Added QPS decorator

This commit is contained in:
Antonio
2017-12-27 14:55:50 +01:00
parent 8c0af7d51d
commit dabd596271
5 changed files with 78 additions and 0 deletions

View File

@@ -7,6 +7,7 @@ import requests
from mapbox import Geocoder
from cartodb_services.metrics import Traceable
from cartodb_services.mapbox.exceptions import ServiceException
from cartodb_services.tools.qps import qps_retry
ACCESS_TOKEN = 'pk.eyJ1IjoiYWNhcmxvbiIsImEiOiJjamJuZjQ1Zjc0Ymt4Mnh0YmFrMmhtYnY4In0.gt9cw0VeKc3rM2mV5pcEmg'
@@ -48,6 +49,7 @@ class MapboxGeocoder(Traceable):
latitude = location[1]
return [longitude, latitude]
@qps_retry(qps=10)
def geocode(self, address, country=None):
response = self._geocoder.forward(address=address,
country=country,

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@@ -7,6 +7,7 @@ from cartodb_services.metrics import Traceable
from cartodb_services.tools.coordinates import (validate_coordinates,
marshall_coordinates)
from exceptions import ServiceException
from cartodb_services.tools.qps import qps_retry
ACCESS_TOKEN = 'pk.eyJ1IjoiYWNhcmxvbiIsImEiOiJjamJuZjQ1Zjc0Ymt4Mnh0YmFrMmhtYnY4In0.gt9cw0VeKc3rM2mV5pcEmg'
@@ -57,6 +58,7 @@ class MapboxMatrixClient(Traceable):
def _parse_matrix_response(self, response):
return response
@qps_retry(qps=1)
def matrix(self, coordinates, profile=DEFAULT_PROFILE):
validate_profile(profile)
validate_coordinates(coordinates,

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@@ -9,6 +9,7 @@ from cartodb_services.tools import PolyLine
from cartodb_services.tools.coordinates import (validate_coordinates,
marshall_coordinates)
from cartodb_services.mapbox.exceptions import ServiceException
from cartodb_services.tools.qps import qps_retry
ACCESS_TOKEN = 'pk.eyJ1IjoiYWNhcmxvbiIsImEiOiJjamJuZjQ1Zjc0Ymt4Mnh0YmFrMmhtYnY4In0.gt9cw0VeKc3rM2mV5pcEmg'
@@ -70,6 +71,7 @@ class MapboxRouting(Traceable):
return MapboxRoutingResponse(geometry, distance, duration)
@qps_retry(qps=1)
def directions(self, waypoints, profile=DEFAULT_PROFILE):
self._validate_profile(profile)
validate_coordinates(waypoints, NUM_WAYPOINTS_MIN, NUM_WAYPOINTS_MAX)

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@@ -0,0 +1,3 @@
class TimeoutException(Exception):
def __str__(self):
return repr('Timeout requesting to mapzen server')

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@@ -0,0 +1,69 @@
import time
import random
from datetime import datetime
from exceptions import TimeoutException
DEFAULT_RETRY_TIMEOUT = 60
DEFAULT_QUERIES_PER_SECOND = 10
def qps_retry(original_function=None,**options):
""" Query Per Second retry decorator
The intention of this decorator is to retry requests against third
party services that has QPS restriction.
Parameters:
- timeout: Maximum number of seconds to retry
- qps: Allowed queries per second. This parameter is used to
calculate the next time to retry the request
"""
if original_function is not None:
def wrapped_function(*args, **kwargs):
if 'timeout' in options:
timeout = options['timeout']
else:
timeout = DEFAULT_RETRY_TIMEOUT
if 'qps' in options:
qps = options['qps']
else:
qps = DEFAULT_QUERIES_PER_SECOND
return QPSService(retry_timeout=timeout, queries_per_second=qps).call(original_function, *args, **kwargs)
return wrapped_function
else:
def partial_wrapper(func):
return qps_retry(func, **options)
return partial_wrapper
class QPSService:
def __init__(self, queries_per_second, retry_timeout):
self._queries_per_second = queries_per_second
self._retry_timeout = retry_timeout
def call(self, fn, *args, **kwargs):
start_time = datetime.now()
attempt_number = 1
while True:
try:
return fn(*args, **kwargs)
except Exception as e:
response = getattr(e, 'response', None)
if response is not None and (response.status_code == 429):
self.retry(start_time, attempt_number)
else:
raise e
attempt_number += 1
def retry(self, first_request_time, retry_count):
elapsed = datetime.now() - first_request_time
if elapsed.total_seconds() > self._retry_timeout:
raise TimeoutException()
# inverse qps * (1.5 ^ i) is an increased sleep time of 1.5x per
# iteration.
delay = (1.0/self._queries_per_second) * 1.5 ** retry_count
# https://www.awsarchitectureblog.com/2015/03/backoff.html
# https://github.com/googlemaps/google-maps-services-python/blob/master/googlemaps/client.py#L193
sleep_time = delay * (random.random() + 0.5)
time.sleep(sleep_time)