def test_price_data_too_old(self):
downloader = SpotPriceDownloader()
open('fake_file.pkl', 'a').close()
oldtime = arrow.utcnow().replace(hours=-5).timestamp
newtime = arrow.utcnow().timestamp
os.utime('fake_file.pkl',(oldtime,oldtime))
self.assertTrue(downloader._price_data_is_old(filename='fake_file.pkl'))
os.utime('fake_file.pkl',(newtime,newtime))
self.assertFalse(downloader._price_data_is_old(filename='fake_file.pkl'))
class SpotPrices:
def __init__(self):
self.log = logging.getLogger(__name__)
self.log.setLevel(logging.INFO)
self.downloader = SpotPriceDownloader()
def datapoint_is_too_old(self,timestamp,start_time):
timestamp = arrow.get(timestamp)
return start_time.replace(minutes=-60) > timestamp
def get_cheapest(self, instance_type='c4.xlarge', region = None, filter_products_by=None):
utcnow = arrow.utcnow()
prices = self.downloader.get_current_prices(instance_type=instance_type)
minimum = {'Timestamp': utcnow, 'AvailabilityZone':'fake-region', 'SpotPrice': 999.00}
for region in prices:
datapoints = region[1]
prices_for_instance_type = [datapoint for datapoint in datapoints if not self.datapoint_is_too_old(datapoint['Timestamp'],utcnow)] or None
if not prices_for_instance_type:
self.log.warning('no prices in {0} for {1}'.format(region[0],instance_type))
continue
if filter_products_by:
latest_price = [price for price in prices_for_instance_type if filter_products_by in price['ProductDescription']][-1]
else:
latest_price = prices_for_instance_type[-1]
if float(latest_price['SpotPrice']) < minimum['SpotPrice']:
minimum = {'Timestamp': latest_price['Timestamp'],
'AvailabilityZone': latest_price['AvailabilityZone'],
'SpotPrice': float(latest_price['SpotPrice']),
'InstanceType': instance_type,
'ProductDescription': latest_price['ProductDescription']}
self.log.info('New minimum at',minimum)
else:
self.log.info('Minimum in {0} was {1}, not beating current best price of {2}'.format(region[0], latest_price['SpotPrice'], arrow.get(latest_price['Timestamp']).humanize(), minimum['SpotPrice']))
return minimum
def pretty_print_price(self, cheapest_object):
print('Cheapest price was {0} for a {1} running {2} in {3}, at {4} ({5})'.format(cheapest_object['SpotPrice'],
cheapest_object['InstanceType'],
cheapest_object['ProductDescription'] ,
cheapest_object['AvailabilityZone'],
arrow.get(cheapest_object['Timestamp']).to('local'),
arrow.get(cheapest_object['Timestamp']).humanize()))
def test_get_prices(self):
downloader = SpotPriceDownloader()
downloader.get_current_prices()
def test_get_regions(self):
downloader = SpotPriceDownloader()
regions = downloader._get_regions()
self.assertTrue(os.path.exists('regions.pkl'))
self.assertIn('us-west-1',regions)
def __init__(self):
self.log = logging.getLogger(__name__)
self.log.setLevel(logging.INFO)
self.downloader = SpotPriceDownloader()
