop(self):
    return self._items
    
    
if __name__ == '__main__':
  # Get Alerts from database
  alerts = getAlerts([1, 2, 3, 4])
  
  # Add them to a collection
  collection = AlertCollection()
  adder = functools.partial(collection.add, logger = logger)
  [adder(alert) for alert in alerts]
  
  # Print out the alerts in the collection
  print (alert for alert in collection.loop())